We all know the importance of sleep. Most of us have heard the startling study which examined average heart attacks after the seasonal time change, finding a 24% increase in heart attacks on the Monday after spring forward (reduced hour of sleep) versus a 21% decrease in heart attacks on the Tuesday after the fall back (increase hour of sleep).1 Sleep deprivation is also linked to chronic health problems like high blood pressure, stroke, obesity, and depression.2 But how does lack of sleep, or even a bad night, impact your performance in the gym and during rehab? The answer is increased pain, spiked effort perception (with same tasks or load), increased injury risk, and delayed tissue repair.
Sleep and pain
After a not-so-good night of sleep, don’t be surprised if pain is exacerbated the next day or even for a few days afterwards. This is especially true if you are recovering from a painful injury or post-op, or have chronic pain to begin with. Sleep deprivation has been found to increase pain perception in both healthy subjects and subjects with chronic pain. According to 2022 systematic review and meta analysis published in Sleep Medicine Reviews looking at 31 studies comparing impact of reduced sleep on pain, they concluded sleep loss increased pain perception3. Disrupted sleep will result in more sensitivity to pain. In a study published last year in the European Journal of Pain, 30 healthy participants, pressure pain threshold was tested before and after 3 nights of disrupted sleep4. They found the disrupted sleep resulted in more sensitivity to pain, despite actual length of time sleeping was not changed. There is a ton of evidence over the past 2 decades studying the complex relationship between pain and sleep. What we do know: sleep and pain are very much related and have a bidirectional relationship, since pain can also affect sleep.
Sleep and performance
After just a single night of impaired sleep (poor quality or quantity), don’t be surprised if you can’t lift as heavy, feel more winded on your usual run or bike ride, and find complex lifts more challenging. Overall exercise performance declines after a bad night of sleep. This mega study analyzed data from 69 publications looking at the effect of acute sleep loss on physical performance measures such as aerobic power, speed, endurance, strength, skill. They found all measures were significantly impacted with acute sleep loss including perceived effort. One interesting finding worth noting, after a night of poor sleep, the earlier you can get your workout in the better. As the day goes on, physical performance only got worse.5,6 In addition to impaired exercise performance and increased perceived effort after sleep loss, it makes a lot of sense that your risk of injury increases as well. A study looking at running related injuries found poor sleep quality as one of the top risk factors for injury.7
Sleep and tissue repair
Sleep is incredibly important for exercise recovery and tissue repair after an injury. Researchers did a study inflicting a small wound on the forearm of participants. Some participants slept their normal 7-9 hours per night. Others decreased their nightly Zs by 2 hours for a 72-hours time period. The participants who got their full night’s rest had a faster healing time than the sleep deprived group (4.2 days vs about 5 days).8 Getting a good night’s sleep will also help with muscle soreness after a hard workout.9
20 Tips to Sleep Better10
Invest in your mattress and bedding
Block out light
Minimize noise
Keep it cool - 65-68 degrees is ideal
Aim for 7-9 hours
Keep bed time and wake times the same every day
Naps are great, but not over 20-minutes
Get into the sleep zone at least 30-minutes before bed (reading helps)
Stay off the electronics at least an hour before bed
Upon waking, get natural light in your eyes (check out Huberman Lab for more info on this)
Exercise daily
Limit caffeine in the afternoon
Don’t drink alcohol (in general, but especially before bed)
Eat dinner a few hours before sleep time
No to smoking anything
Keep the bedroom for only bedroom stuff
When you wake up, get up immediately
Keep a sleep diary if you are testing out new strategies for improved Zs
Supplements help some people
Talk to your medical doctor and/or psychologist if none of this helps
Take-aways:
Bad sleep = more pain and impaired performance
Enough sleep = improved tissue healing times
Aim for 7-9 hours/night
Try out some or all of the recommendations for improved quality and quantity of sleep
Sources:
https://www.franciscanhealth.org/community/blog/daylight-saving-time-heart#:~:text=A%20Michigan%20study%20found%20a,after%20the%20fall%20time%20change.
https://www.nhlbi.nih.gov/health/sleep-deprivation#:~:text=Sleep%20deficiency%20is%20linked%20to,adults%2C%20teens%2C%20and%20children.
https://www.sciencedirect.com/science/article/pii/S1087079222001083
https://link.springer.com/article/10.1007/s40279-022-01706-y#Tab2
https://link.springer.com/article/10.1007/BF02332962#:~:text=During%20the%20walk%2C%20sleep%20loss,loss%20(p%3C0.05).
https://journals.physiology.org/doi/full/10.1152/japplphysiol.00547.2017
https://www.sciencedirect.com/science/article/abs/pii/S1389945723002150
https://www.sleepfoundation.org/sleep-hygiene/healthy-sleep-tips
Photo by Gregory Pappas on Unsplash
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