International Journal of Sport Nutrition and Exercise Metabolism

This study investigated the effect of oral and topical sodium bicarbonate (SB) on soccer-specific performance during simulated soccer exercise. In a block randomized, double-blind, crossover design, 10 collegiate male soccer players (stature: 181.7 ± 3.2 cm, body mass: 81.7 ± 10.5 kg) performed soccer-specific performance tests (countermovement jumps, Illinois agility, 8 × 25 m repeated sprints) throughout a 90-min soccer-specific aerobic field test (SAFT90) following 0.3 g/kg body mass SB in capsules (SB-ORAL), 0...

PURPOSE: This study investigated the effect of menthol (MEN) mouth rinsing (MR) on cycling performance during a modified variable cycle test (M-VCT) in adolescent athletes under hot conditions (31.4 ± 0.9 °C, 23.4 ± 3.7% relative humidity). METHODS: Trained adolescent male cyclists (n = 11, 16.7 ± 1.3 years, height 176.6 ± 8.8 cm, body mass 65.8 ± 11.6 kg, maximal oxygen uptake 62.97 ± 7.47 ml·kg-1·min-1) voluntarily completed three trials (familiarization and two experimental) of a 30-min M-VCT, which included five 6-min laps consisting of three 6-s accelerations and three 10-s sprints throughout each lap...

This study aimed to determine energy availability (EA) and within-day energy balance (WDEB) in female soccer players during preseason and also explored eating disorder risk and athlete food choice. We hypothesized commonly used indicators of low energy availability (LEA) risk would correlate with measured EA and WDEB variables, and that food choice determinants would differ according to EA. Eleven National Premier League female soccer players participated in this observational cross-sectional study over 3 weeks...

No abstract text is available yet for this article.

This study aimed to investigate the effects of caffeine ingestion by chewing gum (GUMCAF) combined with priming exercise on pulmonary oxygen uptake (V˙O2) and near-infrared spectroscopy-derived muscle oxygen extraction (HHb + Mb) kinetics during cycling performed in a severe-intensity domain. Fifteen trained cyclists completed four visits: two under a placebo gum (GUMPLA) and two under GUMCAF ingestion. Each visit consisted of two square-wave cycling bouts at Δ70 intensity (70% of difference between the V˙O2 at first ventilatory threshold and V˙O2max) with duration of 6 min each and 5 min of passive rest between the bouts...

OBJECTIVE: Micronutrient status, specifically vitamin D and iron, represent modifiable factors for optimizing military readiness. The primary purpose of this investigation was to determine associations between micronutrient deficiency (i.e., iron status and 25-hydroxy-vitamin D [25(OH)D]) and operationally relevant outcomes (i.e., skeletal health, musculoskeletal injury) at baseline and post-10 weeks of arduous military training. METHODS: A total of 227 (177 men, 50 women) Marine Officer Candidates School (OCS) candidates who completed OCS training with complete data sets were included in this analysis...

BACKGROUND: Several studies have revealed the positive healthy impacts of branched-chain fatty acids (BCFAs). However, most of these studies evaluated the serum BCFAs in humans, or treatment with exogenous BCFAs in animal or in-vitro models and the health impacts of dietary BCFAs have not yet been studied. Due to positive effects of BCFAs in sport, in the current study, we aimed to investigate the association between dietary BCFAs and metabolic and inflammatory parameters among elite and subelite soccer players...

OBJECTIVES: Dietary strategies to improve arachidonic acid:eicosapentaenoic acid (AA:EPA) ratios are of interest due to potential reductions in inflammation and oxidative stress following exercise. The aim of this study was to investigate the impact of a novel dietary intervention, that is, the ingestion of 30 g of dark chocolate, on blood lipid profiles and gut microbiota composition in elite male soccer players. METHODS: Professional male soccer players were randomly assigned to the experimental group (DC) provided with 30 g of dark chocolate or to the control group (WC), provided with 30 g of white chocolate, for 30 days...

No abstract text is available yet for this article.

Beta-alanine is a nonessential amino acid that is commonly used to improve exercise performance. It could influence the buffering of hydrogen ions produced during intense exercise and delay fatigue, providing a substrate for increased synthesis of intramuscular carnosine. This systematic review evaluates the effects of beta-alanine supplementation on maximal intensity exercise in trained, young, male individuals. Six databases were searched on August 10, 2023, to identify randomized, double-blinded, placebo-controlled trials investigating the effect of chronic beta-alanine supplementation in trained male individuals with an age range of 18-40 years...

A comprehensive recent study by Trommelen et al. demonstrated that muscle tissue exhibits a greater capacity to incorporate exogenous exogenous protein-derived amino acids into bound muscle protein than was previously appreciated, at least when measured in "anabolically sensitive," recreationally active (but not resistance-trained), young men following resistance exercise. Moreover, this study demonstrated that the duration of the postprandial period is modulated by the dose of ingested protein contained within a meal, that is, the postexercise muscle protein synthesis response to protein ingestion was more prolonged in 100PRO than 25PRO...

It is important for athlete and public health that we continue to develop our understanding of the effects of exercise and nutrition on bone health. Bone turnover markers (BTMs) offer an opportunity to accelerate the progression of bone research by revealing a bone response to exercise and nutrition stimuli far more rapidly than current bone imaging techniques. However, the association between short-term change in the concentration of BTMs and long-term bone health remains ambiguous. Several other limitations also complicate the translation of acute BTM data to applied practice...

This study aimed to determine whether caffeine gum influenced perceptual-cognitive and physical performance during the extra-time period of simulated soccer match-play. Semiprofessional male soccer players (n = 12, age: 22 ± 3 years, stature: 1.78 ± 0.06 m, mass: 75 ± 9 kg) performed 120-min soccer-specific exercise on two occasions. In a triple-blind, randomized, crossover design, players chewed caffeinated (200 mg; caffeine) or control (0 mg; placebo) gum for 5 min following 90 min of soccer-specific exercise...

No abstract text is available yet for this article.

No abstract text is available yet for this article.

No abstract text is available yet for this article.

Dyslipidemia is a major contributor to the development of atherosclerotic cardiovascular disease. Despite high level of physical activity, athletes are not immune from dyslipidemia, but longitudinal data on the variation of lipids are currently lacking. We sought to assess lipid profile changes over time in Olympic athletes practicing different sports disciplines (power, skills, endurance, and mixed). We enrolled 957 consecutive athletes evaluated from London 2012 to Beijing 2022 Olympic Games. Dyslipidemia was defined as low-density lipoprotein (LDL) ≥115 mg/dl, high-density lipoprotein (HDL) <40 mg/dl for males, or HDL <50 mg/dl for females...

The main objective of this placebo-controlled, triple-blind, balanced crossover study was to assess the acute effects of phenylcapsaicin (PC) intake (2.5 mg) on intraocular pressure (IOP), ocular perfusion pressure (OPP), and heart rate (HR) during a 30-min cycling task performed at 15% of the individual maximal power. Twenty-two healthy young adults performed the cycling task 45 min after ingesting PC or placebo. IOP was measured with a rebound tonometer before exercise, during cycling (every 6 min), and after 5 and 10 min of recovery...

Despite the increased popularity of female elite road cycling, research to inform the fueling requirements of these endurance athletes is lacking. In this case study, we report for the first time the energetics of a female world-tour cyclist competing in the 2023 Tour de France Femmes, an 8-day race of the Union Cycliste Internationale. The 29-year-old athlete presented with oligomenorrhea and low T3 before the race. Total daily energy expenditure assessed with the doubly labeled water technique was 7,572 kcal/day (∼4...

Postexercise hydration is fundamental to replace fluid loss from sweat. This study evaluated rehydration and gastrointestinal (GI) symptoms for each of three beverages: water (W), sports drink (SD), and skimmed, lactose-free milk (SLM) after moderate-intensity cycling in the heat. Sixteen college students completed three exercise sessions each to lose ≈2% of their body mass. They drank 150% of body mass loss of the drink assigned in randomized order; net fluid balance, diuresis, and GI symptoms were measured and followed up for 3 hr after completion of fluid intake...