Physically tiring yourself out may seem like a logical way to get a good night’s sleep, but exercising too close to bedtime could have the opposite effect.

“Strenuous workouts can stimulate the body and increase our temperature, which can make it difficult to nod off,” explains Alasdair Henry PhD, research manager at Sleepio, an NHS-approved digital sleep-improvement programme. 

We should avoid intense exercise two hours before bedtime to get the best night’s rest, he says. “A drop in body temperature is an important cue for sleep, so counteracting this process with exercise may keep you awake,” he tells HuffPost UK. 

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While there is limited research into how exercise affects sleep the few studies in this area do show working out can help improve sleep, says Henry – providing you do it at the right time of day. “Moderate aerobic exercise can help you fall asleep faster, improve sleep efficiency and sleep quality, and also make you feel more rested in the morning,” he says. 

Although the reasons for these effects are unclear, the benefits are thought to be due to a drop in the body’s temperature in the hours after exercise – which may make it easier to sleep. Exercise can also help improve our mood and reduce feelings of anxiety, Henry adds. 

It makes no difference whether we workout in the early morning or afternoon, the research shows – it’s only working out immediately before bed that can be troublesome. If you already work out later in the evening, however, and haven’t found that it affects your sleep, then there’s no need to change your routine. 

But it’s not just a one-way relationship between sleep and exercise. Personal trainer Dom Thorpe argues that just as exercise can potentially improve sleep, so sleep can also improve how we experience exercise. “Exercising requires recovery time, which is best done when asleep,” he tells HuffPost UK. 

In order to reap the biggest benefit from sleep, Thorpe says you should keep your workouts varied. It’s important to cover the three main types of exercise –cardiovascular, resistance (strength) and flexibility (yoga or similar) – he advises. 

Thorpe agrees with Henry that in an ideal world, we would “train, eat and sleep in that order”, but points out modern life doesn’t always allow us to stick to this routine. “As an alternative, a great way to lead you into a deep sleep would be to do a relaxing form of yoga such as Yin shortly before bed,” he says.