Trouble sleeping despite exercise – or because of it?

22. July 2020

Around a quarter of people in Switzerland suffer with sleep disorders. What impact does this have on exercise – and vice versa?

Exercise and sleep are closely linked. To get the full benefit from a workout, the body needs sleep to recover. And, conversely, you’ll only have enough energy for your next workout if you’ve had enough sleep.

But not everyone starts the morning feeling refreshed and raring to go. Katharina Stingelin, a human biologist and sleep specialist based at the sleep therapy centre KSM Bad Zurzach, estimates that around 20 percent of people suffer from insomnia (which refers to difficulties with falling or staying asleep, or waking early). In total, there are around 80 types of sleep disorder, divided into eight subcategories.

The massive impact of sleep disorders on people’s physical and mental health becomes clear when you consider the many functions that scientists ascribe to sleep. These functions aren’t yet fully understood, but it’s clear that the body is anything but inactive at night. During sleep, cells are regenerated, the immune system is boosted, hormones are released and memories are formed.

Exercise affects sleep …

Generally speaking, physically active people are less likely to suffer from sleep disorders. Katharina points out that “active” doesn’t necessarily mean doing sport. She encourages her patients to do regular exercise to help them manage their sleep disorders, and it doesn’t matter whether that’s hard-core running or just a walk in the fresh air. The important thing is: “If you do sport, you shouldn’t do it too close to going to bed. Doing sport in the evening is OK, but the body needs a few hours to calm down and reduce adrenaline levels after intensive exercise.”

For this reason, Katharina recommends doing more relaxed endurance exercise in the evening that doesn’t get the pulse racing. But if you do an evening training session once a week (for instance at a sports club) and can’t sleep afterwards, it doesn’t necessarily mean you have a sleep disorder: “That’s perfectly normal, and has a clear cause.”

Most people’s peak performance is at around ten in the morning. The body has higher levels of testosterone in the morning, meaning more energy to build muscles. So it’s worth working out before noon if you can, allowing for personal factors like work or getting children to school. Ideally, you should take a midday nap after the morning workout, though that’s not possible for most people with jobs.

24-hour gyms are handy for people who wouldn’t otherwise be able to get to the gym (for instance because they work shifts), but Katharina points out that “muscle training in the middle of the night is unnatural for human beings”.

In high-level athletes, sleep disorders can be a sign of overtraining. But mental factors can also play a role. A survey by the Swiss Federal Office of Sport found that a third of Swiss athletes at the 2014 Winter Olympics in Sochi had difficulties falling or staying asleep.

… and vice versa

Getting enough sleep is essential to achieve top sporting performance, while chronic lack of sleep is a performance killer. Over half of people with sleep disorders have low levels of energy and vitality. Lack of sleep also significantly increases susceptibility to injury when doing sport.

According to Katharina, the occasional night of poor or minimal sleep (for instance, if you get nerves on the eve of a competition) has little impact on sporting performance. But long-term sleep disorders do make it very hard to train and work out. “Affected patients are normally so de-energised that they can’t even think of exercise.”

It’s difficult to say how much exercise a body can manage without sleep, but it’s rare for someone not to sleep at all. “Often people feel like they’ve not had a wink of sleep all night, but they’re usually mistaken.” Still, for the sake of your body, if you’re doing a lot of exercise and having trouble sleeping, you should definitely try to sort it out before you start thinking about intensive training again.