The Afternoon Slump
We have all been there: it is late afternoon, you have a training session or a game ahead, but your energy levels are bottoming out. For athletes, the question often arises: should I nap, should I reach for a pre-workout, or should I do both? A recent study published in the International Journal of Sport Nutrition and Exercise Metabolism (PMID: 42086212) provides some evidence-based clarity.
The Study Design
Researchers investigated the effects of a 90-minute early afternoon nap (12:30 p.m.) and a moderate dose of caffeine (5 mg/kg) taken in the early evening (6:00 p.m.) on physical performance at 7:00 p.m. Using a randomized, double-blind, placebo-controlled design, 13 physical education students were tested across four conditions: placebo, nap only, caffeine only, and a combination of both.
Key Findings
Interestingly, the study found no significant differences between the interventions regarding subjective sleepiness or reaction times. However, the physical performance results tell a different story:
- Repeated Agility: All interventions (nap, caffeine, and the combination) improved performance in the repeated modified agility test compared to the placebo, though there was no significant difference between the interventions themselves.
- Explosivity: When it came to squat jump performance, all interventions outperformed the placebo. Crucially, the combination of a nap and caffeine yielded the greatest improvements in squat jump height, take-off velocity, and relative power compared to using either strategy alone.
Practical Application
If you are an athlete competing in team or racket sports during the evening, this data suggests that combining a 90-minute nap with a moderate dose of caffeine might provide a distinct edge in explosive movements.
However, a word of caution: the researchers noted that the limited effects on non-explosive tasks and the potential for sleep disruption mean this strategy should be used strategically. If you struggle with sleep hygiene, a 90-minute nap and late-afternoon caffeine might do more harm than good for your long-term recovery. Always test these protocols in training before applying them to competition.
Note: This article is based on an abstract-only review of the study.