One of the most easily overlooked aspects of injury recovery and general well-being is sleep. I recently finished the book Why We Sleep by Matthew Walker on a recommendation and due to the fact that I have had my own struggles with sleep. It is odd that something that we are supposed to do for one third of our lives was never really talked about in chiropractic school scientifically and how it relates to health and performance. This book really helped bridge those gaps by citing numerous studies, and in this blog I will detail some of the highlights I found to be interesting as a chiropractor and baseball coach to help shed some light on this mysterious state we call sleep.
In the United States there is this idea that somehow the less sleep you get, the more successful you are because you are too busy to sleep. It almost seems to be a rite of passage once we enter the workforce. Research shows that this is a terrible trap to fall in to and in some cases, a fatal one. In the U.S., the average amount of sleep has decreased over the last 50 years bringing the average amount of sleep to just under 7 hours. The recommended amount of sleep is 7-9 hours and studies show that falling below that can have deleterious effects even after just one night. A 1996 study found that one night of 1-2 hours of sleep reduction will result in an increased heart rate and significantly increase systolic blood pressure the next day. A 2011 study found that progressively shorter sleep was associated with a 45% increase in death from coronary heart disease in the next 7-25 years, and another study found that 5 hours of sleep increases the rate of cold infection by five times. I’m not trying to scare anyone with these studies, I’m only trying to show the importance of sleep and how it can relate to overall health. While sleep scientists don’t know exactly why humans need 7-9 hours of sleep, it is well documented that once we fall below that range for just one night we start to see these types of effects. While it may seem like a good idea to sleep less to work more with the old adage “I’ll sleep when I’m dead” running through your head, studies have even found that people who sleep more make more money. The next section will discuss some of the reasons why that may be in addition to discussing injury and performance related to sleep.
The research is clear, decreased sleep leads to less mental and physical performance in youth and adults. When analyzing motor skill acquisition, one study found that motor skill acquisition (such as typing or learning an instrument) was directly related to the amount of stage 2 non-REM (Rapid Eye Movement) sleep, especially in the last two hours of sleep. A full 8 hours resulted in a 20% speed increase and 35% accuracy increase in typing. Another study found that insufficient sleep resulted in poor supervisor performance which not only decreased the supervisor’s productivity but also the employees directly beneath the supervisor. A Japanese study on identical twins found that sleep is directly correlated with higher intelligence and a high school in Edina, Minnesota after moving back their start time by one hour saw an average 212 point increase in SAT results. The physical ramifications of sleep deprivation aren’t much better. Less than 8 hours of sleep resulted in decreased time to physical exhaustion, decreased vertical jump height, decreased peak and sustained muscle strength, decreased ability to cool down the body, and decreased blood oxygenation. Growth hormone, critical for recovery and muscle building, surges at night but is shut off by sleep deprivation. If coaches, employers, and schools want to improve performance, sleep seems like the best and easiest place to start. The next section will detail how we can improve our sleep which are taken directly from Why We Sleep by Matthew Walker.
Stick to a sleep schedule
Don’t exercise too late in the day
Avoid caffeine and nicotine
Avoid alcohol before bed
Avoid large meals and beverages before bed
Avoid medicines that disrupt sleep when possible
Don’t nap after 3pm
Make sure to leave time to relax before bed
Take a hot bath before bed
Have a dark, cool, gadget free bedroom
Get some sun during the day to regulate sleeping patterns
Get up out of bed if you can’t fall asleep after 20 minutes until you feel sleepy
My hope is that this blog details the importance of enough sleep each night. Once a pattern of proper sleep is required, most patients experience less pain, improved job performance, increased energy, and even an improved mood. This allows you to see us chiropractors less and experience life pain-free more! I also recommend reading Why We Sleep by Matthew Walker for more information as it is a fascinating read and is available at your local library!
Dr. Ryan Hamilton