Publications by authors named "Belinda R Beck"

48 Publications

A Comparison of Bone-Targeted Exercise With and Without Antiresorptive Bone Medication to Reduce Indices of Fracture Risk in Postmenopausal Women With Low Bone Mass: The MEDEX-OP Randomized Controlled Trial.

J Bone Miner Res 2021 May 25. Epub 2021 May 25.

Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia.

The goal of the MEDEX-OP trial was to compare the efficacy of a known effective high-intensity resistance and impact training (HiRIT) with a low-intensity exercise control (Buff Bones® [BB]), alone or in combination with antiresorptive bone medication, on indices of fracture risk (bone mass, body composition, muscle strength, functional performance), compliance, and safety. Primary study outcomes were 8-month change in lumbar spine (LS) and total hip (TH) bone mineral density (BMD). Healthy postmenopausal women with low bone mass (T-score ≤ -1.0) on or off stable doses (≥12 months) of antiresorptive medication were recruited. A total of 115 women (aged 63.6 ± 0.7 years; body mass index [BMI] 25.5 kg/m ; femoral neck [FN] T-score -1.8 ± 0.1) were randomly allocated to 8-month, twice-weekly, 40-minute HiRIT (5 sets of 5 repetitions, >80% to 85% 1 repetition maximum) or BB (low-intensity, Pilates-based training), stratified by medication intake, resulting in four groups: HiRIT (n = 42), BB (n = 44), HiRIT-med (n = 15), BB-med (n = 14). HiRIT improved LS BMD (1.9 ± 0.3% versus 0.1 ± 0.4%, p < 0.001) and stature (0.2 ± 0.1 cm versus -0.0 ± 0.1 cm, p = 0.004) more than BB. Both programs improved functional performance, but HiRIT effects were larger for leg and back muscle strength and the five times sit-to-stand test (p < 0.05). There was a positive relationship between maximum weight lifted and changes in LS BMD and muscle strength in the HiRIT groups. Exploratory analyses suggest antiresorptive medication may enhance exercise efficacy at the proximal femur and lumbar spine. Exercise compliance was good (82.4 ± 1.3%) and both programs were well tolerated (7 adverse events: HiRIT 4; BB 3). HiRIT improved indices of fracture risk significantly more than Buff Bones®. More trials combining bone medication and bone-targeted exercise are needed. © 2021 American Society for Bone and Mineral Research (ASBMR).
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http://dx.doi.org/10.1002/jbmr.4334DOI Listing
May 2021

Maternal and Postnatal High Linoleic Acid Diet Impacts Lipid Metabolism in Adult Rat Offspring in a Sex-Specific Manner.

Int J Mol Sci 2021 Mar 14;22(6). Epub 2021 Mar 14.

Institute for Health and Sport, Victoria University, Melbourne, VIC 8001, Australia.

Linoleic acid (LA), an n-6 polyunsaturated fatty acid (PUFA), is essential for fetal growth and development. We aimed to investigate the effect of maternal and postnatal high LA (HLA) diet on plasma FA composition, plasma and hepatic lipids and genes involved in lipid metabolism in the liver of adult offspring. Female rats were fed with low LA (LLA; 1.44% LA) or HLA (6.21% LA) diets for 10 weeks before pregnancy, and during gestation/lactation. Offspring were weaned at postnatal day 25 (PN25), fed either LLA or HLA diets and sacrificed at PN180. Postnatal HLA diet decreased circulating total n-3 PUFA and alpha-linolenic acid (ALA), while increased total n-6 PUFA, LA and arachidonic acid (AA) in both male and female offspring. Maternal HLA diet increased circulating leptin in female offspring, but not in males. Maternal HLA diet decreased circulating adiponectin in males. Postnatal HLA diet significantly decreased aspartate transaminase (AST) in females and downregulated total cholesterol, HDL-cholesterol and triglycerides in the plasma of males. Maternal HLA diet downregulated the hepatic mRNA expression of in both male and female offspring and decreased the hepatic mRNA expression of and in females. Both maternal and postnatal HLA diet decreased hepatic mRNA expression of in females. Postnatal diet significantly altered circulating fatty acid concentrations, with sex-specific differences in genes that control lipid metabolism in the adult offspring following exposure to high LA diet in utero.
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http://dx.doi.org/10.3390/ijms22062946DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7999727PMC
March 2021

Assessment of femoral neck strength and bone mineral density changes following exercise using 3D-DXA images.

J Biomech 2021 04 9;119:110315. Epub 2021 Feb 9.

Medical Device Research Institute, College of Science and Engineering, Flinders University, Adelaide, Australia; School of Mechanical, Medical and Process Engineering, Queensland University of Technology, Brisbane, Australia.

Physical exercise induces spatially heterogeneous bone changes in the proximal femur. Recent advances have enabled 3D dual-energy X-ray Absorptiometry (DXA)-based finite element (FE) models to estimate bone strength. However, its ability to detect exercise-induced BMD and strength changes is unclear. The aim of this study was to quantify the repeatability of vBMD and femoral neck strength obtained from 3D-DXA images and determine the changes due an exercise intervention. The DXA scans included pairs of same-day repeated scans from ten healthy females and pre- and post-exercise intervention scans of 26 males. FE models with element-by-element correspondence were generated by morphing a template mesh to each bone. BMD and femoral strength under single-leg-stance and sideways fall loading configurations were obtained for both groups and compared. In the repeated images, the total hip vBMD difference was 0.5 ± 2.5%. Element-by-element BMD differences reached 30 ± 50%. The strength difference in single-leg stance was 2.8 ± 13% and in sideways fall was 4.5% ± 19%. In the exercise group, strength changes were 6 ± 19% under single-leg stance and 1 ± 18% under sideways fall. vBMD parameters were weakly correlated to strength (R < 0.31). The exercise group had a mean bone accrual exceeding repeatability values in the femoral head and cortical regions. The case with the highest vBMD change (6.4%) caused 18% and -7% strength changes under single-leg stance and sideways fall. 3D-DXA technology can assess the effect of exercise interventions in large cohorts but its validity in individual cases should be interpreted with caution.
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http://dx.doi.org/10.1016/j.jbiomech.2021.110315DOI Listing
April 2021

Comparison of obesity and metabolic syndrome prevalence using fat mass index, body mass index and percentage body fat.

PLoS One 2021 14;16(1):e0245436. Epub 2021 Jan 14.

Betty Byrne Henderson Women's Health Research Centre, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia.

Background: Accurate obesity classification is important so that appropriate intervention can be instituted to modify metabolic risk factors. Commonly utilized body mass index (BMI) and percentage body fat (PBF) are influenced by lean mass whereas fat mass index (FMI) measures only body fat. This study compares the prevalence of obesity and metabolic risk factors with FMI, BMI and PBF using DXA (dual-energy x-ray absorptiometry).

Methods: 489 women randomly recruited from the electoral roll were stratified into 4 age groups; 40-49, 50-59, 60-69 and 70-79 years from 2000 to 2001. Clinical data and DXA body composition were obtained. Statistical analyses were performed using Medcalc v15 (Ostend, Belgium) with significance level at p = 0.05 (two-tailed).

Results: There was higher prevalence of obesity using PBF compared to BMI and FMI (p<0.001). This difference was greater from age 50-59 (p<0.05) which may be explained by age-related lean mass loss. PBF over-classified obesity in over 35% of normal and 95% of overweight categories compared to FMI and BMI. BMI has a sensitivity of 78.9% and specificity of 98.3% for obesity using FMI as the standard. BMI under-classified obesity in the overweight category by 14.9% compared to FMI. There was no difference in diabetes, dyslipidemia, hypertension and metabolic syndrome prevalence within the BMI-obesity and FMI-obesity categories (p>0.05).

Conclusion: PBF classified more obesity than BMI and FMI because of its low pre-determined threshold. The greater difference with PBF compared to BMI and FMI from the 50-59 decade onwards can be attributed to age-related lean mass loss. BMI had the lowest sensitivity for obesity diagnosis. BMI under-classified obesity in the overweight category compared to FMI due to its inability to differentiate lean mass. However, there was no significant difference in the prevalence of metabolic risk factors between BMI and FMI-obesity categories indicating that fat location may influence metabolic dysregulation.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0245436PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7808627PMC
June 2021

The effect of exercise intensity on bone in postmenopausal women (part 2): A meta-analysis.

Bone 2021 02 24;143:115697. Epub 2020 Dec 24.

Menzies Health Institute Queensland, Griffith University, Gold Coast campus, Gold Coast, QLD, Australia; School of Allied Health Sciences, Griffith University, Gold Coast campus, Gold Coast, QLD, Australia; The Bone Clinic, Brisbane, QLD, Australia. Electronic address:

Background: Previous reviews have concluded that exercise has only modest effects on bone mineral density (BMD) in postmenopausal women. Despite the well-recognized strong positive relationship between load magnitude and bone response observed from animal research, the majority of human trials have examined the effects of only low to moderate intensity exercise on bone. We speculated that meta-analysing according to intensity may reveal a more potent exercise effect at higher intensity.

Objectives: To determine the effects of low, moderate and high intensity exercise on BMD at the spine and hip in postmenopausal women.

Methods: Electronic databases and reference lists were searched for RCTs that examined the effect of exercise compared to control on DXA-derived lumbar spine, femoral neck or total hip BMD in healthy postmenopausal women. Interventions were classified as low, moderate or high intensity and pooled based on classification. Mean differences (MD) were calculated using random effects models and a risk of bias analysis was undertaken. To determine the effect of different exercise types (resistance and impact training) on BMD outcomes, subgroup analyses for all intensity categories and outcomes were conducted. Separate meta-analyses were undertaken to examine the influence of adding exercise to a bone medication intervention and to examine exercise effects on fracture risk.

Results: Fifty-three trials, testing 63 interventions (19 low, 40 moderate, 4 high intensity) were included. At the lumbar spine, high intensity exercise yielded greater BMD effects (MD = 0.031 g/cm 95% CI [0.012, 0.049], p = 0.002) than moderate (MD = 0.012 g/cm 95% CI [0.008, 0.017], p < 0.001) and low intensity (MD = 0.010 g/cm 95% CI [0.005, 0.015], p < 0.001). Low and moderate intensity exercise was equally effective at the femoral neck (low: 0.011 g/cm 95% CI [0.006, 0.016], p < 0.001; moderate: 0.011 g/cm 95% CI [0.007, 0.015], p < 0.001), but no effect of high-intensity exercise was observed. Moderate intensity exercise increased total hip BMD (0.008 g/cm 95% CI [0.004, 0.012], p < 0.001), but low intensity did not. There were insufficient data to meta-analyse the effect of high intensity exercise at the total hip. Resistance training, potentially in combination with impact training, appears to be the most effective osteogenic stimulus at the spine and hip. Findings from meta-regression analyses were not informative and no influence of exercise on medication efficacy was observed. Risk of bias was mainly low or unclear due to insufficient information reported.

Conclusion: High intensity exercise is a more effective stimulus for lumbar spine BMD than low or moderate intensity, but not femoral neck BMD, however, the latter finding may be due to lack of power. While data from high-intensity exercise interventions are limited, the current comprehensive meta-analysis demonstrates the same positive relationship between load magnitude and bone response in humans that is observed in animal research. Findings have implications for optimal exercise prescription for osteoporosis in postmenopausal women.

Study Registration: Registered on PROSPERO (CRD42018117254).
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http://dx.doi.org/10.1016/j.bone.2020.115697DOI Listing
February 2021

The effect of exercise intensity on bone in postmenopausal women (part 1): A systematic review.

Bone 2021 02 24;143:115696. Epub 2020 Dec 24.

Menzies Health Institute Queensland, Griffith University, Gold Coast campus, Gold Coast, QLD, Australia; School of Allied Health Sciences, Griffith University, Gold Coast campus, Gold Coast, QLD, Australia; The Bone Clinic, Brisbane, QLD, Australia. Electronic address:

Background: Previous systematic reviews and meta-analyses of exercise effects on bone have reported null or modest effect sizes. While animal research has determined that a strong positive relationship exists between load magnitude/intensity and bone adaptation, nevertheless many human exercise interventions have been applied at low intensity. Meta-analytic pooling of exercise interventions irrespective of intensity dilutes the ability to detect efficacy of any one training regimen. Parsing out efficacy of low, moderate and high intensity exercise interventions will assist the determination of optimal exercise prescription for bone.

Objectives: First, to summarise and critically evaluate existing evidence of exercise effect on bone mass, bone structure and bone turnover markers (BTMs) in healthy postmenopausal women. Second, to examine the influence of intensity on bone response to exercise.

Methods: Electronic databases (Embase, Scopus, CINAHL Plus, SPORTDiscus), database platforms (PubMed, Cochrane CENTRAL, ProQuest Central, Web of Science) and reference lists of included studies were searched for controlled trials and randomised controlled trials that described the effect of any exercise intervention compared to control on bone mass, bone structure or BTMs in healthy postmenopausal women. Fracture incidence was included as an exploratory endpoint. Data was extracted and weighed against the results of a comprehensive risk of bias analysis.

Results: One hundred trials were included, investigating a total of 120 exercise interventions. Of those, 57 interventions were low intensity, 57 were moderate, and six were high intensity. On balance, low intensity exercise was not an effective stimulus to increase bone mass. Higher quality evidence suggests moderate to high intensity interventions, particularly those that combined high intensity resistance and impact training, were most beneficial for bone mass. Only high intensity exercise appears to improve structural parameters of bone strength, however, data are limited. Only low and moderate intensity interventions have measured BTMs and no notable benefits have been observed. The quality of trials varied greatly, and risk of bias determinations were frequently limited by insufficiently reported detail.

Conclusion: Heterogeneity in both study quality and outcomes limits the ability to draw strong conclusions from this comprehensive systematic review of RCT and CT reports. Nevertheless, there is a tendency in the higher quality data to indicate exercise intensity is positively related to the adaptive bone response. Part 2 of this review series reports a meta-analysis of the RCT data in order to draw quantitative conclusions from the higher quality trials.

Study Registration: Registered on PROSPERO (CRD42018117254).
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http://dx.doi.org/10.1016/j.bone.2020.115696DOI Listing
February 2021

Effects of supervised high-intensity resistance and impact training or machine-based isometric training on regional bone geometry and strength in middle-aged and older men with low bone mass: The LIFTMOR-M semi-randomised controlled trial.

Bone 2020 07 11;136:115362. Epub 2020 Apr 11.

Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia; School of Allied Health Sciences, Griffith University, Gold Coast, Queensland, Australia; The Bone Clinic, Brisbane, Queensland, Australia. Electronic address:

Introduction: Few data exist on the effects of bone-targeted exercise on geometric and biomechanical indices of bone strength in men. The Lifting Intervention For Training Muscle and Osteoporosis Rehabilitation for Men (LIFTMOR-M) trial was designed to compare the efficacy and safety of two novel, supervised, twice-weekly, high-intensity exercise programs in middle-aged and older men with osteopenia and osteoporosis on musculoskeletal health and risk factors related to falls and fractures. The current report includes secondary outcomes of the LIFTMOR-M exercise intervention trial.

Purpose: Our goal was to determine the effects of two supervised, twice-weekly, high-intensity exercise programs on bone geometry and strength of the proximal femur, and distal and proximal sites of the tibia and radius in middle-aged and older men with osteopenia and osteoporosis.

Methods: Generally-healthy men (≥45 years), with low lumbar spine (LS) and/or proximal femur areal bone mineral density (aBMD), were recruited from the community. Eligible participants were randomised to either eight months of twice-weekly supervised high-intensity progressive resistance and impact training (HiRIT) or supervised machine-based isometric axial compression (IAC) exercise training. Intervention group outcomes were compared at baseline and eight months with a matched but non-randomised control group (CON) who self-selected to usual activities. DXA scans (Medix DR, Medilink, France) of the skeletally non-dominant proximal femur were analysed using 3D hip software (DMS Group, France) to derive femoral neck (FN) and total hip (TH) bone mineral content (BMC), volume, and volumetric bone mineral density (vBMD) for total, trabecular and cortical bone compartments. Total FN cortical thickness was determined as well as anterior, posterior, lateral and medial subregions. pQCT scans (XCT-3000, Stratec, Germany) of the 4 and 38% sites of the tibia, and 4 and 66% sites of the radius were conducted to determine a range of geometric and bone structural strength indices. Intervention effects were examined using univariate ANCOVA of percent change, and repeated measures ANCOVA of raw baseline and follow-up data, controlling for initial values, using intention-to-treat and per-protocol approaches.

Results: Ninety-three men (67.1 ± 7.5 yrs, 175.2 ± 6.7 cm, 82.1 ± 11.6 kg, 26.7 ± 3.5 kg/m) with lower than average aBMD (LS T-score -0.06 ± 1.04, FN T-score -1.58 ± 0.58, TH T-score -1.00 ± 0.58) were recruited, and designated CON (n = 26) or randomised to HiRIT (n = 34) or IAC (n = 33). Compliance to the supervised exercise programs did not differ (HiRIT 77.8 ± 16.6% versus IAC 78.5 ± 14.8%, p = 0.872). HiRIT improved medial FN cortical thickness compared with CON (5.6 ± 1.7% versus -0.1 ± 1.9%, p = 0.028) and IAC (5.6 ± 1.7% versus 0.7 ± 1.7%, p = 0.044). Distal tibia total BMC, vBMD, area and bone strength index, and trabecular BMC and bone strength index all declined for CON compared with maintenance for both HiRIT and IAC (all p < 0.05). HiRIT maintained distal tibia trabecular area compared with a loss in CON (0.2 ± 0.5% versus -1.6 ± 0.5%, p = 0.013). HiRIT and IAC maintained distal radius total BMC compared with loss in CON (-0.1 ± 0.7% versus -3.7 ± 0.8%, p = 0.001; 1.3 ± 0.7% versus -3.7 ± 0.8%, p < 0.001, respectively). HiRIT and IAC maintained distal radius total bone strength index compared with loss in CON (1.4 ± 1.4% versus -6.0 ± 1.6%, p = 0.001; 0.2 ± 1.3% versus -6.0 ± 1.6%, p = 0.004, respectively). HiRIT reduced proximal radius cortical area compared with CON (-3.1 ± 1.0% versus 1.1 ± 1.2%, p = 0.011) and IAC (-3.1 ± 1.0% versus -0.2 ± 1.0%, p = 0.042). No between-group differences were detected in any pQCT-derived bone outcome at the diaphyseal tibia 38% site.

Conclusion: Findings indicate that supervised HiRIT provides a positive stimulus to cortical bone at the medial FN compared with supervised IAC exercise, and both HiRIT and IAC preserve bone strength at the distal tibia and distal radius. These effects may translate into a reduced risk of lower and upper extremity fracture in middle-aged and older men with low bone mass.
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http://dx.doi.org/10.1016/j.bone.2020.115362DOI Listing
July 2020

A Comparison of Bone-Targeted Exercise Strategies to Reduce Fracture Risk in Middle-Aged and Older Men with Osteopenia and Osteoporosis: LIFTMOR-M Semi-Randomized Controlled Trial.

J Bone Miner Res 2020 08 30;35(8):1404-1414. Epub 2020 Mar 30.

Menzies Health Institute Queensland, Griffith University, Gold Coast, Australia.

The Lifting Intervention For Training Muscle and Osteoporosis Rehabilitation for Men (LIFTMOR-M) trial examined efficacy and safety of two novel exercise programs in older men with low BMD. Men with low hip and/or LS BMD were randomized to high-intensity progressive resistance and impact training (HiRIT) or machine-based isometric axial compression (IAC) and compared to a nonrandomized matched control (CON). Outcomes included: hip and LS BMD; calcaneal ultrasound parameters; anthropometry; body composition; function (timed up-and-go [TUG], five-times sit-to-stand [FTSTS]); back extensor strength (BES); leg extensor strength (LES); compliance and adverse events. Ninety-three men (67.1 ± 7.5 years; 82.1 ± 11.6 kg; 175.2 ± 6.7 cm; FN T-score -1.6 ± 0.6) were randomized to HiRIT (n = 34) or IAC (n = 33), or allocated to CON (n = 26). HiRIT improved trochanteric BMD (2.8 ± 0.8%; -0.1 ± 0.9%, p = .024), LS BMD (4.1 ± 0.7%; 0.9 ± 0.8%, p = .003), BUA (2.2 ± 0.7%; -0.8 ± 0.9%, p = .009), stiffness index (1.6 ± 0.9%; -2.0 ± 1.1%, p = .011), lean mass (1.5 ± 0.8%; -2.4 ± 0.9%, p = .002), TUG, FTSTS, BES, and LES (p < .05) compared with CON. IAC improved lean mass (0.8 ± 0.8%; -2.4 ± 0.9%, p = .013) and FTSTS (-4.5 ± 1.6%; 7.5 ± 2.0%, p < .001) compared with CON. HiRIT improved LS BMD (4.1 ± 0.7%; 2.0 ± 0.7%, p = .039), stiffness index (1.6 ± 0.9%; -1.3 ± 0.9%, p = .025), and FTSTS (-10.7 ± 1.6%; -4.5 ± 1.7%, p = .010) compared with IAC. Exercise compliance was high (HiRIT 77.8 ± 16.6%; IAC 78.5 ± 14.8%, p = .872). There were five minor adverse events (HiRIT, 2; IAC, 3). HiRIT was well-tolerated and improved bone, function and fracture risk more than CON or IAC. © 2020 American Society for Bone and Mineral Research.
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http://dx.doi.org/10.1002/jbmr.4008DOI Listing
August 2020

Characterisation of peripheral bone mineral density in youth at risk of secondary osteoporosis - a preliminary insight.

J Musculoskelet Neuronal Interact 2020 03;20(1):27-52

School of Medical and Health Science, Edith Cowan University, Perth, W.A., Australia.

Objectives: To describe peripheral long bone material and structural differences in youth at risk of secondary osteoporosis across disease-specific profiles.

Methods: Upper- and lower limbs of children and adolescents were scanned at 4% distal and 66% mid-shaft sites using peripheral Quantitative Computed Tomography sub-categorised as (1) increased risk of secondary osteoporosis (neuromuscular disorders; chronic diseases; endocrine diseases; inborn errors of metabolism; iatrogenic conditions), (2) low motor competence and (3) non-affected controls.

Results: Children with disease-specific profiles showed a range of bone deficits compared to the control group with these predominantly indicated for neuromuscular disorders, chronic diseases and low motor competence. Deficits between upper arm and lower leg long bone parameters were different for disease-specific profiles compared to the control group. Endocortical radius, muscle area, and mid-cortical ring density were not significantly different for any disease-specific profile compared to the control group for any bone sites.

Conclusions: Neuromuscular disorders, chronic diseases and low motor competence have a strong correlation to bone health for appendicular bone parameters in youth, suggesting a critical mechanical loading influence which may differ specific to disease profile. As mechanical loading effects are observed in regional bone analyses, targeted exercise interventions to improve bone strength should be implemented to examine if this is effective in reducing the risk of secondary osteoporosis in youth.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7104582PMC
March 2020

Enjoyment and acceptability of different exercise modalities to improve bone health in young adult women.

Health Promot J Austr 2020 Sep 28;31(3):369-380. Epub 2020 Jan 28.

School of Allied Health Sciences, Griffith University, Gold Coast, Queensland, Australia.

Issue Addressed: Osteoporosis presents a serious public health issue and physical activity is recognised as the most effective modifiable risk factor for the condition. The reasons behind physical activity participation, however, are complex. We therefore aimed to explore the experiences related to a bone-targeted exercise intervention, determine enjoyment and acceptability of each exercise mode, and identify barriers and facilitators to osteogenic exercise for young adult women.

Methods: The present study was conducted within the Osteoporosis Prevention Through Impact and Muscle-loading Approaches to Exercise (OPTIMA-Ex) trial, a three-arm RCT comparing musculoskeletal outcomes from two supervised, high-intensity, exercise programs (impact and resistance training) with an unsupervised low-intensity exercise control. A mixed-methods approach was used, including quality of life and physical activity enjoyment questionnaires and qualitative analysis of semi-structured interviews.

Results: All groups had improvements in the 'mental health' domain of the quality of life measure; however, the two supervised exercise groups had greater levels of physical activity enjoyment. The qualitative analysis revealed that overall the trial activities were positively, yet the two supervised groups had 'richer' exercise experiences. Motivations for participation, barriers to physical activity and desired continuation of participation differed between all three groups.

Conclusions: Findings suggest that bone-targeted exercise interventions for young adult women must address perceived time demands and environmental barriers to participation in order to maximise compliance and adherence. SO WHAT?: As physical activity is the most effective lifestyle strategy to improve bone health and young adulthood an important window for its augmentation, increasing convenience, accessibility and understanding of osteoporosis preventative behaviours in this demographic is vital.
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http://dx.doi.org/10.1002/hpja.321DOI Listing
September 2020

A 5-year longitudinal study of changes in body composition in women in the perimenopause and beyond.

Maturitas 2020 Feb 5;132:49-56. Epub 2019 Dec 5.

Betty Byrne Henderson Women's Health Research Centre, Royal Brisbane and Women's Hospital, Butterfield Street, Herston, Queensland 4029, Australia; Faculty of Medicine, University of Queensland, Herston, Queensland 4029, Australia. Electronic address:

Objective: Most studies of the age-related changes in body composition are cross-sectional in design: there have been few longitudinal studies. The aim of this 5-year study was to document body composition changes in perimenopausal and older women.

Study Design: Prospective, longitudinal observational study.

Methods: 489 women were randomly selected from the electoral roll and stratified into 4 age groups by decade: 40-49, 50-59, 60-69 and 70-79 years. Dual-energy x-ray absorptiometry (DXA) was performed in the first and fifth years of the study. Total body mass (TBM), total fat mass (TFM), total lean mass (TLM), abdominopelvic fat mass, and appendicular fat and lean mass were determined.

Results: There were significant increases in TBM (p < 0.001), TFM (p < 0.01), TLM (p < 0.05), arm fat mass (p < 0.05), leg fat mass (p < 0.001) and leg lean mass (p < 0.05) within the 40-49 age decade. TBM, TFM and abdominopelvic fat started to decline from the 50-59 decade. Abdominopelvic fat reduction was significant from the 50-59 decade to the later decades (p = 0.05 to p < 0.001). Arm lean mass showed a significant reduction from the 50-59 decade (p < 0.01). Leg lean mass declined from the 60-69 decade, reaching significance in the 70-79 decade (p = 0.05).

Conclusion: TFM and abdominopelvic fat declined from the 50-59 age decade, which is earlier than is suggested in the literature. Conversely, the decline in appendicular lean mass with age occurred later, from the 50-59 decade, with earlier and greater loss in the arms, which has implications for exercise strategies to maintain muscle mass from midlife on.
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http://dx.doi.org/10.1016/j.maturitas.2019.12.001DOI Listing
February 2020

Regional changes in indices of bone strength of upper and lower limbs in response to high-intensity impact loading or high-intensity resistance training.

Bone 2020 03 15;132:115192. Epub 2019 Dec 15.

Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia; School of Allied Health Sciences, Griffith University, Gold Coast, Queensland, Australia. Electronic address:

It is well known that the bone response to physical activity is highly dependent on the nature of the loads imposed. Despite this, few direct comparisons of the effect of impact-style loading and resistance training on bone have been made. We therefore aimed to compare the effects of 10-month, twice-weekly, high-impact loading and 10-month, twice-weekly, high-intensity resistance training on indices of bone strength of both the upper and lower limbs of young adult women. Physically inactive, otherwise healthy, young adult women (18-30 years) with below average bone mass (T-score ≤ 0) were recruited as part of the OPTIMA-Ex trial. Testing included DXA- and pQCT-derived measures of bone mass and indices of bone strength and QUS-derived measures of bone quality of the dominant (D) and non-dominant (ND) upper (radius) and lower limbs (femoral neck, tibia, calcaneus). The present study examined those participants who completed the impact training (IT; n = 10) and resistance training (RT; n = 12) arms of the trial. Age differed between groups at baseline (IT = 23.2 ± 3.8 years, RT = 20.5 ± 1.8 years; p = 0.042). Compliance with the training programs did not differ (IT = 61.4 ± 15.1%, RT = 66.4 ± 11.2%, p = 0.381). Age and baseline differences in bone outcomes served as covariates for repeated measures and univariate ANCOVA conducted for dependent variables and percent change respectively. IT improved distal pQCT-derived bone mineral density (BMD) of the upper limb (ND radius: total BMD = 8.55 ± 2.26% versus 1.50 ± 2.04%, p = 0.040 and trabecular BMD = 1.86 ± 0.90% versus -1.30 ± 0.81%, p = 0.029) and lower limb (ND tibia trabecular BMD = 1.22 ± 0.55% versus -0.82 ± 0.50%, p = 0.017), more than RT. IT also improved upper limb bone strength index (BSI) (ND radius total BSI = 15.35 ± 2.83% versus 2.67 ± 2.55, p = 0.005) and lower limb BSI (D tibia total BSI = 5.16 ± 1.13% versus 0.37 ± 1.02%, p = 0.008; D tibia trabecular BSI = 3.93 ± 1.76% versus -2.84 ± 1.59, p = 0.014, ND tibia trabecular BSI = 3.57 ± 1.63% versus -3.15 ± 1.48%, p = 0.009) more than RT. Conversely, RT improved DXA-derived cortical volumetric BMD at the femoral neck more than IT (3.68 ± 1.99% versus -4.14 ± 2.20%, p = 0.021). Results suggest that IT and RT provide differing site-specific effects in both the upper and lower limbs, with superior bone responses observed at the distal segment from IT, while RT appeared to have greater effect on the shaft of the bone, on indices of bone-strength in young adult women.
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http://dx.doi.org/10.1016/j.bone.2019.115192DOI Listing
March 2020

Bone health of middle-aged and older surfers.

Open Access J Sports Med 2019 6;10:123-132. Epub 2019 Sep 6.

Water Based Research Unit, Bond Institute of Health and Sport, Faculty of Health Sciences and Medicine, Bond University, Gold Coast, QLD, Australia.

Purpose: Given the lack of research investigating surfing and bone health, we aimed to assess the bone mineral density (BMD) of middle-aged and older surfers.

Patients And Methods: In a cross-sectional observational design, we compared a group of middle-aged and older surfers to a group of non-surfers, age- and sex-matched controls. Participants were males, aged between 50 and 75 years. Volunteers were assessed for body mass index, bone-specific physical activity questionnaire (BPAQ) scores, daily calcium intake, and alcohol intake. Primary outcomes included BMD at the femur and lumbar spine (LS), and T-score, assessed via dual-energy X-ray absorptiometry. Bone biomarkers were also analyzed.

Results: A total of 104 participants (59 surfers and 45 controls) were assessed. Groups were similar with regards to all demographic characteristics except for percentage of lean mass (higher in surfers, mean difference [MD] +2.57%; 95% CI 0.05-5.09; =0.046) and current BPAQ score (lower in surfers; MD -0.967; 95% CI -0.395 to -1.539; =0.001). Surfers had a mean surfing experience of 41.2 (SD ±11.8) years and mean surfing exposure of 26.9 (SD ±15.0) hours/month. Controls were divided into two groups, according to their main physical activity: weight-bearing/high intensity (WBHI) and non-weight-bearing/low intensity (NWBLI). When compared to NWBLI controls, surfers had higher LS BMD (MD +0.064; 95% CI 0.002-0.126; =0.041) and higher T-score (MD +0.40; 95% CI 0.01-0.80; =0.042); however, surfers had a lower T-score than the WBHI group (MD -0.52; 95% CI -0.02 to -1.0; =0.039). No other differences were found between groups.

Conclusion: The findings of this study support our hypothesis that regular surfing may be an effective physical activity for middle-aged and older men to decrease bone deterioration related to aging, as we identified positive results for surfers in relation to primary outcomes.
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http://dx.doi.org/10.2147/OAJSM.S209043DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6735650PMC
September 2019

The influence of antiresorptive bone medication on the effect of high-intensity resistance and impact training on osteoporotic fracture risk in postmenopausal women with low bone mass: protocol for the MEDEX-OP randomised controlled trial.

BMJ Open 2019 09 5;9(9):e029895. Epub 2019 Sep 5.

Menzies Health Institute Queensland and School of Allied Health Sciences, Griffith University, Gold Coast, Queensland, Australia

Introduction: Antiresorptive medications increase bone density and decrease vertebral fracture, while high-intensity resistance and impact training (HiRIT) increases balance, bone and muscle strength decreasing risk for falls and fractures. Medications are typically prescribed by doctors and exercise by exercise specialists, frequently in isolation.

Objective: Our primary aim is to determine the effect of an 8-month HiRIT programme with or without osteoporosis medications on bone mineral density (BMD) of the spine and hip in postmenopausal women with low bone mass.

Methods And Analysis: One hundred and sixty postmenopausal women with low bone mass will be recruited from the community to participate in an 8-month randomised controlled trial. Participants will be on stable doses of antiresorptive bone medication for at least 12 months (n=80) or have not taken bone medications for at least 12 months (n=80). Participants will be block randomised, stratified by medication intake, to twice-weekly 40-min supervised sessions of HiRIT or a low-intensity exercise programme (control). Primary outcomes include change in lumbar spine and total hip areal bone mineral density. Secondary outcomes include whole body, femoral neck and forearm BMD, proximal femur bone geometry and volumetric density, vertebral morphology, body composition, anthropometry, physical function, posture, rate of falls, osteoarthritis symptoms, pelvic floor health, quality of life, physical activity enjoyment, resting blood pressure, safety and compliance. All outcomes will be assessed at baseline and 8 months and intention-to-treat and per-protocol analyses will be conducted. Repeated measure analysis of covariance will be used to determine intervention effects on outcome measures, controlling for initial values, compliance and other variables found to differ between groups at baseline.

Ethics And Dissemination: The study has been approved by Griffith University Human Research Ethics Committee (Ref: 2017/739). Results will be reported in peer-reviewed journals and at conferences.

Trial Registration Number: Australian New Zealand Clinical Trials Registry (ACTRN12617001511325).
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http://dx.doi.org/10.1136/bmjopen-2019-029895DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6731910PMC
September 2019

Landing Impact Intensities for Jumping Exercises From the OPTIMA-Ex Trial in Trained and Untrained Women.

J Strength Cond Res 2019 Aug 8. Epub 2019 Aug 8.

Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia.

Lambert, C, Beck, BR, and Weeks, BK. Landing impact intensities for jumping exercises from the OPTIMA-Ex trial in trained and untrained women. J Strength Cond Res XX(X): 000-000, 2019-High-intensity mechanical loads are required to elicit a positive adaptive bone response. Our aim was to quantify the mechanical loads of impact exercises used in each progressive stage of a bone-targeted exercise intervention (the OPTIMA-Ex trial) and to investigate differences in mechanical loads between untrained and trained subjects. A randomized repeated measures experimental design was used to quantify and compare the mechanical loads, including vertical ground reaction force (vGRF) and the rate of loading (RoL) of the landing phase, of all impact exercises applied in the OPTIMA-Ex trial and to determine the load intensity for each training stage of the impact intervention. Fifteen healthy young adult women aged 18-30 years (mean 23.1 ± 3.5 years) were recruited (5 trained and 10 untrained). Overall, vGRF was classified as high impact (>4 times body mass [BM]) for all 7 training stages (4.70 ± 1.89 to 6.79 ± 2.17 BM), whereas RoL ranged from 207.01 ± 175.09 to 371.52 ± 393.43 BM·s across the stages. Furthermore, a significant time effect was observed between training stages for vGRF/BM (p = 0.001) and RoL (p < 0.001). Trained subjects exhibited greater impact loads than untrained subjects for activities at every training stage (p < 0.01). We found that impact activities at every stage of the OPTIMA-Ex trial not only met the GRF criteria for high intensity but also exhibited progressive increases in load for successive stages. Furthermore, trained subjects were capable of producing greater impact loads than untrained subjects.
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http://dx.doi.org/10.1519/JSC.0000000000003204DOI Listing
August 2019

Cancellous bone and theropod dinosaur locomotion. Part I-an examination of cancellous bone architecture in the hindlimb bones of theropods.

PeerJ 2018 31;6:e5778. Epub 2018 Oct 31.

School of Allied Health Sciences, Griffith University, Gold Coast, QLD, Australia.

This paper is the first of a three-part series that investigates the architecture of cancellous ('spongy') bone in the main hindlimb bones of theropod dinosaurs, and uses cancellous bone architectural patterns to infer locomotor biomechanics in extinct non-avian species. Cancellous bone is widely known to be highly sensitive to its mechanical environment, and has previously been used to infer locomotor biomechanics in extinct tetrapod vertebrates, especially primates. Despite great promise, cancellous bone architecture has remained little utilized for investigating locomotion in many other extinct vertebrate groups, such as dinosaurs. Documentation and quantification of architectural patterns across a whole bone, and across multiple bones, can provide much information on cancellous bone architectural patterns and variation across species. Additionally, this also lends itself to analysis of the musculoskeletal biomechanical factors involved in a direct, mechanistic fashion. On this premise, computed tomographic and image analysis techniques were used to describe and analyse the three-dimensional architecture of cancellous bone in the main hindlimb bones of theropod dinosaurs for the first time. A comprehensive survey across many extant and extinct species is produced, identifying several patterns of similarity and contrast between groups. For instance, more stemward non-avian theropods (e.g. ceratosaurs and tyrannosaurids) exhibit cancellous bone architectures more comparable to that present in humans, whereas species more closely related to birds (e.g. paravians) exhibit architectural patterns bearing greater similarity to those of extant birds. Many of the observed patterns may be linked to particular aspects of locomotor biomechanics, such as the degree of hip or knee flexion during stance and gait. A further important observation is the abundance of markedly oblique trabeculae in the diaphyses of the femur and tibia of birds, which in large species produces spiralling patterns along the endosteal surface. Not only do these observations provide new insight into theropod anatomy and behaviour, they also provide the foundation for mechanistic testing of locomotor hypotheses via musculoskeletal biomechanical modelling.
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http://dx.doi.org/10.7717/peerj.5778DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6215452PMC
October 2018

Exercise, Osteoporosis, and Bone Geometry.

Sports (Basel) 2017 May 12;5(2). Epub 2017 May 12.

Menzies Health Institute Queensland, Griffith University, Gold Coast campus, Gold Coast 4222, Australia.

Exercise is commonly recommended in the prevention and management of osteoporosis. The most common method to monitor bone mass and its response to interventions is bone densitometry. While closely associated with risk of fracture, densitometry-derived areal bone mineral density (aBMD) does not provide a reliable indication of bone geometry or morphological adaptation to stimuli. In fact, the effects of exercise interventions on aBMD are frequently modest, and may not fully represent the benefit of exercise to bone. Animal models suggest that mechanical loading indeed influences bone geometry and thus strength. Such an effect in humans has the potential to reduce osteoporotic fracture. The aim of the current narrative review is to provide an overview of what is known about the effects of exercise on bone geometry, with a focus on relevance to osteoporosis.
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http://dx.doi.org/10.3390/sports5020029DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5968984PMC
May 2017

Concurrent Validity and Reliability of a Linear Positional Transducer and an Accelerometer to Measure Punch Characteristics.

J Strength Cond Res 2018 Mar;32(3):675-680

School of Allied Health Sciences and Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia.

Lambert, C, Beck, BR, and Weeks, BK. Concurrent validity and reliability of a linear positional transducer and an accelerometer to measure punch characteristics. J Strength Cond Res 32(3): 675-680, 2018-Punch speed is an important factor in the sport of boxing, and its measurement has important implications for monitoring training progression and outcomes. The aim of the current study was to establish the concurrent validity and reliability of a linear positional transducer and an accelerometer for the quantification of punch characteristics in untrained adults. Men and women aged 18-30 years with no previous boxing experience and no upper-limb musculoskeletal injuries were recruited. Participants performed 6 straight right punches; 3 at a self-determined 50% effort; and 3 at maximum effort. An accelerometer (Crossbow) and a linear positional transducer (GymAware) were used to examine peak velocity and acceleration of each punch. Validity was examined using Pearson's correlation analyses and by calculating mean bias and limits of agreement between measures from each device, whereas reliability was established using intraclass correlation coefficients (ICCs). Forty-four healthy young adults (28M and 16F; age 22.2 ± 2.9 years) participated. Moderate-to-strong positive associations were observed for both devices at 50% effort for velocity (r = 0.572-0.696) and acceleration (r = 0.867-0.921) and at maximum effort for velocity (r = 0.748-0.781) and acceleration (r = 0.897-0.946). High levels of reliability were observed with maximum punches for both devices (ICC = 0.922-0.981). Overall, moderate-strong measurement validity and reliability for punch speed was observed between the accelerometer and GymAware. Thus, the GymAware linear positional transducer is an acceptable measurement tool for the quantification of punch speed for straight punches in untrained adults.
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http://dx.doi.org/10.1519/JSC.0000000000002284DOI Listing
March 2018

High-Intensity Resistance and Impact Training Improves Bone Mineral Density and Physical Function in Postmenopausal Women With Osteopenia and Osteoporosis: The LIFTMOR Randomized Controlled Trial.

J Bone Miner Res 2018 02 4;33(2):211-220. Epub 2017 Oct 4.

School of Allied Health Sciences, Griffith University, Gold Coast, Queensland, Australia.

Optimal osteogenic mechanical loading requires the application of high-magnitude strains at high rates. High-intensity resistance and impact training (HiRIT) applies such loads but is not traditionally recommended for individuals with osteoporosis because of a perceived high risk of fracture. The purpose of the LIFTMOR trial was to determine the efficacy and to monitor adverse events of HiRIT to reduce parameters of risk for fracture in postmenopausal women with low bone mass. Postmenopausal women with low bone mass (T-score < -1.0, screened for conditions and medications that influence bone and physical function) were recruited and randomized to either 8 months of twice-weekly, 30-minute, supervised HiRIT (5 sets of 5 repetitions, >85% 1 repetition maximum) or a home-based, low-intensity exercise program (CON). Pre- and post-intervention testing included lumbar spine and proximal femur bone mineral density (BMD) and measures of functional performance (timed up-and-go, functional reach, 5 times sit-to-stand, back and leg strength). A total of 101 women (aged 65 ± 5 years, 161.8 ± 5.9 cm, 63.1 ± 10.4 kg) participated in the trial. HiRIT (n = 49) effects were superior to CON (n = 52) for lumbar spine (LS) BMD (2.9 ± 2.8% versus -1.2 ± 2.8%, p < 0.001), femoral neck (FN) BMD (0.3 ± 2.6% versus -1.9 ± 2.6%, p = 0.004), FN cortical thickness (13.6 ± 16.6% versus 6.3 ± 16.6%, p = 0.014), height (0.2 ± 0.5 cm versus -0.2 ± 0.5 cm, p = 0.004), and all functional performance measures (p < 0.001). Compliance was high (HiRIT 92 ± 11%; CON 85 ± 24%) in both groups, with only one adverse event reported (HiRIT: minor lower back spasm, 2/70 missed training sessions). Our novel, brief HiRIT program enhances indices of bone strength and functional performance in postmenopausal women with low bone mass. Contrary to current opinion, HiRIT was efficacious and induced no adverse events under highly supervised conditions for our sample of otherwise healthy postmenopausal women with low to very low bone mass. © 2017 American Society for Bone and Mineral Research.
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http://dx.doi.org/10.1002/jbmr.3284DOI Listing
February 2018

A protocol for a randomised controlled trial of the bone response to impact loading or resistance training in young women with lower than average bone mass: the OPTIMA-Ex trial.

BMJ Open 2017 Sep 1;7(9):e016983. Epub 2017 Sep 1.

Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia.

Introduction: The aim of the Osteoporosis Prevention Through Impact and Muscle-loading Approaches to Exercise trial is to compare the bone response to two known osteogenic stimuli - impact loading exercise and resistance training. Specifically, we will examine the effect of a 10-month, twice-weekly, high-intensity impact loading exercise intervention and a 10-month, twice-weekly, high-intensity resistance training intervention on bone mass and strength at clinically important skeletal sites. The intervention groups will be compared against a home-based 'positive' control group. Safety and acceptability of each exercise modality will also be determined.

Methods And Analysis: Sedentary otherwise healthy young women aged 18-30 years with bone mineral density (BMD) T-scores less than or equal to 0 at the hip and lumbar spine, screened for conditions and medications that influence bone and physical function, will be recruited. Eligible participants are randomised to 10-month, twice-weekly, either supervised high-intensity impact training, high-intensity resistance training or a home-based 'positive' control group. The primary outcome measure will be lumbar spine areal BMD, while secondary outcome measures will include: whole body, femoral neck and regional measures (upper and lower limb) of bone, muscle and fat; anthropometrics; muscle strength and power; quality of life and exercise safety, enjoyment and acceptability. All outcome measures will be conducted at baseline (T0) and 10 months (T10) and will be analysed according to the intention-to-treat principle and per protocol.

Ethics And Dissemination: The study has been granted ethical approval from the Griffith University Human Research Ethics Committee (GU Ref: 2015/775). Standard scientific reporting practices will occur, including publication in peer-reviewed journals. Participant confidentiality will be maintained in all forms of reporting.

Trial Registration Number: ACTRN12616001444471.
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http://dx.doi.org/10.1136/bmjopen-2017-016983DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5588984PMC
September 2017

Please Don't Move-Evaluating Motion Artifact From Peripheral Quantitative Computed Tomography Scans Using Textural Features.

J Clin Densitom 2018 Apr - Jun;21(2):260-268. Epub 2017 Aug 8.

Western Australian Bone Research Collaboration, Perth, WA, Australia; School of Health Sciences, The University of Notre Dame Australia, Fremantle, WA, Australia; Department of Endocrinology, Princess Margaret Hospital, Perth, WA, Australia; School of Paediatrics and Child Health, University of Western Australia, Nedlands, WA, Australia.

Most imaging methods, including peripheral quantitative computed tomography (pQCT), are susceptible to motion artifacts particularly in fidgety pediatric populations. Methods currently used to address motion artifact include manual screening (visual inspection) and objective assessments of the scans. However, previously reported objective methods either cannot be applied on the reconstructed image or have not been tested for distal bone sites. Therefore, the purpose of the present study was to develop and validate motion artifact classifiers to quantify motion artifact in pQCT scans. Whether textural features could provide adequate motion artifact classification performance in 2 adolescent datasets with pQCT scans from tibial and radial diaphyses and epiphyses was tested. The first dataset was split into training (66% of sample) and validation (33% of sample) datasets. Visual classification was used as the ground truth. Moderate to substantial classification performance (J48 classifier, kappa coefficients from 0.57 to 0.80) was observed in the validation dataset with the novel texture-based classifier. In applying the same classifier to the second cross-sectional dataset, a slight-to-fair (κ = 0.01-0.39) classification performance was observed. Overall, this novel textural analysis-based classifier provided a moderate-to-substantial classification of motion artifact when the classifier was specifically trained for the measurement device and population. Classification based on textural features may be used to prescreen obviously acceptable and unacceptable scans, with a subsequent human-operated visual classification of any remaining scans.
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http://dx.doi.org/10.1016/j.jocd.2017.07.002DOI Listing
November 2019

The LIFTMOR-M (Lifting Intervention For Training Muscle and Osteoporosis Rehabilitation for Men) trial: protocol for a semirandomised controlled trial of supervised targeted exercise to reduce risk of osteoporotic fracture in older men with low bone mass.

BMJ Open 2017 06 12;7(6):e014951. Epub 2017 Jun 12.

Menzies Health Institute Queensland, Griffith University, Gold Coast Campus, Gold Coast, Queensland, Australia.

Introduction: The primary aim of the proposed study is to examine the efficacy of an 8-month supervised, high-intensity progressive resistance training and impact loading programme in comparison with a supervised machine-based isometric exercise training programme using the bioDensity system in older men with low bone mass. We will also determine the safety and acceptability of each exercise training mode. Intervention group responses will be compared with those of a self-selected, non-randomised control sample of sex-matched and age-matched men who will follow their usual lifestyle activities for 8 months.

Methods And Analysis: Apparently healthy men over 50 years with low bone mass, screened for medical conditions and medications known to adversely affect bone health, will be recruited. Eligible participants will be randomly allocated to 8 months of either exercise programme with block randomisation based on presence or absence of osteoporosis medications. A twice-weekly, 30-minute, supervised exercise programme will be conducted for both groups. The primary outcome will be change in femoral neck areal bone mineral density determined by dual-energy X-ray absorptiometry (DXA). Secondary outcomes, assessed at baseline and 8 months, will include: DXA-derived whole-body, bilateral proximal femur and lumbar spine areal bone mineral density; proximal femur bone geometry and volumetric density extracted using three-dimensional hip analysis software; anthropometry; body composition; kyphosis; vertebral fracture assessment; physical function; safety (adverse events and injuries); and compliance. Intention-to-treat and per-protocol analyses will be conducted.

Discussion: Whether a high-intensity, low-repetition progressive resistance training and impact loading programme or a machine-based isometric exercise programme can improve determinants of fracture risk, without causing injury, has not been examined in men. Determination of the efficacy, safety and acceptability of such programmes will facilitate formulation of future exercise guidelines for older men with low bone mass at risk of fragility fracture, a group who have previously been under-represented.

Ethics And Dissemination: Participant confidentiality will be maintained with publication of results. The study has been granted ethical approval from the Griffith University Human Research Ethics Committee (Protocol number AHS/07/14/HREC).

Trial Registration Number: Australian New Zealand Clinical Trials Registry (www.anzctr.org.au)ANZCTR12616000344493; Pre-results.
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http://dx.doi.org/10.1136/bmjopen-2016-014951DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5541517PMC
June 2017

Exercise for Bone in Childhood-Hitting the Sweet Spot.

Authors:
Belinda R Beck

Pediatr Exerc Sci 2017 11 11;29(4):440-449. Epub 2017 Oct 11.

1 Griffith University.

Purpose: The goal of the current work is to challenge the enduring notion that prepuberty is the optimum timing for maximum bone response to exercise in childhood and to present the evidence that early puberty is a more potently receptive period.

Method: The relevant literature is reviewed and the causes of the misconception are addressed in detail.

Results: Contrary to prevailing opinion, ample evidence exists to suggest that the peripubertal years represent the developmental period during which bone is likely to respond most robustly to exercise intervention.

Conclusion: Public health initiatives that target bone-specific exercise interventions during the pubertal years are likely to be the most effective strategy to harness the increased receptiveness of the growing skeleton to mechanical loading.
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http://dx.doi.org/10.1123/pes.2017-0023DOI Listing
November 2017

Feasibility of using MRIs to create subject-specific parallel-mechanism joint models.

J Biomech 2017 02 29;53:45-55. Epub 2016 Dec 29.

Menzies Health Institute Queensland, Griffith University, Australia.

Musculoskeletal models typically use generic 2D models for the tibiofemoral (TFJ) and patellofemoral (PFJ) joints, with a hinge talocrural joint (TCJ), which are scaled to each subject׳s bone dimensions. Alternatively joints' measured kinematics in cadavers are well-predicted using 3D cadaver-specific models. These employ mechanisms constrained by the articulations of geometric objects fitted to the joint׳s surfaces. In this study, we developed TFJ, PFJ and TCJ mechanism-based models off MRIs for fourteen participants and compared the estimated kinematics with those from published studies modified to be consistent with mechanisms models and subject-specific anatomical landmarks. The models' parameters were estimated by fitting spheres to segmented articular cartilage surfaces, while ligament attachment points were selected from their bony attachment regions. Each participant׳s kinematics were estimated by ensuring no length changes in ligaments and constant distances between spheres' centres. Two parameters' optimizations were performed; both avoid singularities and one best matches the kinematic patterns off published studies. Sensitivity analysis determined which parameters the models were sensitive to. With both optimization methods, kinematics did not present singularities but correlation values were higher, exceeding 0.6, when matching the published studies. However, ranges of motion (ROM) were different between estimated and published studies. Across participants, models presented large parameter variation. Small variations were found between estimated- and optimized-parameters, and in the estimated-rotations and translations' means and ROM. Model results were sensitive to changes in distal tibia, talus and patella spheres' centres. These models can be implemented in subject-specific rigid-body musculoskeletal models to estimate joint moments and loads.
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http://dx.doi.org/10.1016/j.jbiomech.2016.12.018DOI Listing
February 2017

Exercise and Sports Science Australia (ESSA) position statement on exercise prescription for the prevention and management of osteoporosis.

J Sci Med Sport 2017 May 31;20(5):438-445. Epub 2016 Oct 31.

School of Medical and Health Sciences and the Exercise Medicine Research Institute, Edith Cowan University, Australia; School of Human Movement and Nutrition Sciences, University of Queensland, Australia.

Objectives: Osteoporotic fractures are associated with substantial morbidity and mortality. Although exercise has long been recommended for the prevention and management of osteoporosis, existing guidelines are often non-specific and do not account for individual differences in bone health, fracture risk and functional capacity. The aim of the current position statement is to provide health practitioners with specific, evidence-based guidelines for safe and effective exercise prescription for the prevention or management of osteoporosis, accommodating a range of potential comorbidities.

Design: Position statement.

Methods: Interpretation and application of research reports describing the effects of exercise interventions for the prevention and management of low bone mass, osteoporosis and osteoporotic fracture.

Results: Evidence from animal and human trials indicates that bone responds positively to impact activities and high intensity progressive resistance training. Furthermore, the optimisation of muscle strength, balance and mobility minimises the risk of falls (and thereby fracture), which is particularly relevant for individuals with limited functional capacity and/or a very high risk of osteoporotic fracture. It is important that all exercise programs be accompanied by sufficient calcium and vitamin D, and address issues of comorbidity and safety. For example, loaded spine flexion is not recommended, and impact activities may require modification in the presence of osteoarthritis or frailty.

Conclusions: Specific guidelines for safe and effective exercise for bone health are presented. Individual exercise prescription must take into account existing bone health status, co-morbidities, and functional or clinical risk factors for falls and fracture.
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http://dx.doi.org/10.1016/j.jsams.2016.10.001DOI Listing
May 2017

Long bone robustness during growth: A cross-sectional pQCT examination of children and young adults aged 5-29years.

Bone 2016 12 17;93:71-78. Epub 2016 Sep 17.

Menzies Health Institute Queensland, School of Allied Health Sciences, Griffith University, Gold Coast, Australia.

Skeletal robustness (cross-section size relative to length) is associated with stress fractures in adults, and appears to explain the high incidence of distal radius fractures in adolescents. However, little is known about the ontogeny of long bone robustness during the first three decades of life. Therefore, we explored the ontogeny of tibial, fibular, ulnar and radial robustness in a cross-sectional sample of 5 to 29year-old volunteers of both sexes. Peripheral quantitative computed tomography (pQCT) was used to evaluate cross-sections of the leg (4%, 14%, 38% and 66%), and forearm (4%, and 66%) in N=432 individuals. Robustness was evaluated as the total bone area divided by bone length. Differences between age-groups, sexes, and age-group×sex interactions were evaluated with ANOVA with Tukey's post hocs where appropriate. Most bone sites exhibited more robust bones in men than women (P<0.001 to 0.02), and in older age-groups than younger (P<0.001). Sex×age-group interaction was observed at the 66% and 38% tibia sites with robustness increasing more with age in men than in women (P=0.006 to 0.042). Post-hoc analyses indicated no sex differences prior to 13years-of-age, and notable exceptions to increasing robustness with age at the 4% radial and 66% tibial sites, which exhibited reduced robustness in age groups close to peak height velocity. In conclusion, the present results suggest that very little sexual dimorphism in long bone robustness exists prior to puberty, and that divergence occurs primarily after cessation of longitudinal growth. A period of relative diaphyseal slenderness was identified at age-groups coinciding with the adolescent growth spurt, which may be related to the relatively high incidence of frank and stress fracture in adolescents.
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http://dx.doi.org/10.1016/j.bone.2016.09.015DOI Listing
December 2016

Physical activity estimated by the bone-specific physical activity questionnaire is also associated with cardiovascular risk.

Eur J Sport Sci 2016 Nov 3;16(8):1204-11. Epub 2016 Mar 3.

a School of Allied Health Sciences , Griffith University , Gold Coast , Australia.

The nature of physical activity that benefits bone is traditionally thought to differ from that benefiting cardiovascular health. Accordingly, exercise recommendations for improving bone health and cardiovascular health are largely incongruent. Our aim was to determine the associations between high-impact physical activity participation and both cardiovascular disease risk factors and bone mass. We recruited 94 men and women (age 34.0 ± 13.3 years) to undergo measures of cardiovascular disease risk (BMI, total cholesterol, fasting blood glucose, waist-to-hip ratio, and mean arterial pressure) and dual-energy X-ray absorptiometry (DXA XR-800, Norland) measures of bone mass (femoral neck, lumbar spine, and whole body BMD) and body composition (whole body lean mass and fat mass). Physical activity participation was estimated using the bone-specific physical activity questionnaire (BPAQ). Those in the upper tertile for current BPAQ score exhibited lower total cholesterol, waist-to-hip ratio, and mean arterial pressure than those in the lower tertiles (P < 0.05) with the relationship being mild-to-moderate (r = -0.49 to 0.29, P < 0.01). Those in the upper tertile for BPAQ score also had greater lumbar spine BMD than those in the lower tertile (P = 0.008), with BPAQ score predicting 6% of the variance in BMD (P = 0.02). We conclude that high-impact physical activity as captured by the BPAQ may be beneficial for both bone health and for attenuating cardiovascular disease risk.
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http://dx.doi.org/10.1080/17461391.2016.1153726DOI Listing
November 2016

Trenbolone Improves Cardiometabolic Risk Factors and Myocardial Tolerance to Ischemia-Reperfusion in Male Rats With Testosterone-Deficient Metabolic Syndrome.

Endocrinology 2016 Jan 19;157(1):368-81. Epub 2015 Nov 19.

Heart Foundation Research Centre (D.G.D., G.E.E., A.C.B., J.P.H., E.F.D.T.), Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland 4222, Australia; School of Allied Health Science (B.R.B.), Griffith University, Gold Coast, Queensland 4222, Australia; and Cancer Molecular Pathology (A.K.L.), Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland 4222, Australia.

The increasing prevalence of obesity adds another dimension to the pathophysiology of testosterone (TEST) deficiency (TD) and potentially impairs the therapeutic efficacy of classical TEST replacement therapy. We investigated the therapeutic effects of selective androgen receptor modulation with trenbolone (TREN) in a model of TD with the metabolic syndrome (MetS). Male Wistar rats (n=50) were fed either a control standard rat chow (CTRL) or a high-fat/high-sucrose (HF/HS) diet. After 8 weeks of feeding, rats underwent sham surgery or an orchiectomy (ORX). Alzet miniosmotic pumps containing either vehicle, 2-mg/kg·d TEST or 2-mg/kg·d TREN were implanted in HF/HS+ORX rats. Body composition, fat distribution, lipid profile, and insulin sensitivity were assessed. Infarct size was quantified to assess myocardial damage after in vivo ischaemia reperfusion, before cardiac and prostate histology was performed. The HF/HS+ORX animals had increased sc and visceral adiposity; circulating triglycerides, cholesterol, and insulin; and myocardial damage, with low circulating TEST compared with CTRLs. Both TEST and TREN protected HF/HS+ORX animals against sc fat accumulation, hypercholesterolaemia, and myocardial damage. However, only TREN protected against visceral fat accumulation, hypertriglyceridaemia, and hyperinsulinaemia and reduced myocardial damage relative to CTRLs. TEST caused widespread cardiac fibrosis and prostate hyperplasia, which were less pronounced with TREN. We propose that TEST replacement therapy may have contraindications for males with TD and obesity-related MetS. TREN treatment may be more effective in restoring androgen status and reducing cardiovascular risk in males with TD and MetS.
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http://dx.doi.org/10.1210/en.2015-1603DOI Listing
January 2016

Muscle Size Not Density Predicts Variance in Muscle Strength and Neuromuscular Performance in Healthy Adult Men and Women.

J Strength Cond Res 2016 06;30(6):1577-84

1Centre for Musculoskeletal Research, Menzies Health Institute Queensland, Gold Coast, Australia; 2School of Allied Health Sciences, Griffith University, Gold Coast, Australia; and 3Radboud University, Nijmegen Medical Centre, Nijmegen, the Netherlands.

The purpose of this study was to determine the relationships between peripheral quantitative computed tomography (pQCT)-derived measures of muscle area and density and markers of muscle strength and performance in men and women. Fifty-two apparently healthy adults (26 men, 26 women; age 33.8 ± 12.0 years) volunteered to participate. Dual-energy x-ray absorptiometry (XR-800; Norland Medical Systems, Inc., Trumbull, CT, USA) was used to determine whole body and regional lean and fat tissue mass, whereas pQCT (XCT-3000; Stratec, Pforzheim, Germany) was used to determine muscle cross-sectional area (MCSA) and muscle density of the leg, thigh, and forearm. Ankle plantar flexor and knee extensor strengths were examined using isokinetic dynamometry, and grip strength was examined with dynamometry. Impulse generated during a maximal vertical jump was used as an index of neuromuscular performance. Thigh, forearm, and leg MCSA strongly predicted variance in knee extensor (R = 0.77, p < 0.001) and grip strength (R = 0.77, p < 0.001) and weakly predicted variance in ankle plantar flexor strength (R = 0.20, p < 0.001), respectively, whereas muscle density was only a weak predictor of variance in knee extensor strength (R = 0.18, p < 0.001). Thigh and leg MCSA accounted for 79 and 69% of the variance in impulse generated from a maximal vertical jump (p < 0.001), whereas thigh muscle density predicted only 18% of the variance (p < 0.002). In conclusion, we found that pQCT-derived muscle area is more strongly related to strength and neuromuscular performance than muscle density in adult men and women.
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http://dx.doi.org/10.1519/JSC.0000000000001241DOI Listing
June 2016

Vibration Therapy to Prevent Bone Loss and Falls: Mechanisms and Efficacy.

Authors:
Belinda R Beck

Curr Osteoporos Rep 2015 Dec;13(6):381-9

School of Allied Health Sciences, Griffith University, Gold Coast, QLD, 4222, Australia.

A considerable volume of evidence has accumulated to suggest that whole-body vibration (WBV) may have a therapeutic role to play in the prevention of osteoporotic fracture, particularly for individuals who are unable to tolerate vigorous exercise interventions. There is moderate to strong evidence that WBV will prevent falls (likely due to enhanced neuromuscular function), but also some indication that the effects of WBV do not outstrip those of targeted exercise. Animal data indicates that WBV will also improve bone mass, including preventing loss due to hormone withdrawal, disuse and glucocorticoid exposure. Human trials, however, have produced equivocal outcomes for bone. Positive trends are apparent at the hip and spine, but shortcomings in study designs have limited statistical power. The mechanism of the vibration effect on bone tissue is likely to be mechanical coupling between an oscillating cell nucleus and the cytoskeleton. More robust dose-response human data are required before therapeutic guidelines can be developed.
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http://dx.doi.org/10.1007/s11914-015-0294-8DOI Listing
December 2015