Skeletal muscle is a direct target for vitamin D. Observational studies suggest that low 25[OH]D correlates with functional recovery of skeletal muscle following eccentric contractions in humans and crush injury in rats. However, a definitive association is yet to be established. To address this gap in knowledge in relation to damage repair, a randomised, placebo-controlled trial was performed in 20 males with insufficient concentrations of serum 25(OH)D (45 ± 25 nmol/l). Prior to and following 6 wk of supplemental vitamin D3 (4,000 IU/day) or placebo (50 mg of cellulose), participants performed 20 × 10 damaging eccentric contractions of the knee extensors, with peak torque measured over the following 7 days of recovery. Parallel experimentation using isolated human skeletal muscle-derived myoblast cells from biopsies of 14 males with low serum 25(OH)D (37 ± 11 nmol/l) were subjected to mechanical wound injury, which enabled corresponding in vitro studies of muscle repair, regeneration, and hypertrophy in the presence and absence of 10 or 100 nmol 1α,25(OH)2D3. Supplemental vitamin D3 increased serum 25(OH)D and improved recovery of peak torque at 48 h and 7 days postexercise. In vitro, 10 nmol 1α,25(OH)2D3 improved muscle cell migration dynamics and resulted in improved myotube fusion/differentiation at the biochemical, morphological, and molecular level together with increased myotube hypertrophy at 7 and 10 days postdamage. Together, these preliminary data are the first to characterize a role for vitamin D in human skeletal muscle regeneration and suggest that maintaining serum 25(OH)D may be beneficial for enhancing reparative processes and potentially for facilitating subsequent hypertrophy.

Physique competitions are events in which aesthetic appearance and posing ability are valued above physical performance. Female physique athletes are required to possess high lean body mass and extremely low fat mass in competition. As such, extended periods of reduced energy intake and intensive training regimens are used with acute weight loss practices at the end of the precompetition phase. This represents an increased risk for chronic low energy availability and associated symptoms of relative energy deficiency in sport, compromising both psychological and physiological health. Available literature suggests that a large proportion of female physique athletes report menstrual irregularities (e.g., amenorrhea and oligomenorrhea), which are unlikely to normalize immediately postcompetition. Furthermore, the tendency to reduce intakes of numerous essential micronutrients is prominent among those using restrictive eating patterns. Following competition, reduced resting metabolic rate, and hyperphagia, is also a concern for these female athletes, which can result in frequent weight cycling, distorted body image, and disordered eating/eating disorders. Overall, female physique athletes are an understudied population, and the need for more robust studies to detect low energy availability and associated health effects is warranted. This narrative review aims to define the natural female physique athlete, explore some of the physiological and psychological implications of weight management practices experienced by female physique athletes, and propose future research directions.

Little is known about weight loss practices and eating behaviours in female physique athletes. This study investigated the weight loss history, practices, and key influences during the pre-competition period in a large cohort of female physique athletes stratified by division and experience level. Eating attitudes and behaviours were assessed to identify whether athletes were at risk of developing an eating disorder. Using a cross-sectional research design, female physique athletes (n = 158) were recruited and completed an anonymous online self-reported survey consisting of two validated questionnaires: Rapid Weight Loss Questionnaire and Eating Attitudes Test-26. Irrespective of division or experience, female physique athletes used a combination of weight loss practices during the pre-competition phase. Gradual dieting (94%), food restriction (64%) and excessive exercise (84%), followed by body water manipulation via water loading (73%) were the most commonly used methods. Overall, 37% of female physique athletes were considered at risk of developing an eating disorder. Additionally, 42% of female physique athletes used two pathogenic weight control methods with 34% of Figure novice athletes indicating binge eating once a week or more. The coach (89%) and another athlete (73%) were identified as key influences on athletes’ dieting practices and weight loss. The prevalence of athletes identified with disordered eating symptoms and engaging in pathogenic weight control methods is concerning. In future, female physique athletes should seek advice from registered nutritionists to optimise weight management practices and minimise the risk of developing an eating disorder.