By James Kennedy.
Sleep. A health and performance essential that everyone loves. Yet, according to the ONS, nearly half of UK adults report not getting enough sleep, with a quarter surviving on less than 5 hours a night. The same survey found that despite people recognizing they have a problem with inadequate sleep, less than half of poor sleepers are actively trying to improve their sleep.
Within this guide, we will explore why we need to sleep and the special importance of sleep for strength and physique athletes. We will then explore how much sleep you need and whether catching up on sleep works as effectively as getting enough sleep every night. Finally, we will outline how to set up a bedtime routine to improve the quality and quantity of your sleep.
Why do we need to sleep?
Everyone needs to sleep. Getting adequate sleep is linked to better mood, better focus and better performance in every aspect of life. For strength athletes, who spend hours in the gym trying to maximise muscular hypertrophy and strength gains, sleep is even more important.
Sleep is a key factor in boosting recovery from training and maximizing muscle protein synthesis (MPS) i.e. muscle growth. Without adequate sleep, your body does not have the opportunity to recover fully from training, leaving you unable to perform maximally in subsequent training sessions and in competition.
For the bodybuilders, physique focused and powerlifters trying to move down a weight class for those sweet, sweet wilks gains, sleep is just as important for physique results.
Chronically under-sleeping is linked to higher body fat levels (1) due to a combination of altering hormone levels and limiting diet adherence. Studies have found that when people are systematically under sleeping, they eat an average of 350 extra calories per day vs a control group getting adequate sleep (2). This equates to an extra 2450 calories a week. To put that in perspective, the recommended daily caloric intake for a sedentary man is 2500 calories. Eating an additional 2450 calories a week equates to almost a whole extra day of eating per week, making weight loss even more challenging.
A lack of sleep also alters the hormone balance of the body. Being in a sleep deficit reduces the level of two anabolic hormones within the body - specifically testosterone and IGF-1 - hormones critical in muscle protein synthesis (3). The same research shows that a lack of sleep leads to a rise in cortisol levels - a catabolic hormone which increases rates of muscle breakdown. These mechanisms - overeating, a reduction in anabolic hormones and increase in catabolic hormones - all combine to hinder recovery, reduce lean body mass and slow weight loss.
Another consideration for strength athletes is injury risk. Multiple studies (10, 11) have investigated the link between under sleeping and injury risk. The findings are predictable: the amount of sleep an athlete gets is the biggest predictor of injury risk (10) and getting less than 6 hours sleep increases injury risk from the very next day (11). This is due to the combination of a decrease in coordination when tired and the reduced ability of the body to recover from previous training.
How much sleep do you need?
The standard recommendation for adults is for 7-9 hours of sleep a night, with some people needing more and some needing less. In all likelihood, as life happens you’ll find yourself needing more or less sleep at different times. Generally however, if you’re waking up tired or need a lot of caffeine to get moving in the morning then you need to sleep more.
A key distinction needs to be made however, between hours asleep and hours in bed. If you get into bed at 10pm then spend 3 hours scrolling through social media before drifting off at 1am and waking up at 7am feeling tired - you're not ’sleeping nine hours and still tired’. If you feel as though you need more sleep, make sure you're actually sleeping for 7-9 hours a night.
Can you catch up on sleep?
A common response to being tired during the week is to have a ‘lie-in’ over the weekend to catch up on sleep. Is this a good idea and does it work?
If the average adult needs at least 49 hours sleep a week (7 hours a night), the number of hours under this number is known as their sleep deficit or sleep debt. For example, if you slept 6 hours a night from Sunday to Thursday night with a sleep debt of 5 hours. The intuitive response to this is to get an additional 3 hours of sleep on Friday and Saturday night to make up the sleep debt. But does this work?
Maybe. It is possible to catch up on sleep - with studies highlighting that sleeping in on the weekend is linked with improved insulin sensitivity, fat metabolism, body weight, stress, fatigue and performance (12-16). Sounds good right?
The downside of this approach is that sleep debt - much like credit cards or student loans- accrues interest at an unholy rate. Getting one extra hour of sleep at the weekend does not compensate for an hour of lost sleep - instead the ratio is closer to 1:4 (17). For every hour you under sleep during the week an additional 4 hours are required at the weekend. Going back to our example at the top, the person with 5 hours of sleep debt heading into the weekend needs 20 hours extra sleep to catch up.
There are more downsides. By sleeping in on the weekend, you disrupt the bodies circadian rhythms, making it harder to sleep during the week and increasing your sleep debt.
Napping may provide an alternative - short, 30 minute naps, improve performance in the short term and longer naps (up to 1 hour) allow for muscle repair (18). However, napping can make it more difficult to sleep in the evening - leaving you unable to get enough sleep at night.
What are we to do with this information? Well, if you haven’t had enough sleep during the week, sleeping in on the weekend will help you feel better and may alleviate and offset some of the problems associated with under sleeping. The best plan however, is to avoid being in a sleep deficit at all.
How can you maximize muscle growth during sleep?
Sleep enables recovery and growth, as it is the period of the day where the body heals and your muscles grow. Studies have shown consumption of a protein shake before bed leads to increases in overnight MPS and subsequent muscle hypertrophy (6). This effect is observed even when the participants are consuming a high protein diet (1.3g/kg of protein/bodyweight) (7) and is independent of an increase in total calories (8). This strong body of scientific literature led the International Society for Sports Nutrition to recommend the consumption of 30-40g of protein before bed, as doing so acutely increases muscle protein synthesis and metabolic rate through the night (5). Further, consumption of a small meal before bed has been linked to improvement in sleep quality (9), which will enable further muscle growth by maximising the time your body has to repair and growth - win-win!
It is often claimed by supplement companies that you need special nighttime protein that breaks down slowly whilst you sleep. This is just an excuse to sell you casein protein. Whilst supplement companies advertise that casein - a more expensive product - is the only suitable overnight protein, multiple studies have found that whey protein is superior to both casein and soy protein for maximising muscle protein synthesis (3,4).
Now we have established why we need to sleep and how much we need to sleep, how do we set up a routine for us to get a good nights sleep every night?
1. Allow enough time to get enough sleep.
This might sound obvious, but if you want 7 - 9 hours sleep and have to wake up at 6am then you need to be asleep between 9 - 11 pm.
2. Establish a wind down routine
It’s important to take some time before you got to sleep to relax and get you ready for sleep. This can take anywhere from 20 - 45 minutes, depending on how stressful your day has been. Reading a book, doing yoga or stretching, meditating, journaling or planning out tomorrow are all good activities to do during your wind down routine.
During this time, the key point is to avoid activities that stimulate you or your brain, making it harder to drift off and sleep well. Try to avoid phone, tablet or laptop screens - blue light exposure reduces melatonin release which makes it harder to fall asleep. If you are going to use a phone, download an app that uses a blue light filter.
3. Stick to a schedule
Once you have established a bedtime routine and a wake-up time that enables you to get enough sleep, stick to it. Even over weekends. Allowing your body to go to sleep and wake up at the same time every day allows for the establishment of a strong circadian rhythm. After a while, you’ll begin to feel tired when it’s time to start the bedtime routine and alert when you wake up. Use your body’s natural rhythms to your advantage and you’ll sleep better!
Daily exercise helps you sleep more deeply. This doesn’t mean you have to hit the gym every day - even going for a walk during the day can help improve your sleep quality.
5. Be careful with caffeine
Caffeine is a stimulant - this is why we like it. It’s primary role is to increase awareness. Avoiding caffeine around bedtime will massively help improve sleep quality. Caffeine has a half life in the body of 6 hours - avoiding caffeine in the 6 hours before bed will allow you to drift off quicker and sleep deeper.
6. Improve your sleep environment
The sleep environment (i.e. a bedroom - hopefully), is a key component of getting a good nights sleep. It should be cool dark and quiet. Ideally, utilise black out blinds or sleep masks to reduce the amount unnatural light pollution from outdoors (street lights, car lights etc) . If your bedroom is noisy, utilise ear plugs or a sleep soundscape to block out external noises which can stop you drifting off to sleep.
1. Sleep is an important part of the recovery process; getting adequate sleep will help improve body composition, strength gains, mood, mental performance, recovery and reduces injury risk.
2. Adults need 7 - 9 hours of sleep a night. Setting a consistent bedtime and a wind down routine will allow your body to settle into a rhythm.
3. Catching up on sleep is not a viable long term strategy. Catch up sleep is lower quality and can prevent you establishing a healthy sleep routine. Napping (in the short term) and establishing a bedtime routine is essential to maximise the benefits of sleep and reap the rewards from training!