Publications by authors named "James D LeCheminant"

58 Publications

Using generalizability theory and the ERP reliability analysis (ERA) toolbox for assessing test-retest reliability of ERP scores part 2: Application to food-based tasks and stimuli.

Int J Psychophysiol 2021 Feb 27. Epub 2021 Feb 27.

Department of Psychology, Brigham Young University, Provo, UT, United States of America; Neuroscience Center, Brigham Young University, Provo, UT, United States of America.

If an ERP score is to reflect a trait-like characteristic or indicate if an intervention had an effect over time, adequate internal consistency and test-retest reliability of that ERP score across multiple testing sessions must be established. The current paper is a companion paper to Clayson et al. (current issue) that applied generalizability theory formulas and the ERP Reliability Analysis (ERA) Toolbox to assess test-retest and internal consistency in a dataset of event-related brain potentials (ERPs) assessing food-related cognition. Although ERPs in response to food cues have been related to eating behaviors or assessed during a health intervention, the reliability of food-related ERPs generally has not been tested. Within the generalizability theory framework, we assessed the stability (cf., test-retest reliability) and equivalence (cf., internal consistency) of four commonly used food-related ERPs: the late positive potential (LPP), centro-parietal P3, N2, and fronto-central P3. 132 participants (92 female) completed two testing sessions held two weeks apart. During the sessions, participants completed a passive food viewing task, a high-calorie go/no-go task, and a low-calorie go/no-go task in a counterbalanced fashion. Coefficients of equivalence for all ERPs were excellent (>0.96). Coefficients of stability were moderate-to-low, with N2 scores on the low-calorie go/no-go task showing the highest test-retest reliability (>0.65) and fronto-central P3 scores on the high-calorie go/no-go task showing the lowest (0.48). Results suggest the ERPs in the current dataset have high internal consistency and would be reliable in detecting individual differences, but their test-retest reliability is limited. Reliability of these ERPs may be improved with changes in task stimuli, task instructions, and study procedures.
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http://dx.doi.org/10.1016/j.ijpsycho.2021.02.015DOI Listing
February 2021

Physical Activity and Insulin Resistance in 6,500 NHANES Adults: The Role of Abdominal Obesity.

J Obes 2020 26;2020:3848256. Epub 2020 Mar 26.

Department of Nutrition, Dietetics, and Food Science, Brigham Young University, Provo, Utah 84602, USA.

This cross-sectional investigation studied differences in insulin resistance across levels of physical activity in 6,500 US adults who were randomly selected as part of the National Health and Nutrition Examination Survey (NHANES). Another important objective was to determine the influence of abdominal obesity on the physical activity and insulin resistance relationship. MET-minutes were utilized to quantify total activity based on participation in 48 different physical activities. Two strategies were employed to categorize levels of physical activity: one was based on relative MET-minutes (quartiles), and the other approach was based on the US physical activity guidelines. Insulin resistance was indexed using the homeostatic model assessment (HOMA). Abdominal obesity was indexed using waist circumference. Effect modification was tested by dividing waist circumferences into sex-specific quartiles and then evaluating the relationship between physical activity and HOMA-IR within each quartile separately. Results showed that relative physical activity level was associated with HOMA-IR after controlling for demographic and demographic and lifestyle covariates ( = 11.5, < 0.0001 and  = 6.0, =0.0012, respectively). Adjusting for demographic and demographic and lifestyle covariates also resulted in significant relationships between guideline-based activity and HOMA-IR ( = 8.0, < 0.0001 and  = 4.9, =0.0017, respectively). However, statistically controlling for differences in waist circumference with the other covariates nullified the relationship between total physical activity and HOMA-IR. Effect modification testing showed that when the sample was delimited to adults with abdominal obesity (Quartile 4), relative ( = 5.6, =0.0019) and guideline-based physical activity ( = 3.7, =0.0098) and HOMA-IR were significantly associated. Physical activity and HOMA-IR were not related within the other three quartiles. In conclusion, it appears that differences in physical activity may play a meaningful role in insulin resistance in those with abdominal obesity, but total activity does not seem to account for differences in insulin resistance among US adults with smaller waists.
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http://dx.doi.org/10.1155/2020/3848256DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7745049PMC
March 2020

Does inhibitory control training reduce weight and caloric intake in adults with overweight and obesity? A pre-registered, randomized controlled event-related potential (ERP) study.

Behav Res Ther 2021 01 8;136:103784. Epub 2020 Dec 8.

Department of Psychology, Brigham Young University, Provo, UT, 84602, USA; Neuroscience Center, Brigham Young University, Provo, UT, 84602, USA.

A cognitive intervention that may reduce weight and caloric intake is inhibitory control training (ICT; having individuals repeatedly withhold dominant responses to unhealthy food images). We conducted a randomized controlled trial where 100 individuals with overweight or obesity were assigned to complete a generic (n = 48) or food-specific ICT (n = 52) training four times per week for four weeks. Weight and caloric intake were obtained at baseline, four-weeks, and 12-weeks. Participants also completed high-calorie and neutral go/no-go tasks while N2 event-related potential (ERP) data, a neural indicator of inhibitory control, was measured at all visits. Results from mixed model analyses indicate that neither weight, caloric intake, nor N2 ERP component amplitude towards high-calorie foods changed at post-testing or at the 12-week follow up. Regression analyses suggest that individuals with smaller N2 difference amplitudes to food may show greater weight loss and reductions in caloric intake after a generic ICT, while individuals with larger N2 difference amplitudes to food may show greater weight loss and reductions in caloric intake after a food-specific ICT. Overall, multiple food-specific or generic ICT sessions over the course of a four-week period do not affect overall weight loss, caloric intake, or N2 ERP amplitude.
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http://dx.doi.org/10.1016/j.brat.2020.103784DOI Listing
January 2021

To play or not to play? The relationship between active video game play and electrophysiological indices of food-related inhibitory control in adolescents.

Eur J Neurosci 2021 Feb 19;53(3):876-894. Epub 2020 Dec 19.

Department of Exercise Sciences, Brigham Young University, Provo, UT, USA.

Sedentary behaviors, such as computer use and sedentary video games, are barriers to physical activity, contribute to overweight and obesity among adolescents, and can adversely affect eating behaviors. Active video games may increase daily physical activity levels among adolescents and improve food-related inhibitory control. We compared the effects of acute bouts of active and sedentary video gaming on event-related potential (ERP) indices of food-related inhibitory control, energy expenditure, and ad libitum eating. In a within-subjects design, 59 adolescent participants (49% female, M  = 13.29 ± 1.15) completed two separate counterbalanced, 60-min long video gaming sessions separated by seven days. Immediately after, participants completed two go/no-go tasks with high- and low-calorie images and N2 and P3 ERP amplitudes were measured. Participants also completed a Stroop task and were given high- and low-calorie snacks to consume ad libitum. Results indicated that active relative to sedentary video games significantly increased energy expenditure on multiple measures (e.g., METs, heart rate, kcals burned) and participants consumed more calories after the active compared to the sedentary video game session. N2 amplitudes were larger when participants inhibited to high- compared to low-calorie foods, suggesting that high-calorie foods necessitate increased the recruitment of inhibitory control resources; however, there were non-significant differences for the N2 or P3 amplitudes, accuracy or response times, and Stroop performance between active versus sedentary video game sessions. Overall, sixty minutes of active video gaming increased energy expenditure and food consumption but did not significantly alter neural or behavioral measures of inhibitory control to food stimuli.
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http://dx.doi.org/10.1111/ejn.15071DOI Listing
February 2021

The relationship between exercise intensity and neurophysiological responses to food stimuli in women: A randomized crossover event-related potential (ERP) study.

Int J Psychophysiol 2020 12 1;158:349-361. Epub 2020 Nov 1.

Department of Exercise Sciences, Brigham Young University, United States of America. Electronic address:

We tested the effect of different intensities of acute exercise on hunger, and post-exercise energy intake, and neurophysiological measures of attention towards food- and non-food stimuli in women. In a within-subjects crossover design, forty-two women completed no exercise, moderate-intensity exercise, and vigorous-intensity exercise sessions separated by one week, in a counterbalanced fashion. At each session, participants completed a passive viewing task of food (high- and low-calorie) and non-food pictures while electroencephalogram (EEG) data were recorded. The early posterior negativity (EPN), P3, and late positive potential (LPP) components of the event-related potential (ERP) measured neurophysiological responses. Subjective ratings of hunger were measured before and immediately after each condition using a visual analog scale (VAS) and food intake was measured using an ad libitum snack buffet offered at the end of each condition. Results indicated that hunger levels increased as time passed for all sessions. EPN amplitude was larger to non-food compared to food images; P3 amplitude was larger to food than non-food stimuli. LPP amplitude did not differ by high-calorie, low-calorie, or non-food images. Notably, there were no significant main effects or interactions of any ERP component amplitude as a function of exercise intensity. Food intake also did not differ by rest or moderate or vigorous exercise, although subjective arousal ratings to the images were higher after moderate and vigorous exercise compared to rest. Food images also had higher arousal and valence ratings than non-food images overall. Findings indicate that, in this sample, acute moderate and vigorous exercise compared to rest did not disproportionately affect neurophysiological measures of attention to food or non-food stimuli, caloric intake, or hunger.
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http://dx.doi.org/10.1016/j.ijpsycho.2020.10.011DOI Listing
December 2020

World trends in sugar-sweetened beverage and dietary sugar intakes in children and adolescents: a systematic review.

Nutr Rev 2021 02;79(3):274-288

Department of Public Health Nutrition, University of Paderborn, Paderborn, Germany.

Objective: To provide a systematic overview of world dietary sugar and sugar-sweetened beverage (SSB) intake trends in children and adolescents.

Data Sources: Medline, Embase, and the Cochrane Central Register of Controlled Trials in the Cochrane Library were searched through January 2019 to identify longitudinal follow-up studies with time-trend data and repeated cross-sectional studies.

Data Extraction: Data from studies reporting ≥ 2 measurements (sugars, SSB, or sweets/candy) over ≥ 2 years and included ≥ 20 healthy, normal- or overweight children or adolescents aged 1-19 years.

Data Analysis: Data from 43 articles (n = 4 prospective cohort studies; n = 39 repeated cross-sectional studies) from 15 countries (n = 8 European countries plus Australia, Canada, China, South Korea, Mexico, Russia, and the United States) are presented narratively. According to the risk of bias in nonrandomized studies of interventions tool, 34 studies were judged to have a moderate risk of bias, and 5 to have a serious risk of bias.

Conclusions: Consumption among US children and adolescents increased substantially in the decades preceding 2000, followed by a faster and continued decline. As a whole, other international intake trends did not reveal drastic increases and decreases in SSB and dietary sugars; they tended to change only slightly across 3 decades.
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http://dx.doi.org/10.1093/nutrit/nuaa070DOI Listing
February 2021

Does type of active workstation matter? A randomized comparison of cognitive and typing performance between rest, cycling, and treadmill active workstations.

PLoS One 2020 7;15(8):e0237348. Epub 2020 Aug 7.

Department of Psychology, Brigham Young University, Provo, UT, United States of America.

Active workstations are associated with improved health outcomes, but differences in cognitive and typing outcomes between the types of active workstations are unclear. We addressed two main questions: (1) Are there differences in cognitive and typing performance between seated and active workstations? (2) Are there differences in cognitive and typing performance between cycling and treadmill workstations, specifically? Participants included 137 healthy young adults (74 female, mean age = 20.8 years) who completed two sessions. At session one (baseline), all participants completed cognitive and typing tests including the Rey-Auditory Verbal Learning Test, Paced Auditory Serial Addition Test, a typing test, and a flanker task while sitting at rest. At session two, participants were randomized to an active workstation group (treadmill or cycling desk) during which they performed the tests listed above in a randomized fashion, using alternate versions when available. Participants showed significantly better attention and cognitive control scores during the active session as compared to the seated session, but worse verbal memory scores during the active session. Participants were faster and more accurate at typing during the active session relative to the seated session. There were no significant differences between cycling or treadmill workstations on any cognitive or typing outcomes. Improvements during active sessions may be influenced by practice effects, although alternate forms were used when possible. We conclude that active workstations do not seem to largely impact cognitive abilities, with the exception of a slight decrease in verbal memory performance. Findings suggest active workstations, whether walking or cycling, are useful to improve physical activity, particularly when completing tasks that do not require verbal memory recall.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0237348PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7413476PMC
October 2020

The Impact of Step Recommendations on Body Composition and Physical Activity Patterns in College Freshman Women: A Randomized Trial.

J Obes 2019 1;2019:4036825. Epub 2019 Dec 1.

Department of Exercise Sciences, Brigham Young University, Provo, UT, USA.

Purpose: Transitioning from high school to college generally results in reduced physical activity and weight gain at a rate that is higher than the general population. The purpose of this study was to examine the effects of three progressively higher step recommendations over 24 weeks on changes in body weight and body composition.

Methods: Ninety-two freshmen college women wore a multifunction pedometer for 24 weeks after being randomly assigned to a daily step level: 10,000, 12,500, or 15,000. Pedometer data were downloaded every two weeks and participants were counseled on meeting their step recommendation. Body weight and body composition were assessed at baseline and 24 weeks. Body composition was assessed by dual X-ray absorptiometry.

Results: On average, women took 10,786 ± 1501, 12,650 ± 2001, and 13,762 ± 2098 steps per day for the 10,000-, 12,500-, and 15,000-step groups, respectively ( = 15.48, < 0.0001). Participants gained 1.4 ± 2.6, 1.8 ± 2.1, and 1.4 ± 2.1 kg for the 10,000-, 12,500-, and 15,000-step groups, respectively ( = 37.74, < 0.0001). Weight gain was not significantly different between groups ( = 0.18, =0.8385). There was also no difference in fat weight gain ( = 0.41, =0.7954).

Discussion: A step recommendation beyond 10,000 does not prevent weight or fat gain over the first year of college. Future research should focus on either intensity of physical activity or the addition of dietary interventions to prevent weight gain during the first year of college.
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http://dx.doi.org/10.1155/2019/4036825DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6914918PMC
August 2020

Sagittal Abdominal Diameter, Waist Circumference, and BMI as Predictors of Multiple Measures of Glucose Metabolism: An NHANES Investigation of US Adults.

J Diabetes Res 2018 19;2018:3604108. Epub 2018 Jun 19.

Department of Exercise Sciences, College of Life Sciences, Brigham Young University, Provo, UT 84602, USA.

The objective was to compare associations between sagittal abdominal diameter (SAD), waist circumference, and BMI to the oral glucose tolerance test (OGTT), along with fasting glucose, HbA1c, and HOMA-IR, in a nationally representative sample of 3582 US adults. The study also analyzed the effect of multiple covariates on the anthropometric and glucose metabolism associations. A cross-sectional design was used. SAD was assessed using an abdominal caliper. All other data were collected following strict NHANES protocols. The OGTT was the primary variable used to index glucose metabolism. Fasting glucose, HbA1c, and HOMA-IR were also evaluated. Results showed that mean ± SE values were as follows: SAD: 22.3 ± 0.1 cm, waist circumference: 98.0 ± 0.4 cm, BMI: 28.6 ± 0.2 kg/m, OGTT: 113.9 ± 1.0 mg/dL, fasting glucose: 99.6 ± 0.3 mg/dL, HbA1c: 5.4 ± 0.01%, and HOMA-IR: 3.2 ± 0.1. Compared to waist circumference and BMI, SAD consistently emerged as the best predictor of glucose metabolism, before and after adjusting for the covariates, and with the sample stratified by gender, race, or age. SAD was not a better predictor of OGTT among normal-weight adults or non-Hispanic Black adults. Due to the ease of taking SAD measurements, we recommend that healthcare providers use this simple method to more precisely predict diabetes risk, especially among overweight and obese adults.
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http://dx.doi.org/10.1155/2018/3604108DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6029495PMC
December 2018

The utility of event-related potentials (ERPs) in understanding food-related cognition: A systematic review and recommendations.

Appetite 2018 09 19;128:58-78. Epub 2018 May 19.

Department of Psychology, Brigham Young University, Provo, UT 84602, United States; Neuroscience Center, Brigham Young University, Provo, UT 84602, United States.

Daily dietary decisions have the potential to impact our physical, mental, and emotional health. Event-related potentials (ERPs) can provide insight into cognitive processes, such as attention, working memory, and inhibitory control, that may influence the food-related decisions we make on a daily basis. We conducted a systematic review of the food-related cognition and ERP research in order to summarize the extant literature, identify future research questions, synthesize how food-related ERP components relate to eating habits and appetite, and demonstrate the utility of ERPs in examining food-related cognition. Forty-three articles were systematically extracted. In general, results indicated food cues compared to less palatable foods or neutral cues elicited greater ERP amplitudes reflecting early or late attention allocation (e.g., increased P2, P3, late positive potential amplitudes). Food cues were associated with increased frontocentral P3 and N2 ERP amplitudes compared to neutral or less palatable food cues, suggesting increased recruitment of inhibitory control and conflict monitoring resources. However, there was significant heterogeneity in the literature, as experimental tasks, stimuli, and examined ERP components varied widely across studies, and therefore replication studies are needed. In-depth research is also needed to establish how food-related ERPs differ by BMI groups and relate to real-world eating habits and appetite, in order to establish the ecological validity.
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http://dx.doi.org/10.1016/j.appet.2018.05.135DOI Listing
September 2018

A direct comparison between ERP and fMRI measurements of food-related inhibitory control: Implications for BMI status and dietary intake.

Neuroimage 2018 02 4;166:335-348. Epub 2017 Nov 4.

Department of Psychology, Brigham Young University, Provo, UT, 84602, USA; Neuroscience Center, Brigham Young University, Provo, UT, 84602, USA.

Obesity and maintaining a healthy diet have important implications for physical and mental health. One factor that may influence diet and obesity is inhibitory control. We tested how N2 and P3 amplitude, event-related potential (ERP) components that reflect inhibitory control, and functional magnetic resonance imaging (fMRI) activity in brain regions associated with inhibitory control differed toward high- and low-calorie food stimuli across BMI status. We also assessed the relationship between neural indices of food-related inhibitory control and laboratory and daily food intake. Fifty-four individuals (17 normal-weight; 18 overweight; 19 individuals with obesity) completed two food-based go/no-go tasks (one with high- and one with low-calorie foods as no-go stimuli), once during ERP data acquisition and once during fMRI data acquisition. After testing, participants were presented with an ad libitum weighed food buffet. Participants also recorded their food intake using the Automated Self-Administered 24-hour Dietary Recall (ASA24) system across four days. Individuals recruited more inhibitory control when withholding responses towards high-compared to low-calorie foods, although this effect was more consistent for N2 than P3 or fMRI assessments. BMI status did not influence food-related inhibitory control. A larger inhibitory response as measured by N2 amplitude was related to increased ASA24 food intake; P3 amplitude and fMRI region of interest activity did not predict ASA24 intake; neither method predicted food intake from the buffet. ERP and fMRI measurements show similar neural responses to food, although N2 amplitude may be somewhat more sensitive in detecting differences between food types and predicting self-reports of food intake.
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http://dx.doi.org/10.1016/j.neuroimage.2017.11.008DOI Listing
February 2018

In vivo correlates between daily physical activity and intervertebral disc health.

J Orthop Res 2018 05 16;36(5):1313-1323. Epub 2018 Jan 16.

Department of Exercise Sciences, Brigham Young University, Provo, Utah, 84602.

Physical activity impacts health and disease in multiple body tissues including the intervertebral discs. Fluid flow within the disc is an indicator of disc health that can be observed using diffusion weighted magnetic resonance imaging. We monitored activity levels of 26 participants, age 35-55 yrs, using Actigraph accelerometers for 4 days to evaluate vigorous-intensity activity, moderate to vigorous intensity activity, and sedentary time. Participants underwent structural and diffusion weighted magnetic resonance imaging to evaluate intervertebral disc health and fluid flow. They also underwent bone density scans, carotid artery ultrasounds, a treadmill test, and a physical exam for pain, range of motion, and instability. These measures were used to correlate MRI indicators of intervertebral disc health with participant activity levels. Participants with any vigorous-intensity physical activity compared with no vigorous-intensity activity had significantly greater L5/S1 apparent diffusion coefficient values (p = 0.002), corresponding to higher freedom of diffusive movement for cellular nutrients and metabolic waste. Sagittal T2 values in the L5/S1 were also higher (p = 0.004), corresponding to a higher water content in the discs. Higher apparent diffusion coefficients were also found in participants with more than 30 min compared with less than 30 min of daily moderate to vigorous physical activity (p = 0.03), and in participants with less than 67% awake time as sedentary time compared with more than 67% sedentary time (p = 0.03). Increased dynamic loading through physical activity and decreased static loading from sedentary time benefit intervertebral disc health. Physical activity, particularly vigorous activity, is beneficial in helping maintain intervertebral disc health. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1313-1323, 2018.
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http://dx.doi.org/10.1002/jor.23765DOI Listing
May 2018

Brain reactivity to visual food stimuli after moderate-intensity exercise in children.

Brain Imaging Behav 2018 Aug;12(4):1032-1041

Exercise Sciences, Brigham Young University, Provo, UT, 84602, USA.

Exercise may play a role in moderating eating behaviors. The purpose of this study was to examine the effect of an acute bout of exercise on neural responses to visual food stimuli in children ages 8-11 years. We hypothesized that acute exercise would result in reduced activity in reward areas of the brain. Using a randomized cross-over design, 26 healthy weight children completed two separate laboratory conditions (exercise; sedentary). During the exercise condition, each participant completed a 30-min bout of exercise at moderate-intensity (~ 67% HR maximum) on a motor-driven treadmill. During the sedentary session, participants sat continuously for 30 min. Neural responses to high- and low-calorie pictures of food were determined immediately following each condition using functional magnetic resonance imaging. There was a significant exercise condition*stimulus-type (high- vs. low-calorie pictures) interaction in the left hippocampus and right medial temporal lobe (p < 0.05). Main effects of exercise condition were observed in the left posterior central gyrus (reduced activation after exercise) (p < 0.05) and the right anterior insula (greater activation after exercise) (p < 0.05). The left hippocampus, right medial temporal lobe, left posterior central gyrus, and right anterior insula appear to be activated by visual food stimuli differently following an acute bout of exercise compared to a non-exercise sedentary session in 8-11 year-old children. Specifically, an acute bout of exercise results in greater activation to high-calorie and reduced activation to low-calorie pictures of food in both the left hippocampus and right medial temporal lobe. This study shows that response to external food cues can be altered by exercise and understanding this mechanism will inform the development of future interventions aimed at altering energy intake in children.
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http://dx.doi.org/10.1007/s11682-017-9766-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5858994PMC
August 2018

Expanded Normal Weight Obesity and Insulin Resistance in US Adults of the National Health and Nutrition Examination Survey.

J Diabetes Res 2017 25;2017:9502643. Epub 2017 Jul 25.

Department of Exercise Sciences, College of Life Sciences, Brigham Young University, Provo, UT 84602, USA.

This study aims to expand the evaluation of normal weight obesity (NWO) and its association with insulin resistance using an NHANES (1999-2006) sample of US adults. A cross-sectional study including 5983 men and women (50.8%) was conducted. Body fat percentage (BF%) was assessed using dual-energy X-ray absorptiometry. Expanded normal weight obesity (eNWO) categories, pairings of BMI and body fat percentage classifications, were created using standard cut-points for BMI and sex-specific median for BF%. Homeostatic model assessment-insulin resistance (HOMA-IR) levels were used to index insulin resistance. Mean ± SE values were BMI: 27.9 ± 0.2 (women) and 27.8 ± 0.1 (men); body fat percentage: 40.5 ± 0.2 (women) and 27.8 ± 0.2 (men); and HOMA-IR: 2.04 ± 0.05 (women) and 2.47 ± 0.09 (men). HOMA-IR differed systematically and in a dose-response fashion across all levels of the eNWO categories ( = 291.3, < 0.0001). As BMI levels increased, HOMA-IR increased significantly, and within each BMI category, higher levels of body fat were associated with higher levels of HOMA-IR. Both high BMI and high BF% were strongly related to insulin resistance. Insulin resistance appears to increase incrementally according to BMI levels primarily and body fat levels secondarily. Including a precise measure of body fat with BMI adds little to the utility of BMI in the prediction of insulin resistance.
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http://dx.doi.org/10.1155/2017/9502643DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5547730PMC
May 2018

Testing food-related inhibitory control to high- and low-calorie food stimuli: Electrophysiological responses to high-calorie food stimuli predict calorie and carbohydrate intake.

Psychophysiology 2017 Jul 24;54(7):982-997. Epub 2017 Mar 24.

Department of Psychology, Brigham Young University, Provo, Utah.

Maintaining a healthy diet has important implications for physical and mental health. One factor that may influence diet and food consumption is inhibitory control-the ability to withhold a dominant response in order to correctly respond to environmental demands. We examined how N2 amplitude, an ERP that reflects inhibitory control processes, differed toward high- and low-calorie food stimuli and related to food intake. A total of 159 participants (81 female; M age = 23.5 years; SD = 7.6) completed two food-based go/no-go tasks (one with high-calorie and one with low-calorie food pictures as no-go stimuli) while N2 amplitude was recorded. Participants recorded food intake using the Automated Self-Administered 24-hour Dietary Recall system. Inhibiting responses toward high-calorie stimuli elicited a larger (i.e., more negative) no-go N2 amplitude; inhibiting responses toward low-calorie stimuli elicited a smaller no-go N2 amplitude. Participants were more accurate during the high-calorie than low-calorie task, but took longer to respond on go trials toward high-calorie rather than low-calorie stimuli. When controlling for age, gender, and BMI, larger high-calorie N2 difference amplitude predicted lower caloric intake (β = 0.17); low-calorie N2 difference amplitude was not related to caloric intake (β = -0.03). Exploratory analyses revealed larger high-calorie N2 difference amplitude predicted carbohydrate intake (β = 0.22), but not protein (β = 0.08) or fat (β = 0.11) intake. Results suggest that withholding responses from high-calorie foods requires increased recruitment of inhibitory control processes, which may be necessary to regulate food consumption, particularly for foods high in calories and carbohydrates.
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http://dx.doi.org/10.1111/psyp.12860DOI Listing
July 2017

A randomized controlled trial to study the effects of breakfast on energy intake, physical activity, and body fat in women who are nonhabitual breakfast eaters.

Appetite 2017 05 4;112:44-51. Epub 2017 Jan 4.

267 SFH, Provo, UT 84604-2216, USA. Electronic address:

Purpose: The purpose of this study was to determine the effects of eating breakfast on energy intake, physical activity, body weight, and body fat in women who are nonhabitual breakfast eaters over a four-week period.

Methods: Forty-nine women who were nonhabitual breakfast-eaters were randomized to one of two conditions: breakfast or no breakfast. Breakfast eaters were required to eat at least 15% of their daily energy requirement before 8:30 a.m. Non-breakfast eaters did not consume any energy until after 11:30 a.m. Weight and body fat were assessed at baseline and after four weeks of intervention. Body fat was measured by dual energy x-ray absorptiometry (DXA). Participants completed seven 24-hour recalls to assess dietary intake during the intervention. Physical activity was measured by accelerometry for 32 consecutive days.

Results: On average, the participants randomized to eat breakfast consumed 266 ± 496 (F = 12.81; P < 0.01) more calories per day over the course of the study and weighed 0.7 ± 0.8 kg (F = 7.81; p < 0.01) more at the end of the intervention. There was no observed caloric compensation at subsequent meals and no change in self-reported hunger or satiety. There was also no physical activity compensation with the addition of breakfast.

Conclusion: The findings of our study showed that requiring non-breakfast eaters to eat breakfast resulted in higher caloric intake and weight gain. Future research should evaluate this relationship for a longer period of time to see if adding breakfast to the diet of women who generally do not eat breakfast results in adaptive behavior change over time.
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http://dx.doi.org/10.1016/j.appet.2016.12.041DOI Listing
May 2017

Disparity in neural and subjective responses to food images in women with obesity and normal-weight women.

Obesity (Silver Spring) 2017 02 20;25(2):384-390. Epub 2016 Dec 20.

Department of Exercise Sciences, Brigham Young University, Provo, Utah, USA.

Objective: Self-reports tend to differ from objective measurements of food intake, particularly in adults with obesity; however, no studies have examined how neural responses to food (an objective measure) and subjective ratings of food differ by BMI status. This study tested normal-weight women (NWW) and women with obesity (OBW) for group differences in neural indices of attention towards food pictures, subjective ratings of these pictures, and the disparity between objective and subjective measurements.

Methods: Twenty-two NWW (21.8 ± 1.7 kg/m ) and 22 OBW (37.0 ± 5.7 kg/m ) viewed food and flower pictures while late positive potential amplitude, an event-related potential, was recorded. Participants rated pictures for arousal and valence.

Results: Late positive potential amplitude was larger toward food than flower pictures. OBW self-reported flower pictures as more pleasant than food; NWW showed no difference for pleasantness. There were no significant main effects or interactions for arousal. Standardized scores showed that only on subjective, but not objective, measures did OBW compared with NWW disproportionately indicate food pictures as less pleasant than flowers.

Conclusions: Compared with NWW, OBW showed larger discrepancies between neural and subjective reports of attention towards food. Inaccurate self-reports of attention towards food may reduce the efficiency of health interventions.
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http://dx.doi.org/10.1002/oby.21710DOI Listing
February 2017

Medical cost analysis of a school district worksite wellness program.

Prev Med Rep 2016 Jun 26;3:159-65. Epub 2016 Jan 26.

Department of Exercise Sciences, College of Life Sciences, Brigham Young University, Provo, UT, USA.

Objective: To evaluate whether participation in a worksite wellness program differs by age and sex and is associated with frequency and average cost of medical claims.

Methods: Healthcare cost data were available for school district employees during the academic years ending in 2009 through 2014. The wellness program was available in the later 3 years. The frequency and the average cost of medical claims were compared between the 3 years prior to and the 3 years during the wellness program.

Results: Wellness program participation increased from 65.6% 2011-2012 to 79.7% 2012-2013. The increase occurred within age-groups and for males and females. The average age of program participants was significantly lower in 2011-2012 (48.2 vs. 49.4, p = 0.0099), but similar in the next 2 academic years. Participation in at least one behavior change campaign in each year was 52.1%, 53.7%, and 73.7% of all wellness program participants, respectively. Female employees were significantly more likely to complete one or more behavior change campaigns in each year of the wellness program (p < 0.0001). The percentage of employees filing at least one claim per time period was higher for those in the wellness program (p < 0.0001), but average medical claims payments were lower for those in the wellness program. After subtracting program costs, the cost savings from the wellness program was $3,612,402. The benefit-to-cost ratio was 3.6.

Conclusion: Participation in the wellness program resulted in lower average medical claim costs than non-participation but number of claims were higher in program participants.
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http://dx.doi.org/10.1016/j.pmedr.2016.01.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4929144PMC
June 2016

Reduced Sleep Acutely Influences Sedentary Behavior and Mood But Not Total Energy Intake in Normal-Weight and Obese Women.

Behav Sleep Med 2016 Sep-Oct;14(5):528-38. Epub 2015 Oct 20.

a Department of Exercise Sciences , Brigham Young University , Provo , Utah.

Using a crossover design, 22 normal-weight and 22 obese women completed two free-living sleep conditions: (a) Normal Sleep: night of ~8 hr time in bed; and (b) Reduced Sleep: night of < 5 hr time in bed). Outcome measures were energy intake, physical activity and sedentary time, and mood. Sleep time was 7.7 ± 0.3 and 4.8 ± 0.2 hrs during the Normal Sleep and Reduced Sleep conditions, respectively (F = 1791.94; p < 0.0001). Energy intake did not differ between groups or as a function of sleep condition (F = 2.46; p = 0.1244). Sedentary time was ~ 30 min higher after the Reduced Sleep condition (F = 4.98; p = 0.0318); other physical activity outcomes were not different by condition (p > 0.05). Total mood score, depression, anger, vigor, fatigue, and confusion were worse after Reduced Sleep (p < 0.05). Reducing sleep acutely and negatively influenced sedentary time and mood in normal-weight and obese women.
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http://dx.doi.org/10.1080/15402002.2015.1036272DOI Listing
July 2017

Meat Intake and Insulin Resistance in Women without Type 2 Diabetes.

J Diabetes Res 2015 9;2015:174742. Epub 2015 Jul 9.

Department of Exercise Sciences, Brigham Young University, 267 SFH, Provo, UT 84602, USA.

Purpose: To examine the relationship between meat intake and insulin resistance (IR) in 292 nondiabetic women.

Methods: IR was evaluated using the homeostasis model assessment (HOMA). Diet was assessed via 7-day weighed food records. Servings of very lean meat (VLM) and regular meat (meat) were indexed using the ADA Exchange Lists Program. Physical activity was assessed using accelerometers and body fat was measured using the Bod Pod.

Results: Meat intake was directly related to HOMA (F = 7.4; P = 0.007). Women with moderate or high meat intakes had significantly higher HOMA levels than their counterparts. Adjusting for body fat weakened the relationship (F = 1.0; P = 0.3201). Odds ratio results showed that the low meat quartile had 67% lower odds of being IR (75th percentile) compared to their counterparts (OR = 0.33; 95% CI = 0.16-0.71). These findings changed little after adjusting for all covariates simultaneously (OR = 0.34; 95% CI = 0.14-0.83). Conversely, VLM intake was not related to HOMA, with or without the covariates.

Conclusion: Moderate and high meat intakes are associated with increased insulin resistance in nondiabetic women. However, differences in body fat contribute significantly to the relationship. VLM is not predictive of IR. Prudence in the amount and type of meat consumed may be helpful in decreasing the likelihood of IR.
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http://dx.doi.org/10.1155/2015/174742DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4512604PMC
March 2016

Slow walking on a treadmill desk does not negatively affect executive abilities: an examination of cognitive control, conflict adaptation, response inhibition, and post-error slowing.

Front Psychol 2015 27;6:723. Epub 2015 May 27.

Department of Exercise Sciences, Brigham Young University, Provo UT, USA.

An increasing trend in the workplace is for employees to walk on treadmills while working to attain known health benefits; however, the effect of walking on a treadmill during cognitive control and executive function tasks is not well known. We compared the cognitive control processes of conflict adaptation (i.e., congruency sequence effects-improved performance following high-conflict relative to low-conflict trials), post-error slowing (i.e., Rabbitt effect), and response inhibition during treadmill walking (1.5 mph) relative to sitting. Understanding the influence of treadmill desks on these cognitive processes may have implications for worker health and productivity. Sixty-nine individuals were randomized to either a sitting (n = 35) or treadmill-walking condition (n = 34). Groups did not differ in age or body mass index. All participants completed a computerized Eriksen flanker task and a response-inhibition go/no-go task in random order while either walking on a treadmill or seated. Response times (RTs) and accuracy were analyzed separately for each task using mixed model analysis of variance. Separate ANOVAs for RTs and accuracy showed the expected conflict adaptation effects, post-error slowing, and response inhibition effects when collapsed across sitting and treadmill groups (all Fs > 78.77, Ps < 0.001). There were no main effects or interactions as a function of group for any analyses (Fs < 0.79, Ps > 0.38), suggesting no decrements or enhancements in conflict-related control and adjustment processes or response inhibition for those walking on a treadmill versus sitting. We conclude that cognitive control performance remains relatively unaffected during slow treadmill walking relative to sitting.
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http://dx.doi.org/10.3389/fpsyg.2015.00723DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4444606PMC
June 2015

Cognitive and typing outcomes measured simultaneously with slow treadmill walking or sitting: implications for treadmill desks.

PLoS One 2015 15;10(4):e0121309. Epub 2015 Apr 15.

Department of Exercise Sciences, Brigham Young University, Provo, Utah, United States of America.

Purpose: This study compared cognitive (attention, learning, and memory) and typing outcomes during slow treadmill walking or sitting. Seventy-five healthy individuals were randomly assigned to a treadmill walking group (n=37; 23 female) or sitting group (n=38; 17 female).

Methods: The treadmill walking group completed a series of tests while walking at 1.5 mph. The sitting group performed the same tests while sitting at a standard desk. Tests performed by both groups included: the Rey Auditory Verbal Learning Test and a modified version of the Paced Auditory Serial Attention Test. In addition, typing performance was evaluated.

Results: Participants in the treadmill walking group performed worse on the Rey Auditory Verbal Learning Test for total learning than the sitting group; the main effect was significant (F(1,73)=4.75, p=0.03, ηp2=0.06); however, short- and long-delay recall performance did not differ between groups (p>0.05). For the Paced Auditory Serial Attention Test, total number of correct responses was lower in the treadmill walking group relative to the sitting group; the main effect was significant (F(1,73)=4.97, p=0.03, ηp2=0.06). The performance of both groups followed the same learning slope (Group x Trial interactions were not significant) for the Rey Auditory Verbal Learning Test and Paced Auditory Serial Attention Test. Individuals in the treadmill walking group performed significantly worse for all measures of typing (p<0.05).

Conclusion: Walking on a treadmill desk may result in a modest difference in total learning and typing outcomes relative to sitting, but those declines may not outweigh the benefit of the physical activity gains from walking on a treadmill.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0121309PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4398464PMC
January 2016

Neural reactivity to visual food stimuli is reduced in some areas of the brain during evening hours compared to morning hours: an fMRI study in women.

Brain Imaging Behav 2016 Mar;10(1):68-78

Exercise Sciences, Brigham Young University, 106 Smith Fieldhouse, Provo, UT, 84602, USA.

The extent that neural responsiveness to visual food stimuli is influenced by time of day is not well examined. Using a crossover design, 15 healthy women were scanned using fMRI while presented with low- and high-energy pictures of food, once in the morning (6:30-8:30 am) and once in the evening (5:00-7:00 pm). Diets were identical on both days of the fMRI scans and were verified using weighed food records. Visual analog scales were used to record subjective perception of hunger and preoccupation with food prior to each fMRI scan. Six areas of the brain showed lower activation in the evening to both high- and low-energy foods, including structures in reward pathways (P < 0.05). Nine brain regions showed significantly higher activation for high-energy foods compared to low-energy foods (P < 0.05). High-energy food stimuli tended to produce greater fMRI responses than low-energy food stimuli in specific areas of the brain, regardless of time of day. However, evening scans showed a lower response to both low- and high-energy food pictures in some areas of the brain. Subjectively, participants reported no difference in hunger by time of day (F = 1.84, P = 0.19), but reported they could eat more (F = 4.83, P = 0.04) and were more preoccupied with thoughts of food (F = 5.51, P = 0.03) in the evening compared to the morning. These data underscore the role that time of day may have on neural responses to food stimuli. These results may also have clinical implications for fMRI measurement in order to prevent a time of day bias.
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http://dx.doi.org/10.1007/s11682-015-9366-8DOI Listing
March 2016

Health behaviors and work-related outcomes among school employees.

Am J Health Behav 2015 May;39(3):345-51

Brigham Young University, Department of Exercise Sciences, Provo, UT, USA.

Objective: To determine the association between selected health behaviors and work-related outcomes among 2398 school-based employees who voluntarily enrolled in a worksite wellness program.

Methods: This study presents participants' baseline data collected from a personal health assessment used by Well-Steps, a third-party wellness company.

Results: Employees with high levels of exercise, fruit/vegetable consumption, or restful sleep exhibited higher job-performance and job-satisfaction, and lower absenteeism (p < .05). When all 3 behaviors occurred simultaneously, there was higher job-performance (Prevalence Ratio=1.09; 95% CI=1.05-1.13), job-satisfaction (Prevalence Ratio=1.53; 95% CI=1.30-1.80), and lower absenteeism (Prevalence Ratio=1.16; 95% CI=1.08-1.325). Further, number of co-occurring health behaviors influenced other satisfaction and emotional health outcomes.

Conclusion: Selected healthy behaviors, individually or co-occurring, are associated with health outcomes potentially important at the worksite.
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http://dx.doi.org/10.5993/AJHB.39.3.7DOI Listing
May 2015

Dairy consumption and insulin resistance: the role of body fat, physical activity, and energy intake.

J Diabetes Res 2015 29;2015:206959. Epub 2015 Jan 29.

College of Life Sciences, Brigham Young University, Provo, UT 84602, USA.

The relationship between dairy consumption and insulin resistance was ascertained in 272 middle-aged, nondiabetic women using a cross-sectional design. Participants kept 7-day, weighed food records to report their diets, including dairy intake. Insulin resistance was assessed using the homeostatic model assessment (HOMA). The Bod Pod was used to measure body fat percentage, and accelerometry for 7 days was used to objectively index physical activity. Regression analysis was used to determine the extent to which mean HOMA levels differed across low, moderate, and high dairy intake categories. Results showed that women in the highest quartile of dairy consumption had significantly greater log-transformed HOMA values (0.41 ± 0.53) than those in the middle-two quartiles (0.22 ± 0.55) or the lowest quartile (0.19 ± 0.58) (F = 6.90, P = 0.0091). The association remained significant after controlling for each potential confounder individually and all covariates simultaneously. Adjusting for differences in energy intake weakened the relationship most, but the association remained significant. Of the 11 potential confounders, only protein intake differed significantly across the dairy categories, with those consuming high dairy also consuming more total protein than their counterparts. Apparently, high dairy intake is a significant predictor of insulin resistance in middle-aged, nondiabetic women.
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http://dx.doi.org/10.1155/2015/206959DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4325471PMC
October 2015

Adherence to the 2010 Dietary Guidelines for Americans and the relationship to adiposity in young women.

J Nutr Educ Behav 2015 Jan-Feb;47(1):86-93. Epub 2014 Oct 17.

Department of Exercise Sciences, Brigham Young University, Provo, UT.

Objective: To determine the relationship between adherence to the 2010 Dietary Guidelines for Americans and adiposity in young women with and without statistical adjustment for physical activity (PA).

Methods: Participants included 324 young women (aged 17-25 years). The researchers measured dietary intake using the Dietary History Questionnaire and determined diet quality using the 2010 Healthy Eating Index (HEI-2010). BOD POD (Cosmed, Rome, Italy, 2006) and accelerometry were used to assess body fat and PA, respectively.

Results: Women in the top quartile of HEI-2010 had significantly lower percent body fat than women in the lowest 3 quartiles (F = 3.36; P = .03). Controlling for objectively measured PA weakened this relationship by 20%. These young women (top quartile of HEI-2010) also had 0.37 odds (95% confidence interval, 0.16-0.85) of having body fat > 32%.

Conclusions And Implications: Young women whose diets most closely meet the 2010 Dietary Guidelines for Americans have lower adiposity.
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http://dx.doi.org/10.1016/j.jneb.2014.08.011DOI Listing
August 2015

Cardiorespiratory fitness and hip bone mineral density in women: a 6-year prospective study.

Percept Mot Skills 2014 Oct 25;119(2):333-46. Epub 2014 Aug 25.

1 Brigham Young University.

Cross-sectional studies and short term interventions focusing on fitness and bone mineral density (BMD) are common. However, few investigations have studied the effect of fitness on BMD over an extended period of time. The present study was conducted to determine the extent to which cardiorespiratory fitness influences risk of BMD loss at the hip over 6 yr. A prospective cohort design was used with 245 healthy, middle-aged women. Hip BMD was assessed using dual energy x-ray absorptiometry. Calcium and vitamin D were measured using the Block Food Frequency Questionnaire. Menopause status was measured by a questionnaire. Results showed that fit and unfit women experienced similar changes in hip BMD over time. Specifically, unfit women experienced a non-significant 7% increased risk of losing hip BMD compared to their counterparts (RR = 1.07, 95% CI = 0.66, 1.73). Adjusting statistically for differences in age, initial body weight, and hip BMD, weight change, menopause status, calcium and vitamin D intake, and time between assessments had little effect on the relationship. Fitness level did not influence risk of hip BMD loss over time.
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http://dx.doi.org/10.2466/06.10.PMS.119c19z2DOI Listing
October 2014

Examining the Relationship Between Physical Activity Intensity and Adiposity in Young Women.

J Phys Act Health 2015 Jun;12(6):764-9

Background: The purpose of this study was to assess the relationship between intensity of physical activity (PA) and body composition in 343 young women.

Methods: Physical activity was objectively measured using accelerometers worn for 7 days in women 17 to 25 years. Body composition was assessed using the BOD POD.

Results: Young women who spent less than 30 minutes a week performing vigorous PA had significantly higher body fat percentages than women who performed more than 30 minutes of vigorous PA per week (F = 4.54, P = .0113). Young women who spent less than 30 minutes per day in moderate to vigorous PA (MVPA) had significantly higher body fat percentages than those who obtained more than 30 minutes per day of MVPA (F = 7.47, P = .0066). Accumulating more than 90 minutes of MVPA per day was associated with the lowest percent body fat. For every 10 minutes spent in MVPA per day, the odds of having a body fat percentage above 32% decreased by 29% (P = .0002).

Conclusion: Vigorous PA and MVPA are associated with lower adiposity. Young women should be encouraged to accumulate at least 30 minutes of MVPA per day, however getting more than 90 minutes a day is predictive of even lower levels of adiposity.
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http://dx.doi.org/10.1123/jpah.2013-0441DOI Listing
June 2015

Test-retest reliability of the Bod Pod: the effect of multiple assessments.

Percept Mot Skills 2014 Apr;118(2):563-70

The Bod Pod uses air-displacement plethysmography to estimate body fat percentage (BF%). This study was designed to assess the test-retest reliability of the Bod Pod. The study included 283 women (M age = 41.0 yr., SD = 3.0). Each participant was tested at least twice in the Bod Pod. Results showed no significant mean difference between the test and the retest. The intraclass correlation coefficient (ICC) was .991. However, the absolute value of the initial trial differences (absolute mean difference) was .96 (SD = .90). A third assessment of BF% was taken when the initial trial difference was greater than 1 percentage point, and the two closest values were compared. This strategy resulted in a significant decrease in the absolute mean difference, from .96 to .55 percentage point, and ICC increased to .998. The Bod Pod appears to measure body fat percentage reliably; however, findings suggest that multiple trials may be necessary to detect small treatment effects.
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http://dx.doi.org/10.2466/03.PMS.118k15w5DOI Listing
April 2014

Television viewing time and measured cardiorespiratory fitness in adult women.

Am J Health Promot 2015 May-Jun;29(5):285-90. Epub 2014 May 12.

Purpose: This study assessed the relationship between television viewing time and measured cardiorespiratory fitness and the influence of various potential confounders.

Design: Cross-sectional.

Setting: Intermountain West.

Subjects: The sample was composed of 302 nonsmoking women aged 40.2 ± 3.0 years, with ~90% Caucasian and 82% married.

Measures: TV viewing was assessed by using a questionnaire, and cardiorespiratory fitness was measured by using a graded, maximum treadmill test. Physical activity (PA) was evaluated by using accelerometers for 7 days, and body fat percentage (BF%) was measured by using the Bod Pod.

Analysis: Analysis of variance and partial correlation.

Results: VO2max of Frequent (≥3 h/d) TV viewers (32.6 ± 6.4 mL/kg/min) was significantly lower than that of both Moderate (1-2 h/d) (36.2 ± 7.2 mL/kg/min) or Infrequent (<1 h/d) (36.5 ± 6.5 mL/kg/min) viewers (F = 8.0, p = .0004). The Infrequent and Moderate groups did not differ in VO2max. Age, education, body mass index, and season of assessment had no influence on the relationship when controlled statistically. Adjusting for PA (F = 4.2, p = .0157) and BF% (F = 5.0, p = .0071) weakened the relationship by 59% and 58%, respectively, but the relationships remained significant. After controlling for both PA and BF% simultaneously (F = 2.9, p = .0572), the relationship was weakened by 81% and was only borderline significant.

Conclusion: Female Frequent TV viewers have significantly lower cardiorespiratory fitness levels than Moderate or Infrequent viewers. This association appears to be largely a function of differences in levels of PA and BF%.
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http://dx.doi.org/10.4278/ajhp.131107-QUAN-565DOI Listing
December 2016