Sleeping in the heat is notoriously difficult. Heat can disrupt even the best sleepers, not least since core body temperature must drop to initiate sleep. This reduction in the ability to reduce core temperature means many of us are struggling to get to sleep in the first place at the moment. One of our Environmental Extremes Lab PhD students, Julie Gooderick, whose PhD is focusing on sleep hygiene gives us a few simple tips which may help you improve your own sleep hygiene as we move towards the peak of the heat wave.
8 Top Tips for Sleeping in the Heat
1. Set your environment
The ideal room temperature for sleeping is around 18-21°C. Open your windows, make use of fans or A/C to facilitate this. Prevent your room becoming too hot in the day by keeping curtains drawn to block out the sun; then there’s less work to do to reduce room temperature of an evening. At night, open your windows to let hot air out and cooler air in.
2. Consistency is key
Sleep regularity (going to bed and waking up at the same time each day) is a key factor in improving sleep quality and duration. Keep to your usual routines; try and go to bed at the same time as you usually do, rather than being tempted to stay up and wait until it feels cooler.
3. Use thin sheets and bedding
Using a thin sheet instead of your usual duvet has the benefit of helping to absorb sweat, but also offers some protection against feeling colder in the early hours of the morning. When struggling to fall asleep due to heat, it can be tempting to ditch the covers altogether, but in instances where it takes longer to fall asleep, the last thing you want is to be waking feeling cold around 3am!
4. Consider what you are drinking during the day
It is common for alcohol consumption to rise during heatwaves. Alcohol acts as a sedative, meaning the time taken to fall asleep after consumption is often reduced. However, in the hours following this, sleep quality is reduced, with a significant reduction in deep sleep and more awakenings likely. Reduce alcohol intake in the evenings to maximise sleep. With regards to general hydration, ensure your water intake is spread throughout the day, rather than being concentrated in the evenings. You are likely to be drinking more in the heat which is great – but last thing you want is to be waking up to use the toilet in the night during a time when sleep is already more disturbed than usual.
5. If you can’t sleep, try a non-stimulating activity
If you can’t sleep, the temptation to reach for your phone is high! In this situation, avoid blue-light exposure or psychologically stimulating activities, like TV, gaming or online shopping. Reading, meditation or gentle stretching are all good things to do to relax and reset the mind before attempting to sleep again.
6. Avoid napping in the day
Hot weather commonly makes us feel drowsy, in part because we are using more energy to regulate our body temperature. So it’s tempting to have a daytime nap to offset the tiredness. However, building up sleep pressure throughout the day is likely to have the benefit of making it easier to fall asleep in the evening, regardless of environmental conditions. If you simply can’t manage without a nap, keep it to 10 minutes only, and take it in the early afternoon – this has been shown to give minimal interference with night-time sleep.
7. Cool your body
Incorporating some form of cooling into your nighttime routine is another way to help your sleep as it may delay or even prevent a rise in sweating. Reducing the chances of sweat-drenched bed sheets will also prevent you getting dehydrated. There are cooling pads and pillow cases on the market that can provide a form of cooling therapy, but there are plenty homemade options that can work too. You may decide to take a cold instead of a hot water bottle to bed, or put what you plan to wear in bed in the fridge or freezer a few hours before going to bed. Some evidence suggests a cool shower before bed can help sleep onset.
8. Finally…. relax!
It is important to remember that heatwaves are short occurrences in the UK. Even if your sleep duration is compromised during this week, increasing sleep in the subsequent few days after the heatwave – “recovery sleeping”- can go some way to boosting mood, increasing daytime alertness and reducing disease susceptibility.