I know from personal experience that sleep is a powerful recovery aid and predictor of athletic performance. Optimal recovery, which is influenced by sleep quality, is critical to tissue repair, metabolism and cognitive function, all of which contribute to work capacity. Athletes who want to see results from their training know that proper recovery from training stress is essential for improving performance.
That’s where cold, hard data, like Polar Ignite’s Nightly Recharge numbers, can help you figure out your optimal nutrition for sleep.
In addition to lifestyle factors, nutrition has a considerable impact on how well we sleep but, as every person’s physiology is unique, it’s not that simple to define generic guidelines on what to eat before bed.
Here’s how what you eat during the day and before bed can impact your sleep, and why that is crucial to your recovery and performance.
WHY QUALITY SLEEP IS ESSENTIAL FOR RECOVERY
Sleep is easily one of the most overlooked factors in an athlete’s training program, but getting enough of it is essential to performance in sport and in the demands of daily life. Most of us have heard general guidelines for sleep (get 7-9 hours of sleep per night, limit screen time in the evenings, prioritize sleep), but few of us really make an effort to follow through. It turns out that’s to our detriment.
Poor sleep is linked to increased stress response and inflammation, lower immunity, irregular patterns of hunger hormones like leptin and ghrelin, lower glucose tolerance, and decreased insulin sensitivity.
For athletes, this means that carbohydrate metabolism and protein synthesis are affected. The result is a reduction in glycogen availability (the primary fuel for higher-intensity exercise), lower muscle-building potential and less training adaptation overall.
A bad night’s sleep also means inefficient recovery of the autonomic nervous system (ANS), lower heart rate variability during sleep and a higher resting heart rate. Athletes in particular also suffer from increased inflammation as a result of oxidative stress brought on by intense training sessions and are at greater risk of injury
HOW OPTIMAL RECOVERY CONTRIBUTES TO PERFORMANCE
The good news is that working to improve our sleep can actually undo a lot of the damage we incur in training and sport.
All of these improvements also have a direct impact on sport performance and adaptation.
Just improving the quality and duration of sleep patterns has been shown to restore immune system and endocrine function, improve recovery of the nervous system, reduce inflammation, sharpen memory and increase learning capacity. In short, effective sleep is directly tied to athletic recovery.
To name some of the performance benefits athletes derive from a good night’s sleep:
- Muscle growth
- Efficient use of fuel
- Increased intensity
- Improved reaction time
HOW NUTRITION IMPACTS OUR SLEEP
So, what can we do to maximize our sleep quality?
There are a number of lifestyle factors that impact the quality and quantity of your sleep, like maintaining a consistent bedtime and reducing exposure to light in the evening, but implementing nutritional changes can influence our sleep as well, for good or bad.
I tested out some nutritional changes myself and found the results astonishing.
1. ALCOHOL AND LATE-NIGHT SNACKS? THAT’S A NO FROM ME.
Some foods have been shown to negatively impact sleep.
For example, there are strong links between daily caffeine consumption and disruption of sleep onset, lower sleep duration, and poor perceived sleep quality.
While I didn’t notice a big difference in curtailing my caffeine intake, any time I drank alcohol the amount of REM sleep I got (key for memory, learning and protein synthesis) was far lower and I woke up frequently throughout the night, which is no surprise. Eating late at night too made it hard for me to fall asleep quickly. None of this is ideal for recovery.
2. VITAMINS AND PROTEIN GOING THROUGH TO THE NEXT ROUND
On the other hand, improving your nutrition has the ability to give you better sleep and recovery.
I prioritized a diet rich in fruits and vegetables containing micronutrients including Vitamins A, C, and E. Getting these vitamins from whole food sources (not supplements) imparts a lot of antioxidant benefits, reduces oxidative stress, increases immunity and improves post-exercise recovery.
Additionally, I ate more protein sources rich in tryptophan (like dairy, turkey, fish, eggs, seeds and beans) which allow the brain to produce serotonin, and eventually melatonin, leading to improved sleep and longer sleep duration.
3. TARGETED CHANGES TO WHAT TO EAT BEFORE BED
I also made more targeted changes to my diet to improve sleep. One of these changes was consuming some higher glycemic index carbohydrate meals a couple of hours before bed. These have been shown to help people fall asleep more quickly, increase REM sleep and decrease light sleep.
Consuming tart cherry juice (which contains melatonin) is something else I did just before bed. It has also shown to increase sleep duration, sleep efficiency and reduce inflammation and markers for insomnia. It has the added bonus of reducing delayed-onset muscle soreness, or DOMS, and inflammatory response post-training in marathoners.
I cannot be certain that it had a direct impact, but seven days into this practice and my sleep was remarkably improved. Kiwifruit is another example of a food I will be adding to my diet; the combination of micronutrients it contains appears to be beneficial in extending quality sleep.
4. HOW NUTRITION CHANGES AFFECTED MY SLEEP
After four weeks of experimenting, I can confidently say that my sleep is getting better every night. I also feel like I have the tools and knowledge to get a good night’s sleep.
While incorporating these nutritional practices has been shown to have a beneficial effect in studies, every single body is unique.
My results gave me some fantastic information about myself, but the studies I reviewed have their limitations (including gender and age biases, sample size and attrition).
Unfortunately, there’s no one-size-fits-all when it comes to nutrition, and that’s where a knowledge of your own body and tracking personal data can help. The Nightly Recharge feature on the Polar Ignite can give you strong indications of whether changes to your nutrition are working for you, just like they did for me.
Specifically, what you should look for are shorter sleep interruption periods, longer sleep duration, increased heart rate variability and a better ANS and Sleep score. Over time, you may also notice a lower resting heart rate.
TIPS FOR RECOVERY FOODS THAT SHOULD IMPROVE SLEEP QUALITY
There are practical nutrition changes you can test out to improve your sleep, thus maximizing recovery and subsequent performance. As with any nutritional changes, it’s best to check with your doctor beforehand.
If you do incorporate any of the following suggestions, try tracking changes in your sleep patterns.
WHAT TO EAT BEFORE BED?
- Give yourself 2-3 hours to digest larger meals before bed; eating larger meals later means your digestive system has to work harder, making it more difficult to fall asleep.
- Consume a meal rich in high-GI carbohydrates about 4 hours before bedtime; think about including foods like potatoes, breads, pasta and rice at that time.
- Ensure you’re getting lots of micronutrients like Vitamins A, C and E from whole food sources throughout the day; that means prioritizing a wide variety of fruits and vegetables in your diet, which can help lower oxidative stress and improve sleep and recovery.
- Eat tryptophan-rich proteins alongside a carbohydrate-rich dinner to help your body produce melatonin, improving sleep quality; opt for good sources of tryptophan like dairy products, seeds, eggs, turkey, fish, pumpkin and beans.
- Improve your sleep quality and quantity by having specific foods like kiwifruit and tart cherry juice before bed (look for unsweetened versions, and try doses of 30-60ml before bed).
Getting your nutrition right is one way to set yourself up for better sleep and recovery so I, for one, will definitely prioritize reducing alcohol, drinking tart cherry juice and eating plenty of fruits and vegetables daily.