With the recent growth in female sport, practitioners need to be able to provide specific support to female athletes to ensure their sleep, health and athletic performance are optimised. Examine the patterns, duration and quality of sleep among elite female athletes, and consider the impact of situational challenges and their effects on the sleep of elite female athletes. Data was located through a search of SPORTDiscus, MEDLINE and Scopus from inception up to May 2021. Studies needed to be peer-reviewed research reporting quantitative sleep outcomes for female athletes ≥ 18 years of age and competing at a predefined elite level. A meta-analysis was performed on habitual sleep outcomes (e.g. total sleep time [TST] and sleep efficiency [SE]) measured with actigraphy. A total of 38 studies were included. Meta-analysis showed habitual TST (n = 14) was 7.8 h [7.4, 8.2] (mean [95% CI]), and SE was 86.7% [84.7, 88.6], with high variability among studies (I 2 = 97.8–98.2%). Subjective sleep complaints are common before a competition, as do post-training sleep disturbances (63% studies report TST decrease), and post-competition sleep disturbances (75% studies report TST decrease). Female athletes achieve satisfactory objective sleep quantity and quality during habitual periods, but experience sleep disturbances pre- and post-situational challenges. There is high variability of objective sleep outcomes, demonstrating the individual nature of habitual female athlete sleep. Overall, future research must focus on optimising the sleep appraisal methods and creating high-quality study designs in a broader number of sports.

PurposeThis study aimed to determine the effect of different air velocities on heat exchange and performance during prolonged self-paced exercise in the heat.MethodsTwelve male cyclists performed a 700-kJ time trial in four different air velocity conditions (still air, 16, 30, and 44 km·h−1) in 32°C and 40% relative humidity. Performance, thermal, cardiovascular, and perceptual responses were measured, and heat balance parameters were estimated using partitional calorimetry, including the maximum potential for sweat evaporation (Emax).ResultsMean power output was lower in still air (232 ± 42 W) than 16 (247 ± 30 W), 30 (250 ± 32 W), and 44 km·h−1 (248 ± 32 W; all P < 0.001), but similar between the 16-, 30-, and 44-km·h−1 air velocity conditions (P ≥ 0.275). Emax was lower in still air (160 ± 13 W·m−2) than 16 (298 ± 25 W·m−2), 30 (313 ± 23 W·m−2), and 44 km·h−1 (324 ± 31 W·m−2) and lower in 16 than 44 km·h−1 (all P < 0.001). Peak core temperature was higher in still air (39.4°C ± 0.7°C) than 16 (39.0°C ± 0.45°C), 30 (38.8°C ± 0.3°C), and 44 km·h−1 (38.8°C ± 0.5°C; all P ≤ 0.002). Mean skin temperature was lower with greater airflow (P < 0.001) but similar in 30 and 40 km·h−1 (P = 1.00). Mean heart rate was ~2 bpm higher in still air than 44 km·h−1 (P = 0.035). RPE was greater in still air than 44 km·h−1 (P = 0.017).ConclusionsSelf-paced cycling in still air was associated with a lower Emax and subsequently higher thermal strain, along with a similar or greater cardiovascular strain, despite work rate being lower than in conditions with airflow. The similarity in performance between the 16-, 30-, and 44-km·h−1 air velocity conditions suggests that airflow ≥16 km·h−1 does not further benefit self-paced exercise performance in the heat because of modest improvements in evaporative efficiency.

Both adult females and children have been reported to have a lower sweating capacity and thus reduced evaporative heat loss potential which may increase their susceptibility to exertional hyperthermia in the heat. Compared to males, females have a lower maximal sweat rate and thus a theoretically lower maximum skin wettedness, due to a lower sweat output per gland. Similarly, children have been suggested to be disadvantaged in high ambient temperatures due to a lower sweat production and therefore reduced evaporative capacity, despite modifications of heat transfer due to physical attributes and possible evaporative efficiency. The reported reductions in sudomotor activity of females and children suggests a lower sweating capacity in girls. However, due to the complexities of isolating sex and maturation from the confounding effects of morphological differences (e.g., body surface area-to-mass ratio) and metabolic heat production, limited evidence exists supporting whether children and, more specifically, girls are at a thermoregulatory disadvantage. Furthermore, a limited number of child-adult comparison studies involve females and very few studies have directly compared regional and whole-body sudomotor activity between boys and girls. This mini review highlights the exercise-induced sudomotor response of females and children, summarises previous research investigating the sudomotor response to exercise in girls and suggests important areas for further research.

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