Sleep and stress hormone responses to training and competition in elite female athletes

Abstract

Stress hormone and sleep differences in a competition versus training setting are yet to be evaluated in elite female team-sport athletes. The aim of the current study was to evaluate salivary cortisol and perceptual stress markers during competition and training and to determine the subsequent effects on sleep indices in elite female athletes. Ten elite female netball athletes (mean ± SD; age: 23 ± 6 years) had their sleep monitored on three occasions; following one netball competition match (MATCH), one netball match simulation session (TRAIN), and one rest day (CONTROL). Perceived stress values and salivary cortisol were collected immediately pre- (17:15 pm) and post-session (19:30 pm), and at 22:00 pm. Sleep monitoring was performed using wrist actigraphy assessing total time in bed, total sleep time (TST), efficiency (SE%), latency, sleep onset time and wake time. Cortisol levels were significantly higher (p < .01) immediately post MATCH compared with TRAIN and CONTROL (mean ± SD; 0.700 ± 0.165, 0.178 ± 0.127 and 0.157 ± 0.178 μg/dL, respectively) and at 22:00 pm (0.155 ± 0.062, 0.077 ± 0.063, and 0.089 ± 0.083 μg/dL, respectively). There was a significant reduction in TST (-118 ± 112 min, p < .01) and SE (-7.7 ± 8.5%, p < .05) following MATCH vs. TRAIN. Salivary cortisol levels were significantly higher, and sleep quantity and quality were significantly reduced, following competition when compared to training and rest days.

Effects of training and competition on the sleep of elite athletes: a systematic review and meta-analysis

“…However, one of these found that TST was shorter the night of competition when ‘double-header’ fixtures (ie, two matches in 3 days) were played,67 and another found TST was shorter the night of competition compared with prior training 49. Similarly, the TST of netballers was shorter the night of a game compared with the night of a rest day41 74 and the night of a training day,74 while some evidence suggested TST was shorter the night of night-time compared with day competition,7 23 and the night of away compared with home competition 58…”

“…For example, increased circulating cortisol,74 sympathetic hyperactivity,83 elevated core body temperature84 and muscle pain85 may persist postcompetition and increase arousal 86 87. Cortisol levels following a race have been negatively (r=−0.90) correlated with SE in swimmers,32 while elevated cortisol postcompetition was associated with a reduction in TST the night of competition in netballers 74. Additionally, the ergogenic use of caffeine34 and exposure to bright light (eg, stadium lighting) may interfere with the neurological processes that promote sleep 88 89.…”

From pillow to podium: a review on understanding sleep for elite athletes

“…Although previous studies have assessed the effect of sporting competition on sleep, 41 – 44 few studies have examined the possible mechanisms contributing to poor sleep during competition. Research from our laboratory 45 examined the stress response and subsequent sleep response following an evening netball match and netball match simulated training session in 10 elite female netball athletes. Results showed significantly higher ( p <0.05) levels of cortisol immediately post and at 22:00 h on the match day compared to the match simulated training session (0.700 and 0.165 μg/dL, respectively).…”

Sleep Quality and Chronotype Differences between Elite Athletes and Non-Athlete Controls

“…Research in Australian Olympic swimmers found that during early morning training days, athletes obtained just 5.4 h of sleep on average, compared to 7.1 h of sleep on rest days [23]. Competing at night was associated with higher salivary cortisol and decreased quantity and quality of sleep [24]. An intervention study in collegiate basketball athletes documented that when sleep was extended from less than 7 h per night to more than 8 h per night, mood, sleepiness, reaction time, and shooting percentage were improved [10].…”