I’ve done enough long runs now to know I don’t sleep well the night after a long one, but I’m still surprised when I wake up time after time AFTER TIME during the night. What is wrong with me? I should be exhausted. Why won’t my body let me sleep? As a coach, I know that sleep is crucial to recovery, so it’s very frustrating laying there in a dark room counting sheep and willing myself back to sleep.

I posed this question to Twitter and it turns out that I am overwhelmingly not alone in this, yet an internet search provided no scientific studies into why this is the case, just a bunch of forum questions and (very unscientific) replies so I’ve collated some theories here:

  • Post-run adrenoceptors in your body can have the same effect as caffeine in keeping you awake. It has been suggested that doing long runs early in the day can lessen this effect. Hard running can also increase the stress hormone cortisol, giving you that anxious feeling which makes it difficult to sleep, so save speedwork for mornings rather than late in the evening. If you must run in the evening, try to schedule your run so you finish at least 3 hours before going to bed.
  • If you’ve taken caffeine on during a run, this can stay in your system for up to 14 hours. A good tip is to avoid any caffeine after midday to prevent this affecting your sleep.
  • Your mind may be working overtime thinking about the run, especially if it went especially well or badly. This can be linked to anxiety, which raises our cortisol levels and prevents us sleeping.
  • Aches and pains and sometimes restless leg syndrome can play a part in causing discomfort and hence disturbing sleep.
  • Dehydration after particularly long runs can lead to insomnia and an increased heart rate as cortisol levels flood your body. Staying well hydrated can blunt this response. Rehydrate sensibly during and after running, but try to avoid taking on fluids two hours before bedtime as a full bladder will also interfere with sleep.
  • Low blood sugar can lead to a lack of deep, consistent sleep. When your blood sugar drops below a certain level, cortisol is released and a surge in adrenaline forces you to wake up. Low blood sugar levels will keep your body in a catabolic state throughout the night, instead of the anabolic process that is critical to repairing muscle damage incurred through training. Typically if I’ve had a long run, I tend to consume most calories in the days afterwards. Whilst we tend to focus on protein replenishment, carbs are especially useful to replace, and will help you sleep. It is generally advised not to eat too much before going to bed, as then digestive processes will interfere with natural sleep patterns. Bananas are a good evening snack because they contain chemicals to help with the natural onset of sleep. Cottage cheese or another easily digestible protein (such as a protein shake) may also be helpful in regulating blood sugar levels.
  • For those who run later in the day, your core temperature may still be too high. A trick to reduce this quickly is to take a warm bath an hour or so before bed, to encourage your temperature to drop afterwards to induce sleepiness.
  • Deficiencies in certain vitamins and minerals, such as iron, zinc and magnesium, can also play a part in sleep disturbance. Speak to your GP about some simple blood tests which can check these.

If you are experiencing regular sleep issues, this may be an indicator of overreaching or overtraining, and may be your cue to take some extra recovery time. If you are also suffering from anxiety or depression then this may also affect your sleep habits. Do you experience issues sleeping after running? I’d love to hear any tips you have for getting a better night’s sleep.

This article is not intended to provide any medical advice. Please consult your healthcare professional if you are experiencing regular insomnia, or are worried about any other sleep-related issues.