International society of sports nutrition position stand: ketogenic diets.

Position Statement: The International Society of Sports Nutrition (ISSN) provides an objective and critical review of the use of a ketogenic diet in healthy exercising adults, with a focus on exercise performance and body composition. However, this review does not address the use of exogenous ketone supplements. The following points summarize the position of the ISSN.

Differences in Injury Profiles Between Female and Male Athletes Across the Participant Classification Framework: A Systematic Review and Meta-Analysis.

Background: Female sex is a significant determinant of anterior cruciate ligament (ACL) injury. It is not understood if sex is a key determinant of other sports-related injuries.

Objective: The aim of this systematic review was to identify where differences in injury profiles are most apparent between the sexes in all sports across the six-tiered participant classification framework.

Pre-sleep feeding, sleep quality, and markers of recovery in division I NCAA female soccer players.

Pre-sleep nutrition habits in elite female athletes have yet to be evaluated. A retrospective analysis was performed with 14 NCAA Division I female soccer players who wore a WHOOP, Inc. band - a wearable device that quantifies recovery by measuring sleep, activity, and heart rate metrics through actigraphy and photoplethysmography, respectively - 24 h a day for an entire competitive season to measure sleep and recovery.

International society of sports nutrition position stand: nutritional concerns of the female athlete.

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.

Heating Up to Keep Cool: Benefits and Persistence of a Practical Heat Acclimation Protocol in Elite Female Olympic Team-Sport Athletes.

Purpose: Although recommendations for effective heat acclimation (HA) strategies for many circumstances exist, best-practice HA protocols specific to elite female team-sport athletes are yet to be established. Therefore, the authors aimed to investigate the effectiveness and retention of a passive HA protocol integrated in a female Olympic rugby sevens team training program.

Methods: Twelve elite female rugby sevens athletes undertook 10 days of passive HA across 2 training weeks.

Advancing feminist innovation in sport studies: A transdisciplinary dialogue on gender, health and wellbeing.

Athlete health and wellbeing requires a holistic, multidimensional approach to understanding, supporting, and treating individual athletes. Building more supportive, inclusive, and equitable environments for the health and wellbeing of women and gender expansive people further requires gender-responsive approaches that promote broader cultural change. Feminist sport and exercise medicine practitioners, sports scientists, and social science researchers are increasingly coming together in their efforts to do this work.

The Influence of Full-Time Holistic Support Delivered by a Sports Nutritionist on Within-Day Macronutrient Distribution in New Zealand Provincial Academy Rugby Union Players.

Dietary intake is an important consideration for rugby union ('rugby') players to ensure substrate provision for optimal performance and facilitate recovery. Within-day meal distribution is especially important for athletes, particularly those with congested schedules and multiple daily training sessions. In the present study, 10 provincial academy rugby players engaged in a holistic support protocol informed by behaviour-change techniques led by a full-time sports nutritionist.

High Prevalence of Iron Deficiency Exhibited in Internationally Competitive, Non-Professional Female Endurance Athletes-A Case Study.

Background: While iron deficiency is commonly discussed in populations of professional female athletes, less is known about highly trained, sub-elite female athletes (e.g., those winning international age-group competitions) who generally have less access to medical and allied health support.

Case Study: Energy Availability and Endocrine Markers in Elite Male Track Cyclists.

Aim: To highlight energy availability status, resting metabolic rate measures, dietary protein intake, and testosterone concentration in 4 elite male track cycling athletes (mean [SD]: age: 20.8 [1.5] y, body mass: 76.

Patterns of endogenous and exogenous ovarian hormone modulation on recovery metrics across the menstrual cycle.

Introduction: As the number of female athletes competing rises globally, training methodologies should reflect sex differences across critical metrics of adaptation to training. Surrogate markers of the autonomic nervous system (ANS) used for monitoring training load are heart rate variability (HRV) and resting heart rate (RHR). The aim was to investigate ovarian hormone effects on standard recovery metrics (HRV, RHR, respiratory rate (RR) and sleep duration) across a large population of female athletes.

Biological and Socio-Cultural Factors Have the Potential to Influence the Health and Performance of Elite Female Athletes: A Cross Sectional Survey of 219 Elite Female Athletes in Aotearoa New Zealand.

Health is a pre-requisite for optimal performance yet the parameters which govern health and performance of elite female athletes are little understood. The aim of this study was to quantify the health status of elite female athletes, and understand sociocultural factors influencing that status. The survey addressed demographic, health and athletic performance history, training load, contraceptive use, sport-specific appearance and performance pressures, and communication barriers.

Where are all the men? Low energy availability in male cyclists: A review.

Most of the low energy availability (LEA) research has been conducted in female populations. The occurrence of LEA in male athletes is not well known, even with an understanding of the components involved in and contributing to LEA. Cycling is a major risk factor for LEA due to inherent sports characteristics: low impact, high energy demands, and a common perception that leanness is a performance advantage.

Menstrual cycle and thermoregulation during exercise in the heat: A systematic review and meta-analysis.

Unlabelled: Research conducted on exercise in the heat has been largely conducted in males, leaving women understudied. Of research including women, results are inconsistent on the impact of menstrual cycle phase on thermoregulation.

Objectives: The purpose of this systematic review is to quantify published investigations in thermal physiology that include menstrual cycle comparisons and assess aggregate data of investigations that include menstrual cycle variation and aerobic exercise in the heat.

Hepcidin and iron: novel findings for elite female rugby Sevens players.

Background: Iron deficiency is a common deficiency disease worldwide with athletes at increased risk.

Methods: A proposed new mechanism of exercise-induced iron deficiency in athletes involves the iron-regulatory hormone hepcidin, however, there is limited information on this amongst elite athletes. This study describes iron status in elite female rugby Sevens players.

The Validity of Resting Metabolic Rate-Prediction Equations and Reliability of Measured RMR in Female Athletes.

The aim of the current study was to; 1) assess the test-retest reliability of an indirect calorimetry analyzer (Parvo Medics TrueOne), and 2) compare measured RMR with three RMR-predictive (pRMR) equations in female athletes. In part one, 12 recreationally-exercising women (mean ± SD; age 27.5 ± 12.

Myths and Methodologies: Reducing scientific design ambiguity in studies comparing sexes and/or menstrual cycle phases.

New Findings: What is the topic of this review? We review methodological considerations for the inclusion of women in sex and menstrual cycle phase comparison studies. What advances does it highlight? Improving the methodological design for studies exploring sex differences, menstrual cycle phase differences and/or endogenous versus exogenous female sex hormones will help to close the gap in our understanding of the effects of endogenous and exogenous hormones on exercise science and sports medicine outcomes.

Abstract: In recent years, the increase in scientific literature exploring sex differences has been beneficial to both clinicians and allied health science professionals, although female athletes are still significantly under-represented in sport and exercise science research.

Fluid intake behavior in athletes during typical training bouts.

Background: Hydration habits during training may differ depending on sports mode and individual characteristics. The aim of this study was to assess fluid intake behavior in a wide sample of Italian athletes during their regular training.

Methods: Data on hydration habits during training were collected from a random sample of competitive athletes.

Lower skin cancer risk in women with higher body mass index: the women's health initiative observational study.

The unclear relationship of obesity to incident melanoma and nonmelanoma skin cancer (NMSC) risks was evaluated in the large, geographically diverse longitudinal, prospective Women's Health Initiative (WHI) observational study. Risks of melanoma and NMSC in normal weight women were compared with risks in overweight [body mass index (BMI) = 25-29.0 kg/m(2)] and obese (BMI ≥ 30 kg/m(2)) women, using Cox proportional hazards models for melanoma and logistic regression for NMSC.

Low-fat diet and skin cancer risk: the women's health initiative randomized controlled dietary modification trial.

Background: Large cohort studies have reported no relationship between dietary fat and nonmelanoma skin cancer (NMSC), although a low-fat diet intervention reduced NMSC risk in a small clinical trial. In animal studies, skin tumor development has been reduced by low-fat diet. We evaluated the effect of a low-fat dietary pattern on NMSC and melanoma in the Women's Health Initiative Dietary Modification trial.

Relationship of sedentary behavior and physical activity to incident cardiovascular disease: results from the Women's Health Initiative.

Objectives: The aim of this study was to examine the independent and joint associations of sitting time and physical activity with risk of incident cardiovascular disease (CVD).

Background: Sedentary behavior is recognized as a distinct construct beyond lack of leisure-time physical activity, but limited data exist on the interrelationship between these 2 components of energy balance.

Methods: Participants in the prospective Women's Health Initiative Observational Study (n = 71,018), 50 to 79 years of age and free of CVD at baseline (1993 to 1998), provided information on sedentary behavior, defined as hours of sitting/day, and usual physical activity at baseline and during follow-up through September 2010.

Changes in physical activity and body composition in postmenopausal women over time.

Purpose: Higher physical activity (PA) has been associated with greater attenuation of body fat gain and preservation of lean mass across the lifespan. These analyses aimed to determine relationships of change in PA to changes in fat and lean body mass in a longitudinal prospective study of postmenopausal women.

Methods: Among 11,491 women enrolled at three Women's Health Initiative clinical centers who were selected to undergo dual-energy x-ray absorptiometry, 8352 had baseline body composition measurements, with at least one repeated measure at years 1, 3, and 6.

The effect of a cold beverage during an exercise session combining both strength and energy systems development training on core temperature and markers of performance.

Background: Although studies have investigated the effects of hydration on performance measures, few studies have investigated how the temperature of the ingested liquid affects performance and core temperature during an exercise session. The hypothesis of the present study was that cold water would improve thermoregulation and performance as measured by bench repetitions to fatigue, broad jump for force and power and total time to exhaustion for cardiovascular fitness

Methods: Forty-five, physically fit, adult males (30.28 ± 5.

Effects of a dietary intervention and weight change on vasomotor symptoms in the Women's Health Initiative.

Objective: The aim of this study was to determine whether a dietary intervention designed to reduce fat intake and increase intake of fruit, vegetables, and whole grains, and weight loss, reduces vasomotor symptoms (VMS; ie, hot flashes or night sweats) in postmenopausal women.

Methods: We included 17,473 postmenopausal US women, ages 50 to 79 years, at baseline who participated in the Women's Health Initiative Dietary Modification trial and were not taking menopausal hormone therapy. Logistic regression was used to evaluate associations.

Physical activity and body mass: changes in younger versus older postmenopausal women.

Purpose: The study's purpose was to investigate the relationship of sedentary (≤ 100 MET · min · wk(-1)), low (>100-500 MET · min · wk(-1)), moderate (>500-1200 MET · min · wk(-1)), and high (>1200 MET · min · wk(-1)) habitual physical activity with body weight, body mass index, and measures of fat distribution (waist-to-hip ratio) in postmenopausal women by age decades.

Methods: A prospective cohort study of 58,610 postmenopausal women age 50-79 yr weighed annually during 8 yr at one of 40 US clinical centers was analyzed to determine the relationship of high versus low habitual physical activity with changes in body weight and fat distribution by age group.

Results: Among women age 50-59 yr, there was significant weight loss in those expending >500-1200 MET · min · wk(-1) (coefficient = -0.