J Int Soc Sports Nutr
December 2024
Purpose: Han et al. (J Int Soc Sports Nutr 16:55, 2019) sought to quantify the effects of vitamin D supplementation on strength outcomes among athletes in a meta-analysis. The authors reported a pooled effect size (standardized mean difference; SMD) of -0.
View Article and Find Full Text PDFMost resistance training research focuses on inference from average intervention effects from observed group-level change scores (i.e., mean change of group A vs group B).
View Article and Find Full Text PDFThe purpose of this study was to examine the effects of intermittent versus continuous energy restriction on body composition, resting metabolic rate, and eating behaviors in resistance-trained females. Thirty-eight resistance-trained females (mean ± standard deviation age: 22.3 ± 4.
View Article and Find Full Text PDFBackground And Objective: This systematic review with meta-analysis investigated the influence of resistance training proximity-to-failure on muscle hypertrophy.
Methods: Literature searches in the PubMed, SCOPUS and SPORTDiscus databases identified a total of 15 studies that measured muscle hypertrophy (in healthy adults of any age and resistance training experience) and compared resistance training performed to: (A) momentary muscular failure versus non-failure; (B) set failure (defined as anything other than momentary muscular failure) versus non-failure; or (C) different velocity loss thresholds.
Results: There was a trivial advantage for resistance training performed to set failure versus non-failure for muscle hypertrophy in studies applying any definition of set failure [effect size=0.
This study evaluated the influence of acute water ingestion and maintaining an upright posture on raw bioimpedance and subsequent estimates of body fluids and composition. Twenty healthy adults participated in a randomized crossover study. In both conditions, an overnight food and fluid fast was followed by an initial multi-frequency bioimpedance assessment (InBody 770).
View Article and Find Full Text PDFLewis, MH, Siedler, MR, Lamadrid, P, Ford, S, Smith, T, SanFilippo, G, Waddell, B, Trexler, ET, Buckner, S, and Campbell, BI. Sex differences may exist for performance fatigue but not recovery after single-joint upper-body and lower-body resistance exercise. J Strength Cond Res 36(6): 1498-1505, 2022-This study evaluated sex differences in performance recovery and fatigue during dynamic exercise.
View Article and Find Full Text PDFAs a nitric oxide (NO) enhancer, citrulline malate (CM) has recently been touted as a potential ergogenic aid to both resistance and high-intensity exercise performance, as well as the recovery of muscular performance. The mechanism has been associated with enhanced blood flow to active musculature, however, it might be more far-reaching as either ammonia homeostasis could be improved, or ATP production could be increased via greater availability of malate. Moreover, CM might improve muscle recovery via increased nutrient delivery and/or removal of waste products.
View Article and Find Full Text PDFBodybuilders are judged on the subjective visual assessment of their muscular size, proportion, and leanness. This case series tracked four drug-free bodybuilders (3 male) during the off-season, pre-competition and recovery phases. This study aimed to comprehensively profile key biopsychosocial changes occurring pre/post competition in a group of British natural bodybuilders.
View Article and Find Full Text PDFThe purpose of this case-series was to evaluate the physiological, psychological and performance-related changes that occur during the postcompetition period. Participants included three male (34.3 ± 6.
View Article and Find Full Text PDFFollowing critical evaluation of the available literature to date, The International Society of Sports Nutrition (ISSN) position regarding caffeine intake is as follows: 1. Supplementation with caffeine has been shown to acutely enhance various aspects of exercise performance in many but not all studies. Small to moderate benefits of caffeine use include, but are not limited to: muscular endurance, movement velocity and muscular strength, sprinting, jumping, and throwing performance, as well as a wide range of aerobic and anaerobic sport-specific actions.
View Article and Find Full Text PDFBackground & Aims: It is recommended that patients consume at least 60 g of dietary protein per day to attenuate loss of fat-free mass (FFM) following bariatric surgery. To date, research on the effectiveness and tolerability of protein supplementation in bariatric patients is limited. The purpose of the current study was to determine if provision of 12-weeks of daily protein supplementation was an effective and tolerable method of facilitating higher protein intakes in bariatric surgery patients.
View Article and Find Full Text PDFSchoenfeld, BJ, Alto, A, Grgic, J, Tinsley, G, Haun, CT, Campbell, BI, Escalante, G, Sonmez, GT, Cote, G, Francis, A, and Trexler, ET. Alterations in body composition, resting metabolic rate, muscular strength, and eating behavior in response to natural bodybuilding competition preparation: A case study. J Strength Cond Res 34(11): 3124-3138, 2020-We carried out a prospective case study in a high-level amateur natural male bodybuilder throughout preparation for 4 competitions and during the ensuing postcontest recovery period.
View Article and Find Full Text PDFThe purpose of the present study was to examine the acute effects of an herbal supplement containing a 70:30 blend of Rhaponticum carthamoides extract and Rhodiola rosea extract, respectively, on performance fatigability and the affective responses prior to and following exercise. Thirty men (age = 22.3 ± 4.
View Article and Find Full Text PDFThe popularity of physique sports is increasing, yet there are currently few comprehensive nutritional guidelines for these athletes. Physique sport now encompasses more than just a short phase before competition and offseason guidelines have recently been published. Therefore, the goal of this review is to provide an extensive guide for male and female physique athletes in the contest preparation and recovery period.
View Article and Find Full Text PDFGonzalez, AM and Trexler, ET. Effects of citrulline supplementation on exercise performance in humans: A review of the current literature. J Strength Cond Res 34(5): 1480-1495, 2020-L-citrulline, a nonessential amino acid found primarily in watermelon, has recently garnered much attention for its potential to augment L-arginine bioavailability, nitric oxide production, and exercise performance.
View Article and Find Full Text PDFThis study examined the acute and resting changes of brain-derived neurotrophic factor (BDNF) and inteleukin-6 (IL-6) and if changes in these biomarkers were correlated during resistance training (RT). Fifteen men with ≥2 years of RT experience (age: 23 ± 3 years, body mass: 84.4 ± 12.
View Article and Find Full Text PDFThe ergogenic effects of citrulline malate (CitMal) and beetroot juice (BEET) have been widely studied, but their effects on physiological outcomes related to resistance exercise are not fully understood. The purpose of this randomized, double-blind, crossover study was to investigate the effects of CitMal (8 g) and BEET (400 mg nitrate) on blood pressure (BP), blood flow, and energy efficiency during submaximal leg extension. Recreationally active males ( = 27; age: 22 ± 4 yrs) completed familiarization, followed by three testing visits.
View Article and Find Full Text PDFClin Physiol Funct Imaging
November 2019
Objectives: To create normative data for visceral adipose tissue (VAT) derived from the GE Lunar iDXA specific to sex and age cohorts for adults in the United States (US).
Methods: A cross-sectional analysis of 649 adults were evaluated [Mean ± SD (Range): Males: n = 351; Age = 33·2 ± 17·4 years (18-75 years); Body mass index (BMI) = 26·5 ± 5·4 kg·m (17·5-44·2 kg·m ); Females: n = 298; Age = 28·5 ± 14·3 years (18·0-75·0 years); BMI=25·8 ± 6·9 kg·m (17·9-54·8 kg·m )]. From a total body dual-energy X-ray absorptiometry (DXA) scan, VAT mass (kg) and volume (cm ) were quantified from the software-delineated region-of-interest.
Trexler, ET, Keith, DS, Schwartz, TA, Ryan, ED, Stoner, L, Persky, AM, and Smith-Ryan, AE. Effects of citrulline malate and beetroot juice supplementation on blood flow, energy metabolism, and performance during maximum effort leg extension exercise. J Strength Cond Res 33(9): 2321-2329, 2019-Citrulline malate (CitMal) and beetroot juice (BEET) are increasingly popular ergogenic aids, but few studies have rigorously investigated their effects on resistance exercise performance and underlying mechanisms.
View Article and Find Full Text PDFThe purpose of this paper was to determine the effect of replacing breakfast with a high-fat drink on fat mass (FM), lean mass (LM), percent body fat (%BF), visceral fat (VAT), resting metabolic rate (RMR), fuel utilization (RER), blood lipids and satiety in overweight and obese adults. Healthy adults ( = 42; 21 Females; body mass index (BMI): 32.8 ± 4.
View Article and Find Full Text PDFBackground: Citrulline is an increasingly common dietary supplement that is thought to enhance exercise performance by increasing nitric oxide production. In the last 5 years, several studies have investigated the effects of citrulline supplements on strength and power outcomes, with mixed results reported. To date, the current authors are unaware of any attempts to systematically review this emerging body of literature.
View Article and Find Full Text PDFThe purpose of this study was to establish normative fat-free mass index (FFMI) ranges in collegiate female athletes. A sample of 266 female athletes (Mean±SD; Age: 19.7 ± 1.
View Article and Find Full Text PDFIncreased blood flow via vasodilation, metabolite production, and venous pooling contribute to the hyperemia and cellular swelling experienced during resistance training. It has been suggested that these effects play a role in hypertrophic adaptations. Over the past 2 decades, sport supplement products have been marketed to promote exercise hyperemia and intracellular fluid storage, thereby enhancing hypertrophy via acute swelling of myocytes.
View Article and Find Full Text PDFThis study sought to investigate the effects of a multistrain probiotic on body composition, regional adiposity, and a series of associated metabolic health outcomes. Female health care workers employed on a rotating-shift schedule ( = 41) completed baseline anthropometric assessments; a fasted blood draw; questionnaires to assess anxiety, depression (Hospital Anxiety and Depression Scale), and fatigue (Chalder Fatigue Survey); and an exercise fatigue test. Identical post-tests occurred following 6 weeks of daily supplementation with placebo (PLA) or probiotics (2.
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