The Sleep-Exercise Connection Explained

The feeling of waking up after a good night’s sleep is superb. You feel ready to take on the day and put your best self out there. If only every morning could be like that! Read on to find out about how exercise could be the thing that takes your sleep to the next level…

Exercise. Yep, I know, can that really help my sleep? Maybe you were hoping I would offer a magical answer and then your sleep would be sorted forever. On the plus side exercise is (potentially) free, can be tried in a myriad of forms and, as you know, also has many other benefits.

I’m Dr Kate Ella. A health coach, doctor and qualified gym instructor. I think sleep is still under-rated as a key component of health and the more that I have learned the more I have confirmed that view. I love sleep and I love exercise so discovering that they act synergistically was a pleasant realisation.

Sleep is clearly immensely important to our functioning. Yet, it remains mysterious. We know that sleep has phases. We know that sleep disruption is associated with many chronic conditions. But there is still so much we don’t know. To my knowledge no-one has definitively answered the question of our childhood: why do we dream?

Despite that, there is some consensus amongst experts as to what improves and what worsens our sleep. Exercise is one of those improvers (as you had probably guessed given the intro). In his book, Why We Sleep, Matthew Walker puts it as number 2 in his list of tips for healthy sleep.

How does exercise help your sleep?

One potential mechanism is through its link with deeper sleep. It appears that daytime exercise can increase the time spent in slow wave sleep (deep sleep) which is thought to be the most restorative phase of sleep. Interestingly this does take a little time to occur so don’t worry if you don’t feel the benefits on your sleep immediately. A study of 67 women found that the significant improvement in sleep was only seen after 4 weeks of regular aerobic activity.

Another hypothesis is that exercise may increase brain-derived neurotrophic factor (BDNF). A very long word but a molecule that we are becoming increasingly aware of. Exercise appears to increase the blood concentration of BDNF which has been shown to increase the depth of sleep. Interestingly higher levels of BDNF have also been associated with reduced rates of dementia which may be another link in the puzzle.

Can sleep help your exercise goals too?

If you want to get a 5km PB in the parkrun or make it up a Munro on a hill walk can sleep help? I was certainly brought up to think so. As a teenager my running coach was keen to ensure that I understood that good sleep in the days before a race was a key part of my preparation (I can’t pretend that I always listened!). Some interesting research has found that this really is true. The effect of sleep on next day exercise was even greater than the effect of exercise on sleep. Andy was right!

Balance

It is important to keep perspective though. If you decide to exercise with the sole aim of improving your sleep or if you decide to prioritise your sleep mainly to improve your 5km PB then it might not have the effect you desire. Dr Guy Meadows writes in his book, The Sleep Book, How to Sleep Well Every Night:

As with many lifestyle habits, the key point here is your intention. If you are exercising because it is an enjoyable, healthy thing to do, then it can have a positive impact on your sleep. However, if you are doing it with the intention of getting to sleep, you run the risk of placing yet more unwanted pressure and anxiety on yourself and inadvertently pushing sleep further away.

Dr Guy Meadows in The Sleep Book

What should I do?

If you do want to give this a try what can you do? Well exercise is the first part. Some people do worry about the timings. There is evidence that exercise can train the circadian rhythm. And, in some individuals exercise in the hour or two before bed, particularly if intense can delay sleep. In his book, Life Time, Professor Russell Foster discusses that this is likely due to the increase in core temperature that occurs with vigorous exercise. Moderate aerobic exercise has the most positive results in the research. So a speedy walk or game of tennis in the morning is the probably the optimal but it has to be something that you want to do regularly!

How can I help?

I can work with you to create a personalised plan to transform your lifestyle and optimise your health including your sleep and exercise. Drop me an email health@drkateella.co.uk. I’d love to hear from you and see how I can help.