Publications by authors named "Brendan Egan"

61 Publications

The Between-Competition Running Demands of Elite Hurling Match-Play.

Sports (Basel) 2021 Oct 22;9(11). Epub 2021 Oct 22.

Department of Biomedical Sciences for Health, University of Milan, 20133 Milan, Italy.

The current study aimed to investigate the differences in running demands between the National Hurling League (NHL) and the Championship, and within playing positions. GPS (10 Hz, STATSports Apex GNSS) were used to analyse the running demands during 34 games (2017-2020 seasons) of the Championship and the NHL. The running demands (total-, relative-, high-speed- [>17 km·h] and sprint [≥22 km·h] distance, number and length of sprints, and peak speed) were compared between competitions. Greater total- [ES = 0.32], relative- [ES = 0.26], and sprint-distance [ES = 0.41], and number of sprints [ES = 1.29] were completed in the Championship. The high-speed distance was similar between competitions. Half-backs and half-forwards covered greater total- (ES = 0.91 and 0.21, respectively), relative- (ES = 1.14 and 0.68, respectively), high-speed- (ES = 0.69 and 0.44, respectively), and sprint-distance (ES = 0.50 and 1.26, respectively), number of sprints (ES = 2.66 and 1.73, respectively), and peak speed (ES = 1.09 and 1.32, respectively) in the Championship. There was no difference ( < 0.05) in the sprint distance covered between positions in the Championship. The results showed that the Championship is more physically demanding. The findings present key implications for the transition between competitions.
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http://dx.doi.org/10.3390/sports9110145DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8621312PMC
October 2021

Exercise Training and Circulating Small Extracellular Vesicles: Appraisal of Methodological Approaches and Current Knowledge.

Front Physiol 2021 28;12:738333. Epub 2021 Oct 28.

School of Health and Human Performance, Dublin City University, Dublin, Ireland.

In response to acute exercise, an array of metabolites, nucleic acids, and proteins are enriched in circulation. Collectively termed "exercise factors," these molecules represent a topical area of research given their speculated contribution to both acute exercise metabolism and adaptation to exercise training. In addition to acute changes induced by exercise, the resting profile of circulating exercise factors may be altered by exercise training. Many exercise factors are speculated to be transported in circulation as the cargo of extracellular vesicles (EVs), and in particular, a sub-category termed "small EVs." This review describes an overview of exercise factors, small EVs and the effects of exercise, but is specifically focused on a critical appraisal of methodological approaches and current knowledge in the context of changes in the resting profile small EVs induced by exercise training, and the potential bioactivities of preparations of these "exercise-trained" small EVs. Research to date can only be considered preliminary, with interpretation of many studies hindered by limited evidence for the rigorous identification of small EVs, and the conflation of acute and chronic responses to exercise due to sample timing in proximity to exercise. Further research that places a greater emphasis on the rigorous identification of small EVs, and interrogation of potential bioactivity is required to establish more detailed descriptions of the response of small EVs to exercise training, and consequent effects on exercise adaptation.
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http://dx.doi.org/10.3389/fphys.2021.738333DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8581208PMC
October 2021

Increases in protein intake, protein distribution score, and micronutrient intakes in older adults in response to a whole food-based dietary intervention.

Aging Clin Exp Res 2021 Nov 2. Epub 2021 Nov 2.

School of Health and Human Performance, Dublin City University, Glasnevin, Dublin 9, Ireland.

Background: Changes in nutrient intakes and protein distribution were analyzed in response to a whole food-based dietary intervention targeting high-protein meals in older adults.

Methods: Community-dwelling older adults (n = 56; M/F, 28/28; age, 69.3 ± 4.0 years) completed a 12-week intervention after randomization to exercise only (EX, n = 19), nutrition only (NUTR, n = 16), or nutrition plus exercise (NUTR + EX, n = 21). NUTR and NUTR + EX followed a dietary intervention targeting ~ 0.4 g/kg of protein at each of breakfast, lunch and dinner.

Results: Relative protein intake increased in NUTR (0.99 ± 0.34 to 1.43 ± 0.39 g/kg, P < 0.001) and NUTR + EX (0.90 ± 0.20 to 1.57 ± 0.49 g/kg, P < 0.001). Intakes of cholesterol, B vitamins, selenium and iodine were increased in both NUTR and NUTR + EX (P < 0.05 for all).

Conclusion: This dietary intervention was effective at increasing daily protein intake and achieving an even distribution pattern. Changes in micronutrient intake were marked, and reflect the increase in consumption of animal-derived protein-rich food sources.
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http://dx.doi.org/10.1007/s40520-021-02009-4DOI Listing
November 2021

Endurance exercise training-responsive miR-19b-3p improves skeletal muscle glucose metabolism.

Nat Commun 2021 10 12;12(1):5948. Epub 2021 Oct 12.

Department of Physiology and Pharmacology, Section of Integrative Physiology, Karolinska Institutet, Stockholm, Sweden.

Skeletal muscle is a highly adaptable tissue and remodels in response to exercise training. Using short RNA sequencing, we determine the miRNA profile of skeletal muscle from healthy male volunteers before and after a 14-day aerobic exercise training regime. Among the exercise training-responsive miRNAs identified, miR-19b-3p was selected for further validation. Overexpression of miR-19b-3p in human skeletal muscle cells increases insulin signaling, glucose uptake, and maximal oxygen consumption, recapitulating the adaptive response to aerobic exercise training. Overexpression of miR-19b-3p in mouse flexor digitorum brevis muscle enhances contraction-induced glucose uptake, indicating that miR-19b-3p exerts control on exercise training-induced adaptations in skeletal muscle. Potential targets of miR-19b-3p that are reduced after aerobic exercise training include KIF13A, MAPK6, RNF11, and VPS37A. Amongst these, RNF11 silencing potentiates glucose uptake in human skeletal muscle cells. Collectively, we identify miR-19b-3p as an aerobic exercise training-induced miRNA that regulates skeletal muscle glucose metabolism.
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http://dx.doi.org/10.1038/s41467-021-26095-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8511155PMC
October 2021

Does supplementation with leucine-enriched protein alone and in combination with fish-oil-derived n-3 PUFA affect muscle mass, strength, physical performance, and muscle protein synthesis in well-nourished older adults? A randomized, double-blind, placebo-controlled trial.

Am J Clin Nutr 2021 06;113(6):1411-1427

School of Public Health, Physiotherapy and Sport Science, University College Dublin, Dublin, Ireland.

Background: Leucine-enriched protein (LEU-PRO) and long-chain (LC) n-3 (ω-3) PUFAs have each been proposed to improve muscle mass and function in older adults, whereas their combination may be more effective than either alone.

Objective: The impact of LEU-PRO supplementation alone and combined with LC n-3 PUFAs on appendicular lean mass, strength, physical performance and myofibrillar protein synthesis (MyoPS) was investigated in older adults at risk of sarcopenia.

Methods: This 24-wk, 3-arm parallel, randomized, double-blind, placebo-controlled trial was conducted in 107 men and women aged ≥65 y with low muscle mass and/or strength. Twice daily, participants consumed a supplement containing either LEU-PRO (3 g leucine, 10 g protein; n = 38), LEU-PRO plus LC n-3 PUFAs (0.8 g EPA, 1.1 g DHA; LEU-PRO+n-3; n = 38), or an isoenergetic control (CON; n = 31). Appendicular lean mass, handgrip strength, leg strength, physical performance, and circulating metabolic and renal function markers were measured pre-, mid-, and postintervention. Integrated rates of MyoPS were assessed in a subcohort (n = 28).

Results: Neither LEU-PRO nor LEU-PRO+n-3 supplementation affected appendicular lean mass, handgrip strength, knee extension strength, physical performance or MyoPS. However, isometric knee flexion peak torque (treatment effect: -7.1 Nm; 95% CI: -12.5, -1.8 Nm; P < 0.01) was lower postsupplementation in LEU-PRO+n-3 compared with CON. Serum triacylglycerol and total adiponectin concentrations were lower, and HOMA-IR was higher, in LEU-PRO+n-3 compared with CON postsupplementation (all P < 0.05). Estimated glomerular filtration rate was higher and cystatin c was lower in LEU-PRO and LEU-PRO+n-3 postsupplementation compared with CON (all P < 0.05).

Conclusions: Contrary to our hypothesis, we did not observe a beneficial effect of LEU-PRO supplementation alone or combined with LC n-3 PUFA supplementation on appendicular lean mass, strength, physical performance or MyoPS in older adults at risk of sarcopenia. This trial was registered at clinicaltrials.gov as NCT03429491.
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http://dx.doi.org/10.1093/ajcn/nqaa449DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8168361PMC
June 2021

Increased Leg Strength After Concurrent Aerobic and Resistance Exercise Training in Older Adults Is Augmented by a Whole Food-Based High Protein Diet Intervention.

Front Sports Act Living 2021 26;3:653962. Epub 2021 Mar 26.

School of Health and Human Performance, Dublin City University, Dublin, Ireland.

Most studies in older adults have utilized powdered protein supplements or oral nutrition solutions as a source of additional dietary protein, but whole foods may provide a greater anabolic stimulus than protein isolated from food matrices. Therefore, the present study investigated a concurrent aerobic and resistance exercise training program in older adults, in the absence or presence of a high protein whole food-based dietary intervention, for effects on strength, physical function, and body composition. Community-dwelling older adults ( = 56; M/F, 28/28; age, 69.3 ± 4.0 years; BMI, 26.6 ± 3.7 kg m) participated in a 12-week intervention after randomization to either nutrition only (NUTR; = 16), exercise only (EX, = 19), or nutrition plus exercise (NUTR + EX, = 21) groups. NUTR and NUTR + EX followed a dietary intervention targeting an increase in protein-rich meals at breakfast, lunch, and dinner. Exercise training in EX and NUTR + EX consisted of 24 min sessions of concurrent aerobic and resistance exercise performed three times per week. Daily protein intake increased in NUTR and NUTR + EX, but not EX. The increase in 1RM leg press strength was greater (Interaction effect, = 0.012) in NUTR + EX [29.6 (18.1, 41.0) kg] than increases observed in NUTR [11.1 (-1.3, 23.6) kg] and EX [12.3 (0.9, 23.8) kg]. The increase in 1RM chest press strength was greater (interaction effect, = 0.031) in NUTR + EX [6.3 (4.0, 8.6) kg] than the increase observed in NUTR [2.9 (0.3, 5.5) kg], but not EX [6.3 (3.9, 8.7) kg]. Hand-grip strength and sit-to-stand performance were each improved in all three groups, with no differences observed between groups (interaction effect, = 0.382 and = 0.671, respectively). An increase in percentage body fat was observed in NUTR, but not in EX or NUTR + EX (interaction effect, = 0.018). No between-group differences were observed for change in lean body mass (interaction effect, = 0.402). Concurrent aerobic and resistance exercise training improves strength and physical function in older adults, but combining this training with an increase in daily protein intake through whole foods may be advantageous to increase lower limb strength.
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http://dx.doi.org/10.3389/fspor.2021.653962DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8034230PMC
March 2021

Changes in body composition and substrate utilization after a short-term ketogenic diet in endurance-trained males.

Biol Sport 2021 Mar 30;38(1):145-152. Epub 2020 Aug 30.

School of Health and Human Performance, Dublin City University, Ireland.

Few studies have investigated the short-term effects of a very low carbohydrate ketogenic diet (KD) on body composition and substrate utilization in trained individuals. This study investigated effects on substrate utilization during incremental exercise, and changes in body composition, in response to seven days ad libitum consumption of a KD by athletes from endurance sports. Nine young trained males (age, 21.8 ± 1.9 y; height, 1.83 ± 0.11 m; body mass, 78.4 ± 13.8 kg; body fat, 14.9 ± 3.9%; VO2peak, 54.3 ± 5.9 mL kg min) were assessed before (day 0; PRE) and after (day 7; POST) seven days of consuming an ad libitum KD. Following an overnight fast, body composition was measured by dual x-ray absorptiometry, and substrate utilization was measured during an incremental (3 min stages, 35 W increments) exercise test on a cycle ergometer. After KD, W (PRE, 295 ± 30 W; POST, 292 ± 38 W) and VO2peak (PRE, 4.18 ± 0.33 L min; POST, 4.10 ± 0.43 L min) were unchanged, whereas body mass [-2.4 (-3.2, -1.6) kg; P < 0.001, d = 0.21], fat mass [-0.78 (-1.10, -0.46) kg; P < 0.001, d = 0.22] and fat-free mass (FFM) [-1.82 (-3.12, -0.51) kg; P = 0.013, d = 0.22] all decreased. The respiratory exchange ratio was lower, and rates of fat oxidation were higher, at POST across a range of exercise intensities. Maximal fat oxidation rate was ~1.8-fold higher after KD (PRE, 0.54 ± 0.13 g min; POST, 0.95 ± 0.24 g min; P < 0.001, d = 2.2). Short-term KD results in loss of both fat mass and FFM, increased rates of fat oxidation and a concomitant reduction in CHO utilization even at moderate-to-high intensities of exercise.
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http://dx.doi.org/10.5114/biolsport.2020.98448DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7996378PMC
March 2021

Comparison of hot water immersion at self-adjusted maximum tolerable temperature, with or without the addition of salt, for rapid weight loss in mixed martial arts athletes.

Biol Sport 2021 Mar 7;38(1):89-96. Epub 2020 Aug 7.

School of Health and Human Performance, Dublin City University, Dublin, Ireland.

Hot water immersion is used by athletes in weight category sports to produce rapid weight loss (RWL) by means of passive fluid loss, and often is performed with the addition of Epsom salts (magnesium sulphate). This study investigated the magnitude of body mass losses during hot water immersion with or without the addition of salt, with the temperature commencing at 37.8°C and being self-adjusted by participants to their maximum tolerable temperature. In a crossover design, eight male MMA athletes (29.4 ± 5.3 y; 1.83 ± 0.05 m; 85.0 ± 4.9 kg) performed a 20 min whole-body immersion followed by a 40 min wrap in a warm room, twice in sequence per visit. During one visit, only fresh water was used (FWB), and in the other visit, magnesium sulphate (1.6% wt/vol) was added to the bath (SWB). Prior to each visit, 24 h of carbohydrate, fibre and fluid restriction was undertaken. Water temperatures at the end of the first and second baths were ~39.0°C and ~39.5°C, respectively. Body mass losses induced by the hot bath protocols were 1.71 ± 0.70 kg and 1.66 ± 0.78 kg for FWB and SWB, respectively (P = 0.867 between trials, d = 0.07), and equivalent to ~2.0% body mass. Body mass lost during the entire RWL protocol was 4.5 ± 0.7%. Under the conditions employed, the magnitude of body mass lost in SWB was similar to FWB. Augmenting passive fluid loss during hot water immersion with the addition of salt may require a higher salt concentration than that presently utilised.
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http://dx.doi.org/10.5114/biolsport.2020.96947DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7996375PMC
March 2021

Effects of a Long Chain n-3 Polyunsaturated Fatty Acid-rich Multi-ingredient Nutrition Supplement on Body Composition and Physical Function in Older Adults with Low Skeletal Muscle Mass.

J Diet Suppl 2021 Mar 24:1-16. Epub 2021 Mar 24.

School of Health and Human Performance, Dublin City University, Dublin 9, Ireland.

Six months of supplementation with a multi-ingredient nutrition supplement was investigated in older adults with low skeletal muscle mass given the recently purported benefits of such approaches. Community-dwelling older adults (age, 74.9 ± 3.6 y; M/F, 18/19) participated in a double-blind, placebo-controlled, randomized trial involving daily consumption of either fruit juice placebo (PLA) or supplement (SUPP) in the form of a 200-mL carton of a juice-based emulsion of long chain n-3 polyunsaturated fatty acids (LC n-3 PUFA) (3000 mg as 1500 mg docosahexaenoic acid and 1500 mg eicosapentaenoic acid), whey protein isolate (8 g), vitamin D3 (400 IU), and resveratrol (150 mg). Body composition, physical function, and circulating markers of metabolic health were assessed at baseline (PRE), and after 3 (MID) and 6 (POST) months of supplementation. Lean body mass (LBM) was unchanged in either group, but fat mass increased in SUPP by 1.41 (0.75, 2.07) kg at POST (+6.4%;  < .001;  = 0.20). Hand-grip strength was maintained in SUPP, but declined in PLA by 2.50 (0.81, 4.19) kg at POST (-6.8%;  = .002;  = 0.38). Short physical performance battery score was unchanged in PLA, but increased in SUPP by 1.13 (0.41, 1.84) above PRE at POST ( = .001;  = 0.47). Circulating markers of metabolic health were unchanged in response to the intervention in either PLA or SUPP. Long-term supplementation with an LC n-3 PUFA-rich multi-ingredient nutrition supplement demonstrates potential efficacy for improving physical function in older adults in the absence of exercise training and independent of a change in LBM.
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http://dx.doi.org/10.1080/19390211.2021.1897057DOI Listing
March 2021

A Fish-Derived Protein Hydrolysate Induces Postprandial Aminoacidaemia and Skeletal Muscle Anabolism in an In Vitro Cell Model Using Ex Vivo Human Serum.

Nutrients 2021 Feb 17;13(2). Epub 2021 Feb 17.

Department of Physical Education and Sport Sciences, Faculty of Education and Health Sciences, University of Limerick, V94 T9PX Limerick, Ireland.

Fish-derived proteins, particularly fish protein hydrolysates (FPH), offer potential as high-quality sources of dietary protein, whilst enhancing economic and environmental sustainability. This study investigated the impact of a blue whiting-derived protein hydrolysate (BWPH) on aminoacidaemia in vivo and skeletal muscle anabolism in vitro compared with whey protein isolate (WPI) and an isonitrogenous, non-essential amino acid (NEAA) control (0.33 g·kg·body mass) in an ex vivo, in vitro experimental design. Blood was obtained from seven healthy older adults (two males, five females; age: 72 ± 5 years, body mass index: 24.9 ± 1.6 kg·m) in three separate trials in a randomised, counterbalanced, double-blind design. C2C12 myotubes were treated with ex vivo human serum-conditioned media (20%) for 4 h. Anabolic signalling (phosphorylation of mTOR, p70S6K, and 4E-BP1) and puromycin incorporation were determined by immunoblotting. Although BWPH and WPI both induced postprandial essential aminoacidaemia in older adults above the NEAA control, peak and area under the curve (AUC) leucine and essential amino acids were more pronounced following WPI ingestion. Insulin was elevated above baseline in WPI and BWPH only, a finding reinforced by higher peak and AUC values compared with NEAA. Muscle protein synthesis, as measured by puromycin incorporation, was greater after incubation with WPI-fed serum compared with fasted serum ( = 0.042), and delta change was greater in WPI ( = 0.028) and BWPH ( = 0.030) compared with NEAA. Myotube hypertrophy was greater in WPI and BWPH compared with NEAA (both = 0.045), but was similar between bioactive conditions ( = 0.853). Taken together, these preliminary findings demonstrate the anabolic potential of BWPH in vivo and ex vivo, thus providing justification for larger studies in older adults using gold-standard measures of acute and chronic MPS in vivo.
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http://dx.doi.org/10.3390/nu13020647DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7922518PMC
February 2021

Case Study: Transition to a Vegan Diet in an Elite Male Gaelic Football Player.

Sports (Basel) 2021 Jan 5;9(1). Epub 2021 Jan 5.

School of Health and Human Performance, Dublin City University, Dublin 9, Ireland.

Vegan diets are increasingly of interest to athletes, but require a well-planned approach in order to mitigate the risk of potential adverse effects on nutrient intakes, and consequently performance. This case study reports the process of an elite male Gaelic football player (age 25 years; height, 1.88 m; body mass, 87.8 kg; lean body mass, 73.26 kg; body fat, 11.3%) transitioning from an omnivorous diet to a vegan diet at the beginning of a competitive season. The report encompasses key considerations in the planning and provision of nutrition support in this context, in addition to iterations needed based on challenges presented by the athlete. Analysis of nutrient intake (Nutritics Dietary Analysis Software), body composition (dual X-ray absorptiometry; Lunar iDXA, GE Healthcare), and running performance during match-play (global positioning system-based tracking; STATSports Apex) each indicated that with adequate knowledge and education, and appropriate planning, commitment and iterative feedback, the athlete was able to meet nutrition targets on a vegan diet without compromising key performance indicators compared to the omnivorous diet of the previous season. We anticipate that this case study will assist practitioners to recognize the key considerations to address when working with athletes transitioning to a vegan diet.
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http://dx.doi.org/10.3390/sports9010006DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7824752PMC
January 2021

Effects of 8 wk of 16:8 Time-restricted Eating in Male Middle- and Long-Distance Runners.

Med Sci Sports Exerc 2021 03;53(3):633-642

School of Health and Human Performance, Dublin City University, Dublin, IRELAND.

Purpose: Eight weeks of time-restricted eating (TRE) in concert with habitual exercise training was investigated for effects on body composition, energy and macronutrient intakes, indices of endurance running performance, and markers of metabolic health in endurance athletes.

Methods: Male middle- and long-distance runners (n = 23) were randomly assigned to TRE (n = 12) or habitual dietary intake (CON; n = 11). TRE required participants to consume all of their dietary intake within an 8-h eating window (so-called 16:8 TRE), but dietary patterns, food choices, and energy intake were ad libitum during this window. Participants continued their habitual training during the intervention period. Participants completed an incremental exercise test before (PRE) and after (POST) the 8-wk intervention for the assessment of blood lactate concentrations, running economy, and maximal oxygen uptake. Fasted blood samples were analyzed for glucose, insulin, and triglyceride concentrations. Dietary intake was assessed at PRE, MID (week 4), and POST using a 4-d semiweighed food diary.

Results: Seventeen participants (TRE, n = 10; CON, n = 7) completed the intervention. Training load did not differ between groups for the duration of the intervention period. TRE resulted in a reduction in body mass (mean difference of -1.92 kg, 95% confidence interval = -3.52 to -0.32, P = 0.022). Self-reported daily energy intake was lower in TRE at MID and POST (group-time interaction, P = 0.049). No effect of TRE was observed for oxygen consumption, respiratory exchange ratio, running economy, blood lactate concentrations, or heart rate during exercise, nor were there any effects on glucose, insulin, or triglyceride concentrations observed.

Conclusion: Eight weeks of 16:8 TRE in middle- and long-distance runners resulted in a decrease in body mass commensurate with a reduction in daily energy intake, but it did not alter indices of endurance running performance or metabolic health.
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http://dx.doi.org/10.1249/MSS.0000000000002488DOI Listing
March 2021

Nutritional Ketosis with Ketogenic Diets or Exogenous Ketones: Features, Convergence, and Divergence.

Curr Sports Med Rep 2020 Jul;19(7):251-259

Department of Molecular Pharmacology and Physiology, University of South Florida, Tampa, FL.

Athletes, clinicians, and practitioners are increasingly interested in the proposed performance and therapeutic benefits of nutritional ketosis (NK). NK is best operationally defined as a nutritionally induced metabolic state resulting in blood β-hydroxybutyrate concentrations of ≥0.5 mM. Most tissues readily metabolize ketone bodies (KBs), and KBs in turn regulate metabolism and signaling in both a systemic and tissue-specific manner. During fasting, starvation, or ketogenic diets, endogenous synthesis of KBs is amplified resulting in a state of NK. Orally administered exogenous ketone supplements rapidly elevate circulating KBs and produce a similar, but far from identical, metabolic state. NK results in a number of convergent features regardless of endogenous or exogenous induction; however, important differences also are observed. The implications of NK across health, disease, and performance is rapidly becoming more evident, thus acknowledging the convergent and divergent features of NK is critical for fully understanding the potential utility of this metabolic state.
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http://dx.doi.org/10.1249/JSR.0000000000000732DOI Listing
July 2020

Acute ingestion of beetroot juice does not improve short-duration repeated sprint running performance in male team sport athletes.

J Sports Sci 2020 Sep 7;38(18):2063-2070. Epub 2020 Jun 7.

UCD Institute for Sport & Health, School of Public Health, Physiotherapy, and Sports Science, University College Dublin , Dublin, Ireland.

The effects of acute ingestion of nitrate on short-duration repeated sprint performance (RSP) are unclear. This study investigated the effect of acute ingestion of beetroot juice on a test of RSP in team sport athletes. Sixteen male team sport athletes undertook four trials using a 40 m maximum shuttle run test (MST), which incorporates 10 × 40 m shuttle sprints with 30 s between the start of each sprint. Two familiarisation trials, followed by nitrate-rich beetroot juice (BR; ~6 mmol nitrate) and nitrate-depleted beetroot juice (PLA; ~0.0034 mmol nitrate) trials were completed in a randomised, double-blind manner. Ingestion of beetroot juice 3 h prior to exercise elevated plasma nitrate concentrations ~6-fold in BR (BR, 413 ± 56 μM; PLA, 69 ± 30 μM; P < 0.001). RSP, assessed by sprint performance decrement (S; %), did not differ (P = 0.337) between BR (5.31 ± 2.49%) and PLA (5.71 ± 2.61%). There was no difference between trials for total sprint time (P = 0.806), fastest sprint (P = 0.341), slowest sprint (P = 0.787), or post-exercise blood lactate concentration (BR, 11.8 ± 2.5 mM; PLA, 12.2 ± 2.3 mM; P = 0.109). Therefore, acute ingestion of beetroot juice did not improve a test of short-duration RSP in team sport athletes.
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http://dx.doi.org/10.1080/02640414.2020.1770409DOI Listing
September 2020

Comparison of hot water immersion at 37.8°C with or without salt for rapid weight loss in mixed martial arts athletes.

J Sports Sci 2020 Mar 30;38(6):607-611. Epub 2020 Jan 30.

School of Health and Human Performance, Dublin City University, Dublin, Ireland.

Hot water immersion, known as a hot bath, is used by MMA athletes to produce rapid weight loss (RWL) by means of passive fluid loss. This study investigated the magnitude of body mass losses using a standardized hot bath protocol with or without the addition of salt. In a crossover design, eleven male MMA athletes (28.5 ± 4.6 y; 1.83 ± 0.07 m; 82.5 ± 9.1 kg) performed a 20-min immersion at 37.8°C followed by a 40-min wrap in a warm room. This bath and wrap was performed twice per visit. During one visit, only fresh water was used (FWB), and in the other visit, magnesium sulphate (1.6% wt/vol) was added to the bath (SWB). Prior to each visit, 24 h of carbohydrate, fibre, and fluid restriction was undertaken as part of the RWL protocol. Body mass losses induced by the hot bath protocols were 1.63 ± 0.75 kg and 1.60 ± 0.80 kg for FWB and SWB, respectively, and equivalent to ~2.1% body mass. Under the conditions employed, the magnitude of body mass loss in SWB was similar to FWB. However, further research should explore bathing in a temperature that is consistent with that habitually used by fighters, and/or higher concentrations of salt.
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http://dx.doi.org/10.1080/02640414.2020.1721231DOI Listing
March 2020

Longitudinal Study of Maternal BMI in Successive Pregnancies.

Obesity (Silver Spring) 2020 02;28(2):460-467

UCD Centre for Human Reproduction, Coombe Women & Infants University Hospital, Dublin, Ireland.

Objective: This longitudinal observational study examined BMI changes between successive pregnancies.

Methods: The computerized medical records of women who attended a large maternity hospital between 2009 and 2017 for their first and second singleton deliveries were analyzed. Women who had their weight first measured after 15 weeks of gestation in either pregnancy were excluded.

Results: Of the 9,724 women, the incidence of obesity increased from 11.6% in the first pregnancy to 16.0% in the second. The mean interpregnancy interval was 32.5 ± 15.7 months, and median BMI change was +0.6 kg/m (interquartile range 2.2; P < 0.001). Overall, 10.3% (1,006/9,724) developed overweight and 5.9% (571/9,724) developed obesity by the second pregnancy. Of the nulliparas in the overweight category, 20.6% (526/2,558) entered the obesity category. The development of obesity by the second pregnancy was independently associated with a longer interpregnancy interval, formula feeding at hospital discharge, taking antidepressants or anxiolytics, and postnatal depression. Professional/managerial employment was associated with a lower odds ratio of developing obesity.

Conclusions: Maternal obesity increased between the first and second pregnancy, with one-fifth of nulliparas in the overweight category developing obesity. Pregnancy-related factors were identified as predictors of developing obesity. Further research is needed to assess whether interventions targeting these related factors could optimize maternal weight management between pregnancies.
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http://dx.doi.org/10.1002/oby.22707DOI Listing
February 2020

Maternal Weight Trajectories in Successive Pregnancies and Their Association With Gestational Diabetes Mellitus.

Diabetes Care 2020 03 16;43(3):e33-e34. Epub 2020 Jan 16.

UCD Centre for Human Reproduction, Coombe Women and Infants University Hospital, Dublin, Ireland.

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http://dx.doi.org/10.2337/dc19-2274DOI Listing
March 2020

Self-Reported Prevalence, Magnitude, and Methods of Rapid Weight Loss in Male and Female Competitive Powerlifters.

J Strength Cond Res 2020 Jan 3. Epub 2020 Jan 3.

School of Health and Human Performance, Dublin City University, Dublin, Ireland.

Nolan, D, Lynch, AE, and Egan, B. Self-reported prevalence, magnitude, and methods of rapid weight loss in male and female competitive powerlifters. J Strength Cond Res XX(X): 000-000, 2019-Rapid weight loss (RWL) is common practice in weight category sports, but no empirical data exist documenting the weight-making practices of competitive strength athletes. This study investigated the self-reported prevalence, magnitude, and methods of RWL used by male and female powerlifters when preparing for competition. Competitive powerlifters (n = 321; M/F, 194/127) completed an anonymous online questionnaire previously validated for assessment of methods of RWL. Respondents were categorized by their federation's respective antidoping policy, weigh-in procedure, and degree of assistive equipment allowed, in addition to their use or not of RWL. Subgroup analyses were performed on the largest category of respondents (n = 200, M/F, 117/83; ≤2-hour weigh-in, drug-tested, "raw") based on sex, weight category, and competitive status. Prevalence of RWL was 85.8%, with an average RWL of 3.0 ± 1.9% body mass and an RWL score of 25.1 ± 7.4. Neither sex nor weight category influenced the RWL score, but in male athletes, a lower RWL score (22.7 ± 6.3) was reported in athletes in the lowest tertile of the Wilks score (p = 0.015). Frequencies of "always use" were reported as 54.0% for fluid restriction and 49.0% for water loading. Coaches (37.5%) and online resources (35.0%) were "very influential" on RWL practices in these athletes, while doctors (85.5%) and dieticians (63.0%) were reported to be "not influential." The prevalence of RWL is high in competitive powerlifting, and the methods used are akin to other weight category sports, but the reported RWL scores are lower than reported in combat sports with longer recovery periods after weigh-in.
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http://dx.doi.org/10.1519/JSC.0000000000003488DOI Listing
January 2020

Exogenous Ketone Salts Do Not Improve Cognitive Performance During a Dual-Stress Challenge.

Int J Sport Nutr Exerc Metab 2019 Nov 21:1-8. Epub 2019 Nov 21.

Texas State University.

In the present study, our team aimed to investigate the effects of acute ingestion of a ketone salt (KS) supplement on the cognitive performance in healthy college-aged males during a dual-stress challenge (DSC). Following a peak oxygen uptake test and DSC familiarization, 16 males completed a DSC while cycling at 60% of their respective peak oxygen uptake after ingesting either a commercially available racemic (D- and L-)β-hydroxybutyrate (β-OHB) KS (0.38 g/kg body mass) or a placebo, using a triple-blinded, crossover, and counterbalanced design. The participants consumed the KS or placebo at -60 and -15 min prior to the start of the DSC. Heart rate, rating of perceived exertion, and blood β-OHB and glucose were sampled throughout. The DSC consisted of a mental arithmetic challenge and a modified Stroop Color Word, which alternated every 2 min for 20 min. Upon completion of the DSC, responses for correct, incorrect, and no responses were recorded for the mental arithmetic challenge and Stroop Color Word. Blood β-OHB was elevated with KS by -15 min and remained so throughout (p < .001), peaking at 0.76 ± 0.32 mM. Blood glucose was lower with KS compared with the placebo at -15 and 10 min by 9% and 5%, respectively (both ps < .05). There were no differences between the treatments for heart rate, rating of perceived exertion, mental arithmetic challenge, or Stroop Color Word. Overall, this study suggests that KSs are not effective aids for enhancing cognitive performance during a DSC, which might partially be explained by the inability of currently available commercial KS supplements to elevate β-OHB blood concentrations above ∼1.0 mM.
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http://dx.doi.org/10.1123/ijsnem.2019-0122DOI Listing
November 2019

No Benefit of Ingestion of a Ketone Monoester Supplement on 10-km Running Performance.

Med Sci Sports Exerc 2019 12;51(12):2506-2515

School of Health and Human Performance, Dublin City University, Glasnevin, Dublin, IRELAND.

Purpose: Preexercise ingestion of exogenous ketones alters the metabolic response to exercise, but effects on exercise performance have been equivocal.

Methods: On two occasions in a double-blind, randomized crossover design, eight endurance-trained runners performed 1 h of submaximal exercise at approximately 65% V˙O2max immediately followed by a 10-km self-paced time trial (TT) on a motorized treadmill. An 8% carbohydrate-electrolyte solution was consumed before and during exercise, either alone (CHO + PLA), or with 573 mg·kg of a ketone monoester supplement (CHO + KME). Expired air, HR, and RPE were monitored during submaximal exercise. Serial venous blood samples were assayed for plasma glucose, lactate, and β-hydroxybutyrate concentrations.

Results: CHO + KME produced plasma β-hydroxybutyrate concentrations of approximately 1.0 to 1.3 mM during exercise (P < 0.001), but plasma glucose and lactate concentrations were similar during exercise in both trials. V˙O2, running economy, respiratory exchange ratio, HR, and RPE were also similar between trials. Performance in the 10-km TT was not different (P = 0.483) between CHO + KME (mean, 2402 s; 95% confidence interval, 2204-2600 s) and CHO + PLA (mean, 2422 s; 95% confidence interval, 2217-2628 s). Cognitive performance, measured by reaction time and a multitasking test, did not differ between trials.

Conclusions: Compared with carbohydrate alone, coingestion of KME by endurance-trained athletes elevated plasma β-hydroxybutyrate concentrations, but did not improve 10-km running TT or cognitive performance.
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http://dx.doi.org/10.1249/MSS.0000000000002065DOI Listing
December 2019

Exercise Maintenance in Older Adults 1 Year After Completion of a Supervised Training Intervention.

J Am Geriatr Soc 2020 01 24;68(1):163-169. Epub 2019 Oct 24.

School of Health and Human Performance, Dublin City University, Dublin, Ireland.

Background/objective: Barriers and facilitators of exercise maintenance and residual effects of exercise training intervention on physical and cognitive function after the cessation of training are inadequately described in older adults.

Design And Setting: One year after the cessation of a supervised exercise training intervention, a mixed methods approach employed a quantitative phase that assessed body composition and physical and cognitive function and a qualitative phase that explored determinants of exercise maintenance after participation in the intervention.

Participants: Community-dwelling older Irish adults (aged >65 years) who had completed 12 weeks of supervised exercise training 1 year previously.

Measurements: Fifty-three participants (male/female ratio = 30:23; age = 70.8 ± 3.9 years) completed the follow-up testing comprising body composition and physical and cognitive function. Semistructured interviews were conducted with 12 participants (male/female ratio = 6:6) using the Theoretical Domains Framework to inform the interview guide.

Results: At 1 year follow-up, body fat increased (mean = 4.3%; 95% confidence limit = 2.2% to 6.3%), while lean body mass (mean = -0.6%; 95% confidence limit = -1.2% to -0.1%), strength (leg press, mean = -5.6%; 95% confidence limit = -8.3% to -2.8%; chest press, mean = -11.0%; 95% confidence limit = -14.8% to -7.8%), and cognitive function (mean = -3.7%; 95% confidence limit = -5.7% to -1.8%) declined (all P < .05). Interviews revealed key facilitators (social aspects and beliefs about benefits of exercise) and barriers (affordability and general aversion to gyms) to exercise maintenance in this population.

Conclusion: Key barriers and facilitators to exercise maintenance were identified, which will inform the development of future behavior change interventions to support exercise participation and maintenance in older adults to mitigate adverse changes in body composition and physical and cognitive function with advancing age. J Am Geriatr Soc 68:163-169, 2019.
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http://dx.doi.org/10.1111/jgs.16209DOI Listing
January 2020

Prevalence, Magnitude and Methods of Rapid Weight Loss Reported by Male Mixed Martial Arts Athletes in Ireland.

Sports (Basel) 2019 Sep 9;7(9). Epub 2019 Sep 9.

School of Health and Human Performance, Dublin City University, Dublin D09 V209, Ireland.

Rapid weight loss (RWL) is frequently practiced in weight category sports, including Mixed Martial Arts (MMA). The aim of the present study was to describe self-reported methods of RWL in a sample of competitive MMA athletes comprising of both amateur and professional fighters. The previously-validated Rapid Weight Loss Questionnaire, with the addition of questions on water loading and hot salt baths, was completed anonymously online by athletes (n = 30; all male, n = 15/15 professional/amateur) from MMA clubs around Dublin, Ireland. All but one (97%) of the athletes surveyed lost weight in order to compete, with the average weight loss being 7.9% ± 3.1% of habitual body mass. The RWL score (mean ± SD) for this sample was 37.9 ± 9.6, and a tendency for higher [6.0 (95%CI; -1.1, 13.1) ( = 0.093; = 0.64)] RWL scores for professional (40.8 ± 8.9) compared to amateur (34.8 ± 9.6) athletes was observed. Frequencies of "always" or "sometimes" were reported as 90% for water loading, 76% for hot salt baths and 55% for 24 h of fasting. Fellow fighters (41%) and coaches/mentors (38%) were "very influential" on RWL practices of these athletes, with doctors (67%), dietitians (41%), and physical trainers (37%) said to be "not influential". RWL is highly prevalent in MMA across both amateur and professional athletes, and RWL scores are higher than other combat sports. Water loading and hot salt baths are amongst the most commonly used methods of RWL despite little research on these methods for body mass reduction or effects on performance in weight category sports.
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http://dx.doi.org/10.3390/sports7090206DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6783947PMC
September 2019

Maternal obesity trends in a large Irish university hospital.

Eur J Obstet Gynecol Reprod Biol 2019 Jul 10;238:95-99. Epub 2019 May 10.

UCD Centre for Human Reproduction, Coombe Women and Infants University Hospital, Ireland.

Objective(s): This study aimed to examine recent trends in maternal obesity.

Study Design: This retrospective observational study used routinely computerised clinical and sociodemographic data of women who presented for antenatal care in a large maternity hospital in Ireland during the eight years 2010-17. Women with complete body mass index (BMI) data who delivered a baby weighing ≥500 g were included in the study. BMI was based on the measurement of weight and height and was categorised into the World Health Organizations (WHO) classifications.

Results: The number of women delivered was 67,949 and 99.1% had complete data. The overall obesity rate increased from 16.0% (95% CI 15.3-16.8%) in 2010 to 18.9% (95% CI 18.0-19.7%) in 2017 (+18.1%, p < 0.001). This increase occurred in the mild, moderate and severe obesity subcategories (all p < 0.01). Overall, obesity was associated with multiparity, maternal age, maternal birth in Ireland or the United Kingdom (UK), depression, unemployment and unplanned pregnancy. The increase in obesity was more pronounced in nulliparas than in multiparas, particularly nulliparas <30 years. The increased obesity levels were accompanied by major sociodemographic changes in the hospital population from 2010 to 2017 with an increase in the average maternal age from 30.5 years to 32.2 years (p < 0.001) and a decrease in the proportion of nulliparas aged <30 years (from 40.6% to 28.8%, p < 0.001).

Conclusion(s): It is likely that the escalating maternal obesity levels will lead to further increases in obstetric complications and interventions. The escalation was accompanied by major sociodemographic changes which have implications for healthcare planning and public health interventions.
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http://dx.doi.org/10.1016/j.ejogrb.2019.05.003DOI Listing
July 2019

Fetal growth and maternal alcohol consumption during early pregnancy.

Eur J Obstet Gynecol Reprod Biol 2019 May 20;236:148-153. Epub 2019 Feb 20.

UCD Centre for Human Reproduction, Coombe Women and Infants University Hospital, Ireland.

Objective: The relationship between light maternal alcohol consumption and fetal outcome remains contentious and the professional advice women receive is conflicting. The aim of this large epidemiological study was to examine the relationship between fetal growth and maternal alcohol behaviour before and during early pregnancy.

Study Design: Clinical and sociodemographic details of women who delivered a baby weighing ≥500 g during the eight years 2010-18 were analysed. Details on lifestyle behaviour before pregnancy and at the time of the first antenatal hospital visit were computerised using a standardised questionnaire.

Results: Of 68,925 women, 33.6% abstained from alcohol consumption before pregnancy and 98.4% reported they were abstaining at their first antenatal visit. Only 1.2% reported light consumption (1-2 units/week, median 1.0 IQR 1.0), 0.4% reported moderate/heavy consumption (>3 units/week, median 4.0 IQR 4.0) and 0.3% reported binge drinking (>5 units in one sitting, median 3.0 IQR 4.0). Women who consumed alcohol in binges were more likely to be <30years whereas women who consumed alcohol weekly were more likely to be ≥30years. Women who who consumed any alcohol during early pregnancy were more likely to be multiparous, Irish-born, to have an unplanned pregnancy, to be unemployed, on medications for depression or anxiety, current smokers and abusing illicit drugs. In the absence of persistent smoking or illicit drug abuse, there was no relationship between light alcohol consumption during early pregnancy and the subsequent mean birth weight, preterm delivery (%), small-for-gestational age (%) and mean neonatal head circumference.

Conclusion(s): Women who consume alcohol should continue to be advised of the fetal and maternal risks of heavy consumption and, if applicable, of the need to quit smoking and avoid illicit drugs. However, women who have consumed alcohol before realising that they were pregnant or who consumed alcohol in light amounts during early pregnancy, may be reassured that their alcohol consumption did not impact adversely on their baby's growth.
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http://dx.doi.org/10.1016/j.ejogrb.2019.02.005DOI Listing
May 2019

Regulation of GLUT4 translocation in an in vitro cell model using postprandial human serum ex vivo.

Exp Physiol 2019 06 29;104(6):800-807. Epub 2019 Mar 29.

Food for Health Ireland, University College Dublin, Dublin, Ireland.

New Findings: What is the research question? This study used a new experimental model, in which culture medium is conditioned with human serum ex vivo, to investigate nutrient-mediated regulation of GLUT4 translocation in skeletal muscle cells in vitro. What is the main finding and importance? Human serum stimulated GLUT4 translocation, an effect differentially modulated by whether the culture medium was conditioned with serum from fasted subjects or with serum collected after feeding of intact or hydrolysed whey protein. Conditioning cell culture medium with human serum ex vivo represents a new approach to elucidate the effects of ingesting specific nutrients on skeletal muscle cell metabolism.

Abstract: Individual amino acids, amino acid mixtures and protein hydrolysates stimulate glucose uptake in many experimental models. To replicate better in vitro the dynamic postprandial response to feeding in vivo, in the present study we investigated the effects of culture media conditioned with fasted and postprandial human serum on GLUT4 translocation in L6-GLUT4myc myotubes. Serum samples were collected from healthy male participants (n = 8) at baseline (T0), 60 (T60) and 120 min (T120) after the ingestion of 0.33 g (kg body mass) of intact (WPC) or hydrolysed (WPH) whey protein and an isonitrogenous non-essential amino acid (NEAA) control. L6-GLUT4myc myotubes were starved of serum and amino acids for 1 h before incubation for 1 h in medium containing 1% postprandial human serum, after which GLUT4 translocation was determined via colorimetric assay. Medium conditioned with fasted human serum at concentrations of 5-20% increased cell surface GLUT4myc abundance. Incubation with serum collected after the ingestion of WPH increased cell surface GLUT4myc at T60 relative to T0 [mean (lower, upper 95% confidence interval)]; [1.13 (1.05, 1.22)], whereas WPC [0.98 (0.90, 1.07)] or NEAA [1.02 (0.94, 1.11)] did not. The differential increases in cell surface GLUT4myc abundance were not explained by differences in serum concentrations of total, essential and branched-chain amino acids or insulin, glucagon-like peptide 1 (GLP-1) and gastric inhibitory polypeptide (GIP). Using a new ex vivo, in vitro approach, cell culture medium conditioned with postprandial serum after the ingestion of a whey protein hydrolysate increased GLUT4 translocation in skeletal muscle cells.
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http://dx.doi.org/10.1113/EP087356DOI Listing
June 2019

The interaction between maternal smoking, illicit drug use and alcohol consumption associated with neonatal outcomes.

J Public Health (Oxf) 2020 05;42(2):277-284

UCD Centre for Human Reproduction, Coombe Women and Infants University Hospital, Ireland.

Background: The adverse effects of smoking on neonatal outcomes, such as small-for-gestational-age (SGA), has been extensively studied however, the consequences of smoking combined with alcohol and/or drug use is less clear.

Methods: This retrospective observational study analyzed clinical and sociodemographic details of 40156 women who delivered a singleton baby between the years 2011 and 2015.

Results: Compared with women who had never smoked, smokers who did not engage in alcohol or drug use had an odds ratio (OR) of delivering a baby who was SGA of 3.2 (95% CI: 3.1-3.5). Smokers who used illicit drugs in isolation or in combination with alcohol during pregnancy had higher ORs for SGA (1.4, 95% CI: 1.1-1.7, P = 0.006 and 1.8, 95% CI: 1.2-2.7, P = 0.007) compared to women who smoked but did not engage in alcohol or drug use in pregnancy. These women also delivered babies with lower mean birthweights (125 g, P < 0.001 and 181.4 g, P = 0.003) and head circumferences (0.4 cm, P < 0.001 and 0.3 cm, P = 0.048). Women who smoked and used alcohol, but not illicit drugs were not associated adverse outcomes above that of smoking in isolation.

Conclusion: Illicit drug use combined with maternal smoking during pregnancy increases the risk of adverse neonatal outcomes above that of smoking in isolation.
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http://dx.doi.org/10.1093/pubmed/fdz010DOI Listing
May 2020

Anticatabolic Effects of Ketone Bodies in Skeletal Muscle.

Trends Endocrinol Metab 2019 04 31;30(4):227-229. Epub 2019 Jan 31.

National Institute for Cellular Biotechnology, School of Health and Human Performance, Dublin City University, Glasnevin, Dublin 9, Ireland. Electronic address:

The ketone bodies acetoacetate (AcAc) and β-hydroxybutyrate (βHB) are the subject of renewed interest given recently established pleiotropic effects regulating inflammation, oxidative stress, and gene expression. Anticatabolic effects of β-hydroxybutyrate have recently been demonstrated in human skeletal muscle under inflammatory insult, thereby expanding upon the wide-ranging therapeutic applications of nutritional ketosis.
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http://dx.doi.org/10.1016/j.tem.2019.01.006DOI Listing
April 2019

Effect of Heavy Resisted Sled Sprint Training During the Competitive Season on Sprint and Change-of-Direction Performance in Professional Soccer Players.

Int J Sports Physiol Perform 2019 Sep;14(8):1066-1073

Purpose: Resisted sled sprinting (RSS) is an effective tool for improving sprint performance over short distances, but the effect on change-of-direction (COD) performance is largely unknown. The present study investigated the effect of heavy RSS training during the competitive season on sprint and COD performance in professional soccer players.

Methods: Over 6 wk in-season, an RSS training group (n = 6) performed RSS at a sled load of 30% body mass for a total program running distance of 800 m, whereas an unresisted sprint (URS) training group (n = 7) performed the same distance of unresisted sprinting. A 20-m maximal sprint with split times measured at 5, 10, and 20 m and the sprint 9-3-6-3-9 m with 180° turns COD test were performed before and after the intervention.

Results: Sprint performance (mean, 95% confidence limits, qualitative inference) was improved in both groups over 5 m (URS, 5.1%, -2.4 to 12.7, likely moderate; RSS, 5.4%, 0.5-10.4, likely moderate), 10 m (URS, 3.9%, -0.3 to 8.1, very likely moderate; RSS, 5.0%, 1.8-8.0, very likely large), and 20 m (URS, 2.0%, -0.6 to 4.5, likely moderate; RSS, 3.0%, 1.7-4.4, very likely moderate). COD was improved in both groups (URS, 3.7%, 2.2-5.2, most likely large; RSS, 3.3%, 1.6-5.0, most likely moderate). Between-groups differences were unclear.

Conclusion: Heavy RSS and URS training matched for running distance were similarly effective at improving sprint and COD performance in professional soccer players when performed in the competitive phase of the season.
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http://dx.doi.org/10.1123/ijspp.2018-0592DOI Listing
September 2019

The effects of a combined bodyweight-based and elastic bands resistance training, with or without protein supplementation, on muscle mass, signaling and heat shock response in healthy older people.

Exp Gerontol 2019 01 5;115:104-113. Epub 2018 Dec 5.

Institute for Sport & Health, School of Public Health, Physiotherapy and Sports Science, University College Dublin, Ireland; Food for Health Ireland, University College Dublin, Ireland. Electronic address:

This investigation sought to determine the effects of twelve weeks of resistance exercise training in addition to protein supplementation on body composition, markers of muscle atrophy/hypertrophy and heat shock response (HSR) in healthy older adults. Thirty-eight healthy sedentary participants (M/F, 18/20; age, 63.5 ± 4.4 y) were randomly assigned to four groups: I) PLACEBO: no training, receiving placebo sachets; II) NUTRITION: no training, receiving protein supplementation sachets; III) EXERCISE PLACEBO: training, placebo sachets and IV) EXERCISE NUTRITION: training, receiving protein sachets. The resistance training (using bodyweight and elastic bands) consisted of 45 min supervised training sessions, 3×/week. Participants from both exercise groups increased their total lean body mass (from 48.4 ± 8.7 to 49.2 ± 8.7 kg and from 44.9 ± 7.8 to 45.9 ± 8.1 kg, average of gain ~0.8 and 1 kg, placebo and nutrition respectively) and improved results in physical tests. Exercise nutrition group also reduced their body fat (from 34.8 ± 7.3 to 32.9 ± 7.4%), increased the expression of proteins/gene involved on the HSR, S6 and eEF2, while FOXO3 and Murf1 were reduced. Expression of MHC-I was reduced in both exercise groups while MHC-IIa increased, with no effect of protein supplementation alone. Body-weight and elastic bands based resistance exercise prompted, in healthy older people, improvements in body composition and muscle function. When protein supplementation was added to the people engaged in resistance training, improvements in fat mass and changes in skeletal muscle signaling were detected, favoring protein synthesis pathways and the protective heat shock response.
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http://dx.doi.org/10.1016/j.exger.2018.12.004DOI Listing
January 2019

The implications of high carbon monoxide levels in early pregnancy for neonatal outcomes.

Eur J Obstet Gynecol Reprod Biol 2019 Feb 30;233:6-11. Epub 2018 Nov 30.

The UCD Centre for Human Reproduction, Coombe Women and Infants University Hospital, Ireland.

Objectives: The aim of this study was to examine the implications of increased maternal Breath Carbon Monoxide (BCO) levels at the first antenatal visit for subsequent birthweight (BW) and neonatal outcomes.

Study Design: Secondary analysis of a prospective, observational study. Pregnant women aged ≥18years who understood English were recruited (n=250). However, only women who delivered a normally formed baby weighing ≥500g were analysed (n=234). At the first antenatal visit, a research questionnaire was completed and a BCO test was performed. Obstetric and neonatal data computerised by midwives at the first antenatal visit and updated after delivery were also analysed.

Results: Results from the receiver operating characteristic (ROC) curve indicated the highest combined sensitivity and specificity for smoking was observed at a BCO cut-off level of 3ppm (sensitivity 85%, specificity 90%). Of the 234 women, 53 (22.6%) had a BCO ≥3ppm but only 36 (15.4%) disclosed smoking to the midwife on routine questioning. A further 23 (9.8%) were classified as non-disclosers based on a research questionnaire and/or a BCO measurement ≥3ppm. No relationship was found between the self-reported number of cigarettes daily in early pregnancy and BW (r=0.05, p=0.78). However, an inverse relationship was found between maternal BCO levels and BW (r=-0.31, p<0.001). BCO levels ≥3ppm in early pregnancy were associated with an increased risk of emergency caesarean section, low birth weight, BW <25th centile, fetal distress and having two or more adverse pregnancy events (all p<0.05). Smoking non-disclosers had babies with decreased BWs (-400.1g, 95% CI 141.1-659.0g, p<0.001), and higher rates of BW <25th centile (56.5% versus 25.3%, p<0.001), small-for-gestational-age (21.7% versus 9.1%, p<0.001) and fetal distress (39.1% versus 16.0%, p<0.01) compared to non-smokers Non-disclosers at the first antenatal visit also had a 22% higher rate of having two or more adverse pregnancy events (p<0.05).

Conclusion: The results showed that an increased BCO level was associated with a lower BW and increased risk of adverse pregnancy and neonatal outcomes. This strengthens the case for universal BCO screening at the first antenatal visit. A high BCO reading should be an indication for referral to stop smoking services referral and close fetal surveillance.
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http://dx.doi.org/10.1016/j.ejogrb.2018.11.020DOI Listing
February 2019
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