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by Steph Saullo RDN

October 16, 2017

A good night’s rest is important to your health and athletic performance

Sleep and athletic performance go hand in hand. Inadequate sleep can impede your performance in the pool and, over time, can damage your health.

During sleep, the body receives the opportunity to not only build new tissue but repair muscle. A restful night will also uphold the body’s ability to restore muscle glycogen (the body’s storage form of carbohydrates).

When the body is deprived of sleep, levels of cortisol (a stress hormone) increase and this may cause the body to break down lean tissue (i.e., muscle). Lack of sleep can negatively impact your metabolic rate, hormones that regulate body fat, and your appetite. Your immune system may be compromised.

In 1989, the Guinness World Records, in fact, removed the record for longest time without sleep—a reported 11.5 days (or 276 hours)—to deter attempting to set a record harmful to health.

Ample sleep is also required for the development of new skills and optimal neurocognitive performance, which is important for attention, reaction, and decision making. Poor reaction and inattention may increase your risk for injury. For most adults, seven to nine hours of restful sleep in a 24-hour period is ideal. If you’re doing a lot of hard training, you may require more.

Here are some things to keep in mind to make the most of your sleep.

Nighttime Noshes

There is no one food or nutrient that will magically improve your sleep, but there are some ingredients that are involved in regulating sleep processes and some that may enhance sleep.

Adequate Calories

Without consuming enough fuel, you will not swim your best, and your sleep likely won’t come out on top either. Some research suggests that the composition of the diet may influence sleep more than calories alone. Furthermore, research suggests that the timing and composition of meals (e.g., high glycemic index carbohydrates versus low glycemic index carbohydrates to influence the levels of serotonin) may impact the quality and quantity of sleep.

If you’re having trouble falling asleep try a bedtime snack, but keep it small with a little bit of both carbohydrates and protein. While you may feel sleepy after eating a large meal, being overly stuffed can make it difficult to fall asleep and may interrupt sleep. Try half of a peanut butter sandwich, cereal with milk, or a fruited Greek yogurt.


During sleep, the body undergoes a period of growth, repair, and recovery. While the intake of protein won’t likely improve sleep on its own, it is worth noting that protein intake before bedtime has its own set of benefits, specifically for athletes. It has been well established that protein intake is important for maintaining lean tissue and muscle protein synthesis. Research further supports protein intake for post-exercise muscle growth during overnight sleep, its response to training, and improvement to exercise training efficiency.

Adequate protein from any protein source will support this effort; however, casein, a protein found in milk, is digested slowly compared to other sources of protein and can act as a steady supply of protein for muscle growth and maintenance.


You’ve probably succumbed to a nap after eating Thanksgiving dinner. That may be attributed to an essential amino acid called tryptophan that is found in turkey and other foods with protein. Tryptophan is also the reason some people reach for a glass of warm milk before bed. Besides milk and turkey, tryptophan is found in other sources of poultry, meat, fish, eggs, beans, peanuts, cheese, and leafy greens.

Tryptophan is converted to serotonin which is turned into melatonin, a hormone that affects circadian rhythms. It has also been suggested to consume foods with tryptophan with carbohydrates to help enhance the effects of tryptophan on sleep. Research suggests that eating tryptophan may help reduce the length of time it takes to move from being fully awake to asleep.


You may believe that having a drink or two before bed is a great way to relax and alcohol may help you to fall asleep faster. Research, on the other hand, shows that alcohol can cause adverse effects to sleep quantity and quality. To avoid disrupting sleep, it is best to avoid alcohol before bed.


Caffeine is a stimulant that may be helpful for an early-morning practice, but does just the opposite for us at night. Caffeine increases our awareness and may lengthen the amount of time required for you to fall asleep, shorten sleep duration, and negatively impact the quality of your sleep.

The half-life of caffeine is about six hours, meaning half of the original amount of caffeine ingested remains within the body after six hours. While individual tolerances and responses will vary, it is recommended that caffeine be avoided in the late afternoon/evening hours or at least six hours before bedtime.

Common sources of caffeine include coffee, tea, cola, chocolate, energy drinks, and any supplements that contain guarana (guarana contains caffeine). Some over-the-counter and prescription medications (like those for pain and colds) also contain caffeine, so be sure to check the ingredient list.


Getting plenty of water and staying hydrated is key to performing your best. Unfortunately, drinking too much liquid or taking in liquid too close to bedtime results in waking up to use the bathroom during the night thereby cutting your dreams short. It is important to drink adequate fluid throughout the day and to rehydrate after a training session or event. If you find that you wake a few times during the night hours to void, consider adjusting your training and/or hydration tactics if possible.

Tips for Better Sleep

  • Make sleep a priority. Don’t skip sleep. Although you may be able to get by on less sleep for brief periods, sleep debt will accumulate. Just like credit card debt, it doesn’t go away. Eventually it will need to be repaid by sleeping longer.
  • Give yourself enough time to sleep. Remember it takes time to fall asleep, so if you have a target number of hours in mind, don’t assume you’ll doze off the moment your head hits the pillow.
  • Create an environment that supports quality sleep.

»       Make it dark. Less light helps the body know that it is time to sleep.

»       Keep it quiet. A noise machine or white noise is also acceptable.

»       Turn off/avoid blue lights. Electronics like the television, computers, phones, and tablets, and even LED lightbulbs disrupt your body’s sleep-wake cycles. Although light in general suppresses the release of melatonin, blue lights seem to have an even greater effect. It has been recommended to steer clear of blue lights two to three hours before bed.

  • Stay active. If you are training great, just be conscious not to overtrain. Unfortunately, early-morning training does not help when it comes to obtaining adequate sleep.
  • Be consistent. The timing of your sleep is important, but maintaining regularity when it comes to when you hit the hay is even more so.
  • Relax. Develop a routine that is relaxing and avoid stressful situations or discussions before turning in.


  • Health and Nutrition


  • Recovery
  • Sleep