A good diet is necessary for athletes to meet their energy needs and attain their peak level of health and performance. Energy availability (EA) is the amount of energy available for normal metabolic function following exercise energy expenditure . Low energy availability (LEA) develops when an individual or athlete consumes a low energy intake that is relative to expending a high exercise energy expenditure (EEE), which can occur intentionally in athletes who wish to lose weight or maintain a lower body weight through dietary restriction.
The current obesity epidemic is a global health issue evidencedthrough a tripling of obesity incidence since 1975 and has emergedas the leading cause of non-communicable diseases (WHO, 2021).Individuals with overweight or obesity, defined as body mass index(BMI) ≥25 and ≥30 kg·m2, respectively, are at higher risk ofimpaired metabolic homeostasis, reduced insulin sensitivity(Krogh-Madsen et al., 2010) and postprandial lipid metabolism(Booth et al., 2012), which can be contributed by physicalinactivity (WHO, 2021).
To improve sports performance, overall health and well-being, as well as to reduce the risk of injury, it is essential for athletes to consume optimal nutrients (Kerksick et al., 2018; Thomas et al., 2016). In general, athletes should get sufficient energyfrom natural sources to provide them with adequate amounts of carbohydrate, protein and fat. Besides that, an athlete’s training plan, competition target and food preferences should also be considered (Thomas et al., 2016). When athletes do not follow these recommendations, their performance may be affected.
The severe acute respiratory syndrome coronavirus 2-mediated coronavirus disease 2019 (COVID-19) pandemic enforced global change upon day-to-day life. Most nations responded with one or more periods of localised or country-wide lockdowns, resulting in increased anxiety and depression, sedentary lifestyle, and ‘screen time’. Holistically, lockdown-mediated home confnement resulted in lower social participation and life satisfaction, increased psychological strain, social and physical inactivity, an unhealthy diet, and poor sleep hygiene, particularly among female and younger individuals.
Healthy adult Muslims fast for 29–30 days each year during Ramadan. Eating and drinking are not permitted between dawn (imsak) and sunset (iftar), a duration generally ~10–22 hours, dependent on geographical location. At extreme latitudes where an absence of sunrise/sunset occurs, clerical decree’s set fasting hours. Ramadan intermittent fasting (RIF) through various religious and nonreligious forms, particularly the former, modifies sleep-wake cycles and eating patterns, generally disrupting ‘normal’ lifestyle whilst compromising physical and cognitive performance. Blood glucose levels, hydration status and availability of metabolites for short explosive and endurance physical efforts are likely sub-optimal during this fasting period. These challenges are evidently more pronounced in athletic compared to sedentary populations undertaking RIF.
Research has found that reducing training intensity during the COVID-19-induced lockdown. And it was associated with lower sleep quality and higher insomnia severity in elite athletes. Lockdown duration had further disrupting effects on elite athletes’ sleep behavior.
Obesity is a major global health issue and a primary risk factor for metabolic-related disorders. While physical inactivity is one of the main contributors to obesity, it is a modifiable risk factor with exercise training as an established non-pharmacological treatment to prevent the onset of metabolic-related disorders, including obesity. Exposure to hypoxia via normobaric hypoxia (simulated altitude via reduced inspired oxygen fraction), termed hypoxic conditioning, in combination with exercise has been increasingly shown in the last decade to enhance blood glucose regulation and decrease the body mass index, providing a feasible strategy to treat obesity. However, there is no current consensus in the literature regarding the optimal combination of exercise variables such as the mode, duration, and intensity of exercise, as well as the level of hypoxia to maximize fat loss and overall body compositional changes with hypoxic conditioning.