Explore the vast range of titles available.

Based on a comprehensive review and critical analysis of the literature regarding the nutritional concerns of female athletes, conducted by experts in the field and selected members of the International Society of Sports Nutrition (ISSN), the following conclusions represent the official Position of the Society: 1. Female athletes have unique and unpredictable hormone profiles, which influence their physiology and nutritional needs across their lifespan. To understand how perturbations in these hormones affect the individual, we recommend that female athletes of reproductive age should track their hormonal status (natural, hormone driven) against training and recovery to determine their individual patterns and needs and peri and post-menopausal athletes should track against training and recovery metrics to determine the individuals' unique patterns. 2. The primary nutritional consideration for all athletes, and in particular, female athletes, should be achieving adequate energy intake to meet their energy requirements and to achieve an optimal energy availability (EA); with a focus on the timing of meals in relation to exercise to improve training adaptations, performance, and athlete health. 3. Significant sex differences and sex hormone influences on carbohydrate and lipid metabolism are apparent, therefore we recommend first ensuring athletes meet their carbohydrate needs across all phases of the menstrual cycle. Secondly, tailoring carbohydrate intake to hormonal status with an emphasis on greater carbohydrate intake and availability during the active pill weeks of oral contraceptive users and during the luteal phase of the menstrual cycle where there is a greater effect of sex hormone suppression on gluconogenesis output during exercise. 4. Based upon the limited research available, we recommend that pre-menopausal, eumenorrheic, and oral contraceptives using female athletes should aim to consume a source of high-quality protein as close to beginning and/or after completion of exercise as possible to reduce exercise-induced amino acid oxidative losses and initiate muscle protein remodeling and repair at a dose of 0.32-0.38 g·kg . For eumenorrheic women, ingestion during the luteal phase should aim for the upper end of the range due to the catabolic actions of progesterone and greater need for amino acids. 5. Close to the beginning and/or after completion of exercise, peri- and post-menopausal athletes should aim for a bolus of high EAA-containing (~10 g) intact protein sources or supplements to overcome anabolic resistance. 6. Daily protein intake should fall within the mid- to upper ranges of current sport nutrition guidelines (1.4-2.2 g·kg ·day ) for women at all stages of menstrual function (pre-, peri-, post-menopausal, and contraceptive users) with protein doses evenly distributed, every 3-4 h, across the day. Eumenorrheic athletes in the luteal phase and peri/post-menopausal athletes, regardless of sport, should aim for the upper end of the range. 7. Female sex hormones affect fluid dynamics and electrolyte handling. A greater predisposition to hyponatremia occurs in times of elevated progesterone, and in menopausal women, who are slower to excrete water. Additionally, females have less absolute and relative fluid available to lose via sweating than males, making the physiological consequences of fluid loss more severe, particularly in the luteal phase. 8. Evidence for sex-specific supplementation is lacking due to the paucity of female-specific research and any differential effects in females. Caffeine, iron, and creatine have the most evidence for use in females. Both iron and creatine are highly efficacious for female athletes. Creatine supplementation of 3 to 5 g per day is recommended for the mechanistic support of creatine supplementation with regard to muscle protein kinetics, growth factors, satellite cells, myogenic transcription factors, glycogen and calcium regulation, oxidative stress, and inflammation. Post-menopausal females benefit from bone health, mental health, and skeletal muscle size and function when consuming higher doses of creatine (0.3 g·kg ·d ). 9. To foster and promote high-quality research investigations involving female athletes, researchers are first encouraged to stop excluding females unless the primary endpoints are directly influenced by sex-specific mechanisms. In all investigative scenarios, researchers across the globe are encouraged to inquire and report upon more detailed information surrounding the athlete's hormonal status, including menstrual status (days since menses, length of period, duration of cycle, etc.) and/or hormonal contraceptive details and/or menopausal status.

Context: Previous researchers have indicated the importance of body composition and muscle quality in athletic performance. However, body composition and muscle-quality measures in swimmers and divers over a training season have yet to be evaluated. Objective: To identify changes in body composition and muscle characteristics over a competitive season and identify relationships between these variables and performance in National Collegiate Athletic Association Division I swimmers and divers. Design: Cross-sectional study. Setting: University laboratory. Patients or Other Participants: A total of 17 collegiate swimmers and divers (age = 18.6 ± 0.7 years, height = 175.8 ± 4.0 cm, body mass = 69.7 ± 7.0 kg). Main Outcome Measure(s): At preseason and postseason, body composition in each participant was assessed using dual-energy x-ray absorptiometry. Echo intensity and muscle cross-sectional area were determined from an ultrasound panoramic scan of the vastus lateralis muscle. Race times were obtained from the university athletic Web site. Results: Lean mass (P = .016), arm lean mass (P = .008), and muscle cross-sectional area (P = .03) were higher at postseason, whereas body fat percentage (P = .041) and echo intensity (P = .0007) were lower at postseason. Performance improved from preseason to postseason in all event groups (sprinters, distance swimmers, and divers; P < .05). Conclusions: Body composition and muscle characteristics improved through 1 training season, which may have implications for performance. Quantifying body composition and muscle characteristics may be beneficial for professionals who work with athletes in order to improve performance and prevent injury.

Nutritional status is a strong predictor of postoperative outcomes and is recognized as an important component of surgical recovery programs. Adequate nutritional consumption is essential for addressing the surgical stress response and mitigating the loss of muscle mass, strength, and functionality. Especially in older patients, inadequate protein can lead to significant muscle atrophy, leading to a loss of independence and increased mortality risk. Current nutritional recommendations for surgery primarily focus on screening and prevention of malnutrition, pre-surgical fasting protocols, and combating post-surgical insulin resistance, while recommendations regarding macronutrient composition and timing around surgery are less established. The goal of this review is to highlight oral nutrition strategies that can be implemented leading up to and following major surgery to minimize atrophy and the resultant loss of functionality. The role of carbohydrate and especially protein/essential amino acids in combating the surgical stress cascade and supporting recovery are discussed. Practical considerations for nutrient timing to maximize oral nutritional intake, especially during the immediate pre- and post- surgical periods, are also be discussed.

Age-related anabolic resistance can lead to reduced muscle mass but can be costly and timely to diagnose. Multi-frequency bioelectrical impedance analysis could potentially be used as a non-invasive tool for the assessment of anabolic resistance as changes in frequency-dependent impedance values may reflect fluid shifts occurring with nutrient uptake. This exploratory pilot study evaluated the effects of acute essential amino acid (EAA) intake on raw bioimpedance and fluid shifts in healthy young adults (YA, n=5) and older adults (OA, n=7). Participants completed a five-hour protocol with multifrequency bioelectrical impedance analysis (MF-BIA) at baseline and every 30 minutes post-consumption of a 10 g EAA beverage. Whole-body and segmental values for impedance (Z), resistance (R), reactance (Xc), phase angle (PhA), and body water compartments were assessed. YA demonstrated significantly higher Z, R, Xc, and PhA values compared to OA (p<0.05), particularly in the leg segments and at 50 kHz. Time effects revealed declines in R (p=0.013) and Xc (p=0.002) following EAA ingestion, consistent with postprandial fluid shifts. Fluid analysis showed significant group differences only for ECW/ICW ratio (p=0.001-0.004) with OA > YA and increases in TBW, ICW, and ECW over time. Raw bioimpedance values distinguished between age groups and reflected acute responses to nutrient intake. These findings suggest MF-BIA may be sensitive to short-term physiological changes and, with further validation, could support assessments of muscle quality and nutritional responsiveness.

Normal weight obesity (NWO) describes individuals who have a normal weight body mass index (BMI), but have an unhealthy amount of body fat. Based on the life-long habits that develop during college, exploring NWO among a college-aged population may be essential in identifying and preventing obesity that develops in early adulthood. This study aimed to characterize NWO among young adults with normal weight BMI. 94 college students (Mean ± SD: Age: 19.6 ± 1.5 yrs; BMI: 21.9 ± 1.8 kg/m ) enrolled during the Fall semester (Aug-Oct) were assessed for body composition by dual energy X-ray absorptiometry to determine body fat percentage, fat mass, lean mass and trunk fat; lifestyle habits were characterized from validated questionnaires. Mean arterial pressure and metabolic biomarkers [total cholesterol, high density lipoproteins, non-high density lipoproteins, and glucose] were evaluated for cardiometabolic health. NWO was defined using data from the National Health and Nutrition Examination Survey (NHANES) for body fat percentage. Data was analyzed by group (NWO vs NWL) and sex. with independent t-tests to investigate continuous data, and chi-square test of independence for categorical data. Rates of NWO for the total sample were 13.8%. Males (n=30) had a higher rate of NWO (26.7%) compared to females (n=64; 7.8%). NWO individuals had higher fat mass (p=0.024), trunk fat (p<0.001), and larger waist to hip ratio (p<0.001) than normal weight lean. NWO also engaged in less vigorous physical activity (p=0.043). The occurrence of NWO among otherwise healthy college students is evident. Identification of these individuals may be an effective component for obesity prevention and treatment. Determining feasible methods to measure body fat in this population is essential, as BMI may mask obesity in a young adult population.

OBJECTIVES/GOALS: We endeavor to investigated the hypothesis that muscle protein synthesis (MPS) is stimulated more after consumption of a 4-ounce beef patty as compared to 4- and 8-ounces of a soy protein based meat alternative (SPBMA) and if a greater stimulation is related to differences in the responses of plasma essential amino acid (EAA) concentrations. METHODS/STUDY POPULATION: Participants were aged 18 to 40 years of age with a BMI between 20 and 32 kg/m2. Written informed consent was obtained from all participants, and approved by UAMS IRB. Participants were assigned to one of three intervention groups via a single-blinded permuted block randomization, stratified for sex: 4 oz beef patty; 4 oz SPBMA; 2 x 4 oz (8oz) SPBMA. The impossible burgerTM was selected as it is primarily soy protein, a high-quality plant protein, and specifically designed to mimic a beef burger. Stable isotope were infused to assess protein metabolism. Appropriate muscle and blood samples were obtained. Enrichment and plasma EAA concentrations were measured with mass spectrometry. ANOVA’s on the change from basal to postprandial were used to identify group difference, significance was accepted at p < 0.05. RESULTS/ANTICIPATED RESULTS: The MPS increase from basal to postprandial indicated a significant main effect of group (p = 0.026), with the beef group (0.020 ± 0.016%/hour) being significantly greater than the 4oz SPBMA (0.003 ± 0.010%/hour; p = 0.021) but not the 8oz PBMA group (0.013 ± 0.016%/hour; p = 0.454). Similar results were observed for whole-body protein synthesis, where the beef group (p = 0.042) and 8oz SPBMA (p = 0.033) were significantly greater than the 4oz SPBMA (p = 0.021). Whole-body protein balance was significantly greater in the 8oz SPBMA as compared to 4oz of beef and SPBMA. Lastly, we observed a significantly relationship (p = 0.046; r = 0.411) between the maximal plasma EAA concentration and change in MPS, indicating the greater rate of MPS following 4oz of beef is mediated by an higher increase in plasma EAA concentrations. DISCUSSION/SIGNIFICANCE: In conclusion, 4oz of beef stimulates muscle protein FSR more than 4oz of a SPBMA. A common SPBMA can stimulate increase in protein metabolism, however, greater amounts are required as compared to beef protein. Further, the change in the muscle protein FSR response was significantly correlated with the maximal EAA concentration.

Ingesting protein-containing supplements and foods provides essential amino acids (EAA) necessary to increase muscle and whole-body protein synthesis (WBPS). Large variations exist in the EAA composition of supplements and foods, ranging from free-form amino acids to whole protein foods. We sought to investigate how changes in peripheral EAA after ingesting various protein and free amino acid formats altered muscle and whole-body protein synthesis. Data were compiled from four previous studies that used primed, constant infusions of L-(ring-2H5)-phenylalanine and L-(3,3-2H2)-tyrosine to determine fractional synthetic rate of muscle protein (FSR), WBPS, and circulating EAA concentrations. Stepwise regression indicated that max EAA concentration (EAACmax; R2 = 0.524, p < 0.001), EAACmax (R2 = 0.341, p < 0.001), and change in EAA concentration (ΔEAA; R = 0.345, p < 0.001) were the strongest predictors for postprandial FSR, Δ (change from post absorptive to postprandial) FSR, and ΔWBPS, respectively. Within our dataset, the stepwise regression equation indicated that a 100% increase in peripheral EAA concentrations increases FSR by ~34%. Further, we observed significant (p < 0.05) positive (R = 0.420–0.724) correlations between the plasma EAA area under the curve above baseline, EAACmax, ΔEAA, and rate to EAACmax to postprandial FSR, ΔFSR, and ΔWBPS. Taken together our results indicate that across a large variety of EAA/protein-containing formats and food, large increases in peripheral EAA concentrations are required to drive a robust increase in muscle and whole-body protein synthesis.

Nutritional interventions are not commonly a standard of care in rehabilitation interventions. A nutritional approach has the potential to be a low-cost, high-volume strategy that complements the existing standard of care. In this commentary, our aim is to provide an evidence-based, practical guide for athletes with injuries treated surgically or conservatively, along with healing and rehabilitation considerations. Injuries are a normal and expected part of exercise participation. Regardless of severity, an injury typically results in the athlete's short- or long-term removal from participation. Nutritional interventions may augment the recovery process and support optimal healing; therefore, incorporating nutritional strategies is important at each stage of the healing process. Preoperative nutrition and nutritional demands during rehabilitation are key factors to consider. The physiological response to wounds, immobilization, and traumatic brain injuries may be improved by optimizing macronutrient composition, caloric consumption, and nutrient timing and using select dietary supplements. Previous research supports practical nutrition recommendations to reduce surgical complications, minimize deficits after immobilization, and maximize the chance of safe return to play. These recommendations include identifying the individual's caloric requirements to ensure that energy needs are being met. A higher protein intake, with special attention to evenly distributed consumption throughout the day, will help to minimize loss of muscle and strength during immobilization. Dietary-supplement strategies may be useful when navigating the challenges of appropriate caloric intake and timing and a reduced appetite. The rehabilitation process also requires a strong nutritional plan to enhance recovery from injury. Athletic trainers, physical therapists, and other health care professionals should provide basic nutritional recommendations during rehabilitation, discuss the timing of meals with respect to therapy, and refer the patient to a registered dietitian if warranted. Because nutrition plays an essential role in injury recovery and rehabilitation, nutritional interventions should become a component of standard-of-care practice after injury. In this article, we address best practices for implementing nutritional strategies among patients with athletic injuries.

The purpose of this trial was to assess the feasibility, acceptability and safety of a 10-week hybrid (in-clinic and virtual) resistance exercise training RET program with or without CrM in individuals treated for colorectal cancer. Twenty-seven participants were randomized to RET plus 5 grams/day of CrM (EXSUPP; n = 13) or 5 grams/day corn-starch maltodextrin placebo (EXPLA; n = 14). RET was performed three times per week. Feasibility was assessed through recruitment, retention and fidelity (percentage of prescribed RET and supplementation completed). Acceptability was evaluated using a 5-point Likert scale, and safety was monitored through adverse event reporting. Secondary outcomes (body composition, muscular strength, physical function) were assessed pre- and post-intervention using baseline-adjusted ANCOVA models and focus group interviews. Registry-based recruitment identified 1378 potentially eligible individuals and 27 of 410 assessed (6.6%) enrolled, highlighting recruitment challenges. Retention was high (24/27; 88.9%). Adherence to RET and supplementation was strong (both > 85%) with no serious adverse events reported. Participants reported high acceptability for both in person and virtual components. No significant between group differences were observed for secondary outcomes; however, both groups demonstrated modest improvements in muscular strength and short physical performance battery (SPPB) scores. A hybrid RET program with CrM was feasible, acceptable and well tolerated in individuals with colorectal cancer who were previously treated with chemotherapy. Hybrid supervised RET is safe, acceptable, and associated with modest improvements in strength and physical function among individuals treated for colorectal cancer. While creatine supplementation did not demonstrate clear additive effects in this pilot trial, further adequately powered studies are warranted. Trial Registration: NCT06420726.

Few investigations have evaluated the validity of current body composition technology among racially and ethnically diverse populations. This study assessed the validity of common body composition methods in a multi-ethnic sample stratified by race and ethnicity. One hundred and ten individuals (55 % female, age: 26·5 (sd 6·9) years) identifying as Asian, African American/Black, Caucasian/White, Hispanic, Multi-racial and Native American were enrolled. Seven body composition models (dual-energy X-ray absorptiometry (DXA), air displacement plethysmography (ADP), two bioelectrical impedance devices (BIS, IB) and three multi-compartment models) were evaluated against a four-compartment criterion model by assessing total error (TE) and standard error of the estimate. For the total sample, measures of % fat and fat-free mass (FFM) from multi-compartment models were all excellent to ideal (% fat: TE = 0·94–2·37 %; FFM: TE = 0·72–1·78 kg) compared with the criterion. % fat measures were very good to excellent for DXA, ADP and IB (TE = 2·52–2·89 %) and fairly good for BIS (TE = 4·12 %). For FFM, single device estimates were good (BIS; TE = 3·12 kg) to ideal (DXA, ADP, IB; TE = 1·21–2·15 kg). Results did not vary meaningfully between each race and ethnicity, except BIS was not valid for African American/Black, Caucasian/White and Multi-racial participants for % fat (TE = 4·3–4·9 %). The multi-compartment models evaluated can be utilised in a multi-ethnic sample and in each individual race and ethnicity to obtain highly valid results for % fat and FFM. Estimates from DXA, ADP and IB were also valid. The BIS may demonstrate greater TE for all racial and ethnic cohorts and results should be interpreted cautiously.