When we talk about improving sporting performance, we often think of training, diet or energy supplements such as our Baouw energy purees and Baouw gels which you can consume during intense exercise. But there is one factor that is often underestimated and which can make all the difference: sleep. Indeed, getting a good night’s sleep is essential for achieving your goals and performing at your best during endurance events.
The importance of sleep for sporting performance
You’ve no doubt heard this before: sleep isn’t just a break during which your body rests passively. On the contrary, it’s a genuine phase of recovery and optimisation for the body. During this time, the body is busy carrying out a whole host of tasks: it regenerates muscle tissue, replenishes energy reserves, and balances the hormones essential for physical and mental performance…
What’s more, sleep helps to reduce inflammation and oxidative stress – two factors which, if not managed properly, can slow down your progress and increase the risk of injury. Whilst we’re on the subject, let’s take this opportunity to remind you of the benefits of antioxidants for athletes in combating free radicals… ;)
Your body does not rest, it works!
Sleep is therefore far from being a time when everything comes to a standstill. When you sleep, your body carries out a full-scale maintenance programme that you aren’t even aware of. During the night, the micro-tears caused by training are gradually repaired, muscle fibres are rebuilt and new proteins are synthesised to strengthen your muscles. It is also at this time that your body produces more growth hormone, which is essential for tissue recovery, cell renewal and your body’s adaptation to repeated exertion.
Your immune system also takes advantage of this period to recover. An athlete who trains continuously without getting enough sleep becomes more susceptible to infections, which can undo several weeks of preparation.
Finally, your brain doesn’t just sit idle. It clears away some of the metabolic waste that has built up during the day via the glymphatic system. This mechanism is still relatively little understood, but it helps to maintain cognitive function and ensures you feel mentally refreshed when you wake up. In other words, every hour of good-quality sleep is a real investment in the next day’s performance.
The relationship between sleep phases and a successful sports session
Sleep is not a uniform block. It consists of several cycles, each lasting about 90 minutes, which include light sleep, deep sleep, and REM sleep (the one where you dream). Each phase plays a specific role in recovery:
Light sleep: this is a transitional phase that prepares your body to enter deep sleep. It is a time when the body reduces its metabolic activity, but physical recovery has not yet fully begun.
Deep sleep: this phase plays a very important role in physical recovery. It is during this phase that muscles and tissues are repaired, thanks to the release of growth hormone, also known as somatotropin. Deep sleep, which typically occurs one to two hours after falling asleep, is therefore particularly beneficial for endurance athletes.
REM sleep: best known for dreams, it enables your brain to consolidate your muscle memory and helps improve your coordination. In other words, what you’ve learnt during training is better retained, leading to optimal sporting performance. We’ll explain all this in more detail below!
Sleep is therefore directly linked to your performance. In fact, the more demanding your training is, the more sleep your body needs to recover effectively. Endurance athletes, such as marathon runners and cyclists, should therefore regard sleep as an integral part of their training.
Yes, your brain also needs to recover
When we think of recovery, it’s easy to picture our muscles rebuilding themselves after a long run or an interval session. But there’s another part of the body that works incredibly hard during exercise: your nervous system.
During every training session – whether it’s a standard streak running session or work on your basic endurance in preparation for a trail run – your brain controls thousands of muscle contractions, analyses your surroundings, manages your balance, adjusts your pace and makes a multitude of decisions in a fraction of a second. This is all the more true when you’re tackling a night-time trail run, a vertical kilometer or an ironman. The longer or more technical the sessions are, the greater this mental load becomes.
And it is precisely during sleep that your nervous system recovers!
A sufficiently long (and restful) night’s sleep is therefore essential, as it helps to:
improve your concentration,
reduce reaction time,
promote the precision of movements,
enhance coordination,
consolidate the motor skills learned during training.
Whether you are working on your stride, your pedaling technique, or your swimming stroke, part of this progress is built while you sleep.
The consequences of a lack of sleep on your sporting performance
If sleep plays an active role in your sporting performance, does a lack of rest negatively affect the success of your training sessions and competitions? Well, yes, and we can even go so far as to describe the effect as devastating! Indeed, beyond the obvious fatigue, a lack of sleep affects your cognitive abilities, your coordination and, above all, how you manage your energy reserves. Your glycogen stores – the main source of energy used during endurance exercise – decrease drastically, which is obviously detrimental to your training sessions. In practical terms, you feel as though you’ve got the legs but not the head for it.
Sleep and glycogen: a key relationship for athletes
Glycogen is the main fuel for your muscles during exercise. This form of glucose is stored in the muscles and liver, and serves as the main energy reserve for physical activity, particularly during prolonged exercise such as endurance sports. When you exercise, your body draws on these glycogen reserves to fuel your muscles.
However, it is a good night's sleep that enables the body to restore these reserves after intense training, thanks to better absorption and management of carbohydrates. And in endurance sports, glycogen reserves are put to the test... More specifically, carbohydrate metabolism (which includes the synthesis and storage of glycogen) is more efficient during sleep, particularly as part of
Consequently, if you sleep poorly or not enough, your glycogen levels will not be sufficiently replenished. The result is that you start your training session or competition with insufficient energy reserves, and the direct consequence is that your ability to sustain your effort over time is limited. Conversely, if you get enough sleep, this recovery is optimised, allowing you to have energy available again for your next training session.
Lack of sleep, stress, and limited athletic performance
But the impact of sleep deprivation on sporting performance doesn’t stop there! When you don’t get enough sleep, your body raises its levels of cortisol, the well-known stress hormone. Cortisol causes blood glucose levels to rise whilst reducing the body’s ability to store this glucose as glycogen. Put simply, excess cortisol promotes the breakdown of glycogen and doesn’t just slow down its production, which directly affects your body’s ability to store energy for upcoming physical exertion.
These elements explain that lack of sleep limits your ability to perform during prolonged efforts, in addition to increasing premature fatigue.
Sleeping, a preventive action
Sleep, a often forgotten ally against injuries
When it comes to injury prevention, there is a great deal of talk about the importance of warming up, strength training, stretching and gradually increasing the intensity of training. However, sleep certainly deserves a place on this list.
It is now well established that chronic sleep deprivation is linked to an increased risk of injury among athletes. The reason is actually quite logical: when your body doesn’t recover properly, minor dysfunctions build up. Your muscles are more fatigued, your tendons recover less effectively, your coordination suffers and your reaction time slows down. It then becomes easier to land your foot in the wrong place, to absorb impact poorly or to lose precision during a technical manoeuvre. And, as you know, that makes all the difference on the pitch.
Furthermore, fatigue also affects how you perceive exertion. You may feel as though everything is fine, even though your body is already operating in ‘energy-saving’ mode. For those who take part in trail running, mountain biking, ski touring or cycling – sports that require constant vigilance – a delay of just a few tenths of a second can be enough to cause a fall or a collision.
Of course, getting enough sleep obviously does not guarantee that you will never get injured, but it is nonetheless one of the simplest ways to give your body the best conditions to handle training loads over time.
How many hours of sleep are recommended for a high level of sporting performance?
That said, you’re probably wondering what is meant by ‘enough sleep’. There’s no one-size-fits-all answer (that would be too simple!), but scientists who have studied the issue agree on an average of 7 to 9 hours’ sleep per night for an adult. However, for an endurance athlete who puts their body under enormous strain, this recommendation can rise to 10 hours, or even more, during periods of competition or intensive training.
Of course, let’s be honest, just because you sleep for 10 hours a night doesn’t mean your subsequent sporting performance will necessarily see you win your next trail run: when it comes to that, nothing beats the ‘training/sleep/nutrition’ combination!
How can you optimise your sleep to improve your sporting performance?
It's OK to get enough sleep to guarantee a high level of sporting performance! But you still need to be able to fall asleep easily. Here are a few tips to help you fall asleep in the best possible conditions:
Sleep routine: go to bed and get up at regular times to help your body naturally regulate its internal clock. On days off, you can sleep for an extra hour, but do avoid sleeping for 3 hours longer than usual, as this could disrupt your metabolic balance.
Screens before bed: we cannot stress this enough – the blue light emitted by smartphones and computers inhibits the production of melatonin, the sleep hormone. So, it’s better to read a book or practise meditation to help you relax.
A sleep-friendly environment: to help you fall asleep and enjoy a good night’s sleep, we recommend that you sleep in a dark, quiet and cool bedroom. This will help you recover better… and improve your sporting performance the next day!
Eating before bed: depending on the event you’re aiming for, we recommend you read our articles on what to eat before a 10 km run and on the special triathlon diet. Generally speaking, avoid meals that are too heavy or too high in sugar just before going to bed.
Stress management: as stress is the enemy of sleep, it can therefore indirectly affect your sporting performance. Relaxation techniques, such as deep breathing or yoga, are an ideal way to help you calm your mind before going to bed.
Far more than just a period of apparent physical inactivity, sleep is one of the fundamental pillars of sporting performance. By getting enough sleep, you’re giving yourself the best possible chance not only to aid your recovery, but also to optimise your energy reserves and your ability to perform at your very best.
To get the most out of your training and your diet, don’t forget to include sleep in your training plan: it’s the key to pushing your limits and reaching new heights!