Sleep and Performance: A Load of Old Bollocks?
When it comes to achieving peak physical performance we hear plenty about new training regimes, nutrition plans, and electrolyte doohickies. But there’s one performance booster you’re probably missing: sleep.
It’s the unsung hero of performance, and it’s not just for elite athletes. Whether you’re training for a marathon, or hitting the gym to build a better you, sleep plays a critical role in ensuring you perform at your peak. In fact, as sleep science advances, the message is clear: sleep may well be the greatest legal performance-enhancing drug available to us. Let’s explore why.
The Impact of Sleep on Physical Performance
When we skimp on sleep, our bodies and brains pay the price in multiple ways, all of which erode our athletic ability. Here’s how a lack of sleep undermines your performance:
1. Reduced Strength and Power
If you’ve been training hard, poor sleep can undo much of that effort. Studies show that a lack of sleep directly reduces your peak performance strength. Whether it’s your vertical jump height, bench press maximum, or squat ability, insufficient sleep means you’re not performing at your true capacity.
2. Impaired Oxygen and Endurance
Your lungs are vital in expelling carbon dioxide and bringing in oxygen—the fuel for your muscles. A lack of sleep reduces this ability, making physical activities more exhausting, faster. For endurance athletes, this can be devastating. Imagine training diligently for a 10K race, only to find yourself running out of steam by kilometre 7 simply because you didn’t get enough sleep in the lead up to the race.
Research suggests that sleep deprivation can decrease your time to physical exhaustion by anywhere from 15 to 30%.
3. Disrupted Cooling Systems
Sweating is your body’s natural cooling mechanism. If you can’t cool down properly, your performance drops—it’s that simple. Lack of sleep disrupts this process, preventing you from efficiently perspiring, which means your body temperature rises, and key functions begin to degrade.
4. Faster Lactic Acid Buildup
We all know the burn that comes with intense exercise—that’s lactic acid buildup. Sleep deprivation accelerates this build up of lactic acid in your muscles, increasing the risk of painful cramps and spasms that can take you out of the game entirely. Ain’t nobody got that time for that.
5. Increased Risk of Injury
If there’s one point to hammer home, it’s this: poor sleep significantly increases your risk of injury. Meta-analyses of multiple studies show that both the quantity and quality of your sleep directly correlate to your injury risk. Athletes who sleep less are far more likely to sustain injuries over a season. For professional athletes, this is costly. For the rest of us, it’s equally frustrating and demotivating. In the longer-term, sleep also appears to play an important role in preventing the occurrence of overreaching or even overtraining syndrome.
Why Sleep is the Best Recovery Tool
Sleep doesn’t just prepare you for peak performance—it also helps your body recover and rebuild. During deep sleep, your body:
Reduces inflammation in joints and tissues.
Replenishes critical energy stores, such as glucose and glycogen, within your muscles.
Repairs damaged muscle fibres, making you stronger and more resilient.
In other words, sleep is essential both before and after physical activity.
Exercise Improves Your Sleep—A Beautiful Feedback Loop
The relationship between sleep and exercise isn’t a one-way street. While sleep boosts your physical performance, physical activity also improves your sleep.
Here’s what the science says about regular exercise and its impact on sleep quality:
Longer Sleep Duration: People who exercise regularly sleep longer, on average, than those who are sedentary.
Better Sleep Quality: Regular exercisers report fewer awakenings during the night, leading to more continuous, uninterrupted sleep.
Deeper Sleep: Particularly in midlife and later years, exercise promotes more deep non-REM sleep (stages 3 and 4), which is critical for recovery.
The takeaway? If you want to sleep better, move more.
Timing Your Exercise for Better Sleep
Exercise helps improve sleep, but timing is crucial. Intense workouts in the last two hours before bedtime can make it harder to fall asleep, since they raise your heart rate, release stimulating chemicals like endorphins, and increase your body temperature—an effect that can be further amplified by a post-workout shower. If you’re a fan of evening workouts, try to finish a few hours before bedtime to allow your body to cool down and wind down naturally.
Sleep and Skill Development: It’s Not Just Physical
Beyond the physical, sleep also enhances your motor skills and muscle memory—the essential elements for mastering technique and precision in sports.
Think of it this way: practice doesn’t make perfect—practice followed by sleep does. Whether you’re perfecting your golf swing, free kicks, or even learning a new skill like latte art, your brain consolidates and strengthens those skills during sleep. Studies show that motor performance improves by up to 30% overnight with sufficient sleep—even without additional practice.
So, the next time you’re tempted to stay up late or skip a few extra hours of sleep, remember that a good night’s sleep might be the secret ingredient that takes you from good to great.
Lessons from the Pros
Some of the world’s greatest athletes understand the value of sleep and prioritise it as part of their training and recovery:
LeBron James reportedly sleeps 11 to 12 hours per day, combining nighttime sleep with daytime naps. He’s said there’s no better form of recovery than sleep. According to James, quality sleep enables “complete physical and emotional recovery”, ensuring you're ready to perform the following day "at the highest level.”
Roger Federer, the tennis legend, also sleeps 11 to 12 hours daily and credits his consistency and career longevity to prioritising sleep.
If sleep matters that much to two of the best to ever do it, it’s a clear signal for the rest of us.
Make Sleep Your Competitive Edge
In the race to optimise performance, we often look for complex solutions—the latest whatits and whatnots. But sometimes, the simplest answers are the most effective.
Sleep is free, accessible, and scientifically proven to improve physical performance, reduce injury risk, enhance recovery, and sharpen your skills.
If you’re serious about being at your best—whether it’s on the court, in the gym, or just showing up for life—it’s time to give sleep the respect it deserves.
Sleep better. Be better. It’s that simple.
