Effects of a 20-Min Nap Post Normal and Jet Lag Conditions on P300 Components in Athletes

Abstract

Post-lunch sleepiness belongs to biological rhythms. Athletes take a nap to counteract afternoon circadian nadir, in prevision of disturbed sleep. This study examined the effects of brief post-lunch nap on vigilance in young and healthy athletes. The P300 components, physiological and cognitive performances were assessed either after nap or rest, following a night of normal sleep (NSC) or simulated jet lag condition (5-h advance-JLC). P300 wave is the positive deflection at about 300 ms in response to a rare stimulus, representing higher information processing. P300 amplitude reflects the amount of attention allocated whereas P300 latency reflects time spent on stimulus classification. P300 amplitude was significantly increased (Fz:11.14±3.0vs9.05±3.2 µV; p<0.05) and P300 latency was shorter (Pz:327.16±18.0vs344.90±17.0 ms; p<0.01) after nap in NSC. These changes were accompanied by lower subjective sleepiness (19.7±9.6vs27.5±16.5; p<0.05) and decrease in mean reaction times (MRT: divided attention, 645.1±74.2vs698±80.4 ms; p<0.05). In contrast, in JLC, only P300 amplitudes (Fz:10.30±3.1vs7.54±3.3 µV; p<0.01 and Cz: 11.48±3.1vs9.77±3.6 µV; p<0.05) increased but P300 latencies or MRT did not improve. These results indicated improvements in speed of stimulus evaluation time. Napping positively impacts on cognitive processing, especially when subjects are on normal sleep schedules. A nap should be planned for athletes whose performance requires speedy and accurate decisions.

To Nap or Not to Nap? A Systematic Review Evaluating Napping Behavior in Athletes and the Impact on Various Measures of Athletic Performance

“… 5 , 6 , 8 , 24–57 Both males and females were included in 35.1% (n = 13) of studies, 5 , 6 , 8 , 29 , 30 , 32 , 34–36 , 41 , 48 , 50 , 51 8.1% (n = 3) of studies included females exclusively, 37 , 38 , 57 and 48.6% (n = 18) studies included males only. 24–26 , 31 , 33 , 37 , 40 , 42 , 43 , 45–47 , 49 , 52–56 Three studies (8.1%) did not report sex. 27 , 28 , 44 The mean age of athletes was 23±4 years.…”

“… 27 , 28 , 44 The mean age of athletes was 23±4 years. Study designs were as follows: cross-sectional (n = 6), 25–30 longitudinal/cohort (n = 14), 5 , 6 , 31–39 , 41 , 57 , 58 randomized experimental (n = 14), 24 , 42–49 , 52–56 and non-randomized experimental (n = 3). 8 , 48 , 50 Athletes participated in 11 different sports (ie, karate, judo, netball, rowing, rugby, running, soccer, swimming, shooting marksmanship, track and field, and ultramarathon).…”

Nap Opportunity During the Daytime Affects Performance and Perceived Exertion in 5-m Shuttle Run Test

“…Additionally, several studies suggest that a nap could reduce fatigue and improve vigor, subjective alertness, objective vigilance, and cognitive performance (Brooks and Lack, 2006;Verweij et al, 2016). Recently, Petit et al (2018) showed that a 20 min nap has a beneficial effect on information processing (using the P300 test which measures the positive deflection at about 300 ms in response to a rare stimulus), alertness, and cognitive processing in athletes. O’Donnell et al (2018) showed that a short nap (i.e., <20 min) opportunity enhanced the subjective estimation of performance in elite netball players (i.e., by coaches) and the jump velocity during the day of the competition.…”

How to manage travel fatigue and jet lag in athletes? A systematic review of interventions

“…No relevant travel fatigue papers were found. For jet lag, three interventions (exercise: 4, [29][30][31][32] sleep: 3, [33][34][35] light: 2 30 36 ) yielded athlete-specific studies. There were no athlete-specific studies for the category on nutrition (mealtime/composition) and we subsequently inferred from two healthy population studies.…”

“…Literature supports sleep preservation as an important strategy of jet lag management. 8 In an athlete specific study, Petit et al 34 showed that a strategic 20 min nap between 08:00 and 09:00 following a simulated 5-hour phase-shift, may alleviate jet lag and result in increased cognitive performance. Petit et al 33 further conducted a randomised crossover counterbalanced design investigating a simulated 5-hour phase-advance, and found no changes in physical performance or facilitation of resynchronisation after a 20 min post-lunch nap.…”