Impact of acute dietary and exercise manipulation on next day RMR measurements and DXA body composition estimates.

Purpose: To investigate the effects of acute diet and exercise manipulation on resting metabolic rate (RMR) measurement variability and dual energy x-ray absorptiometry (DXA) body composition estimates.

Methods: 10 male and 10 female endurance athletes (12 cyclists, 5 triathletes, 4 runners) of Tier 2 (n = 18) to Tier 3 (n = 2) calibre underwent five conditions using a Latin square counterbalance design. For 24 hours, athletes consumed a diet providing excessive energy availability (75 kcal‧kg fat free mass (FFM) -1 ) without exercise (GEA rest ), high energy availability (45 kcal‧kg FFM -1 ) without (HEA rest ) or with exercise (HEA ex ), or low-energy availability (15 kcal‧kg FFM -1 ) without (LEA rest ) or with exercise (LEA ex ).

The Temporal Effects of Altitude and Low Energy Availability Manipulation on Resting Metabolic Rate in Female Race Walkers.

Purpose: This study aimed to investigate the temporal effects of ~1800 m altitude exposure and energy availability (EA) manipulation on resting metabolic rate (RMR).

Methods: Twenty elite female race walkers underwent a 3-wk training camp at an altitude of ~1800 m. During the first 2 wk, athletes consumed a high EA (HEA) diet of 45 kcal·kg fat-free mass (FFM) -1 ·d -1 .

Auditing the representation of hormonal contraceptives in studies assessing exercise performance in women.

Hormonal contraceptive (HC) users have a different ovarian hormonal profile compared to eumenorrheic women. Due to the prevalence of HC use amongst sportswomen, there has been increased research efforts to understand their impact on exercise performance. The aim was to audit this research.

Minimal influence of the menstrual cycle or hormonal contraceptives on performance in female rugby league athletes.

We examined performance across one menstrual cycle (MC) and 3 weeks of hormonal contraceptives (HC) use to identify whether known fluctuations in estrogen and progesterone/progestin are associated with functional performance changes. National Rugby League Indigenous Women's Academy athletes [n = 11 naturally menstruating (NM), n = 13 using HC] completed performance tests [countermovement jump (CMJ), squat jump (SJ), isometric mid-thigh pull, 20 m sprint, power pass and Stroop test] during three phases of a MC or three weeks of HC usage, confirmed through ovulation tests alongside serum estrogen and progesterone concentrations. MC phase or HC use did not influence jump height, peak force, sprint time, distance thrown or Stroop effect.

Effect of Menstrual Cycle Phase and Hormonal Contraceptives on Resting Metabolic Rate and Body Composition.

The cyclical changes in sex hormones across the menstrual cycle (MC) are associated with various biological changes that may alter resting metabolic rate (RMR) and body composition estimates. Hormonal contraceptive (HC) use must also be considered given their impact on endogenous sex hormone concentrations and synchronous exogenous profiles. The purpose of this study was to determine if RMR and dual-energy X-ray absorptiometry body composition estimates change across the MC and differ compared with HC users.

Female Athlete Representation and Dietary Control Methods Among Studies Assessing Chronic Carbohydrate Approaches to Support Training.

The aim of this audit was to assess the representation of female athletes, dietary control methods, and gold standard female methodology that underpins the current guidelines for chronic carbohydrate (CHO) intake strategies for athlete daily training diets. Using a standardized audit, 281 studies were identified that examined high versus moderate CHO, periodized CHO availability, and/or low CHO, high fat diets. There were 3,735 total participants across these studies with only ∼16% of participants being women.

Fueling the Female Athlete: Auditing Her Representation in Studies of Acute Carbohydrate Intake for Exercise.

Purpose: The aim of this audit was to assess the representation of female athletes within the literature that has led to current guidelines for carbohydrate (CHO) intake in the acute periods surrounding exercise and the quality of this research.

Methods: We conducted a standardized audit of research assessing CHO loading protocols, CHO mouth rinse, and CHO intake before, during, and after exercise.

Results: A total of 937 studies were identified in this audit.

Markers of Low Energy Availability in Overreached Athletes: A Systematic Review and Meta-analysis.

Background: Overreaching is the transient reduction in performance that occurs following training overload and is driven by an imbalance between stress and recovery. Low energy availability (LEA) may drive underperformance by compounding training stress; however, this has yet to be investigated systematically.

Objective: The aim of this study was to quantify changes in markers of LEA in athletes who demonstrated underperformance, and exercise performance in athletes with markers of LEA.

Blood flow restriction and stimulated muscle contractions do not improve metabolic or vascular outcomes following glucose ingestion in young, active individuals.

Glucose ingestion and absorption into the bloodstream can challenge glycemic regulation and vascular endothelial function. Muscular contractions in exercise promote a return to homeostasis by increasing glucose uptake and blood flow. Similarly, muscle hypoxia supports glycemic regulation by increasing glucose oxidation.

Examining the Relationship between Exercise Dependence, Disordered Eating, and Low Energy Availability.

Both dietary and exercise behaviors need to be considered when examining underlying causes of low energy availability (LEA). The study assessed if exercise dependence is independently related to the risk of LEA with consideration of disordered eating and athlete calibre. Via survey response, female ( = 642) and male ( = 257) athletes were categorized by risk of: disordered eating, exercise dependence, disordered eating and exercise dependence, or if not presenting with disordered eating or exercise dependence as controls.

A Review of Nonpharmacological Strategies in the Treatment of Relative Energy Deficiency in Sport.

Relative energy deficiency in sport (RED-S) can result in negative health and performance outcomes in both male and female athletes. The underlying etiology of RED-S is low energy availability (LEA), which occurs when there is insufficient dietary energy intake to meet exercise energy expenditure, corrected for fat-free mass, leaving inadequate energy available to ensure homeostasis and adequate energy turnover (optimize normal bodily functions to positively impact health), but also optimizing recovery, training adaptations, and performance. As such, treatment of RED-S involves increasing energy intake and/or decreasing exercise energy expenditure to address the underlying LEA.