The longer the better: Sleep–wake patterns during preparation of the World Rowing Junior Championships

Abstract

Recovery is essential for high athletic performance, and therefore especially sleep has been identified as a crucial source for physical and psychological well-being. However, due to early-morning trainings, which are general practice in many sports, athletes are likely to experience sleep restrictions. Therefore, this study investigated the sleep-wake patterns of 55 junior national rowers (17.7 ± 0.6 years) via sleep logs and actigraphy during a four-week training camp. Recovery and stress ratings were obtained every morning with the Short Recovery and Stress Scale on a 7-point Likert-type scale ranging from 0 (does not apply at all) to 6 (fully applies). The first training session was scheduled for 6:30 h every day. With two to four training sessions per day, the training load was considerably increased from athletes' home training. Objective sleep measures (n = 14) revealed less total sleep time (TST) in the first two weeks (409.6 ± 19.1 and 416.0 ± 16.3 min), while training volume and intensity were higher. In the second half of the camp, less training sessions were implemented, more afternoons were training free and TSTs were longer (436.3 ± 15.8 and 456.9 ± 25.7 min). A single occasion of 1.5-h delayed bedtime and usual early morning training (6:30 h) resulted in reduced ratings of Overall Recovery (OR) (M = 3.3 ± 1.3) and greater Negative Emotional State (NES) (M = 1.3 ± 1.2, p < .05), which returned to baseline on the next day. Following an extended night due to the only training-free day, sleep-offset times were shifted from ~5:30 to ~8:00 h, and each recovery and stress score improved (p < .01). Moreover, subjective ratings of the first six days were summarised as a baseline score to generate reference data as well as to explore the association between sleep and recovery. Intercorrelations of these sleep parameters emphasised the relationship between restful sleep and falling asleep quickly (r = .34, p < .05) as well as few awakenings (r = .35, p < .05). Overall, the findings highlight the impact of sleep on subjective recovery measures in the setting of a training camp. Providing the opportunity of extended sleep (and a day off) seems the most simple and effective strategy to enhance recovery and stress-related ratings.

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

“…Rugby league players, synchronised swimmers and cyclists had reduced TST and SE following large increases (>25%) in training load 48 65 69. Rowers also had shorter TST, but no change in SE, during periods of higher training load,43 while distance covered during training negatively correlated with subsequent TST (r=−0.31) among rugby league players 69. Shorter TST was also observed among rowers in the final days of a training camp compared with subsequent nights at a competition when sleep opportunities increased 44.…”

“…While athletes try to offset the effects of early training by going to bed earlier, it is often difficult to prevent reductions in TST 63. For example, on a training camp, rowers woke approximately 2.5 hours earlier on training days compared with rest days, but went to bed just 25 min earlier the night before 43. The inability to go to bed early has been attributed to the fact that most social engagements are scheduled in the evening, and the so-called ‘forbidden zone’—a period of heightened arousal mediated by the body’s circadian rhythms—typically reduces sleep propensity between 20:00 and 22:00 63…”

Does Elite Sport Degrade Sleep Quality? A Systematic Review

“…Only two studies assessed sleep quality, with one of these reporting a reduction in ‘sleep restfulness’ on a training day compared with a rest day. Three studies quantified levels of daytime sleep [32, 33, 60]. Sargent et al [32] found elite athletes to nap at similar frequencies on training (15% of 14 days) and rest days (16% of 14 days).…”

“…Sargent et al [32] found elite athletes to nap at similar frequencies on training (15% of 14 days) and rest days (16% of 14 days). However, Kölling et al [60] reported that the proportion of elite rowers who napped on training days (43%, n  = 24) was greater than that for rest days (16%, n  = 9).…”

“…In the studies reporting comparisons between intensified and normal training, significant decreases in total sleep time were observed in all actigraphy studies [53, 60]. However, changes in rise time, sleep onset latency, sleep efficiency and sleep quality were equivocal.…”