Importance of Sleep for an Active Lifestyle
McKenzie Redd, DPT, Certified Pelvic Health Specialist, CPR Employee
When it comes to achieving optimal health and wellness, or recovering from an injury, we often focus on exercise and nutrition. However, one vital aspect that often gets overlooked is sleep. Sleep is essential to our overall well-being, and its impact on physical performance should not be underestimated. Whether its avoiding injury, recovering from an injury, or just trying to optimize health, sleep is vital.
Getting enough sleep is not just a luxury, it should be a priority. Yet the CDC estimates that around one-third of adults in the United States get less than 7 hours of sleep a night and nearly half of the adult population has trouble sleeping at night. Sleep deprivation over time has been linked to many different health risks including weight gain, heart disease, increased risk of type 2 diabetes, and reduced immune function. While each person is unique in how much sleep they need, for adults it is recommended to get at least 7-9 hours regularly.
Sleep is a necessary part of our biologic processes. During our sleep cycle, our body goes through different phases that help with different cognitive and physical repair functions. The two main phases of sleep are:
Non-REM sleep: Occurs first in the sleep cycle and is when deep sleep occurs. Typically, it is very hard to wake from this stage. During this stage of sleep the body builds bone and muscles, releases important hormones and chemicals to help repair the body from any injury or tissue strain.
REM Sleep: Happens later in the sleep cycle and includes dreaming states. During REM sleep, brain activity looks similarly to when we are awake. REM sleep helps with brain development, emotional processing, and memory consolidation. It is usually much easier to be awoken in these stages of sleep.
These two cycles will repeat throughout the duration of sleep and a full sleep cycle takes about an hour and a half. Age will dictate how long each cycle will be, with typically younger children, teens and young adults requiring more REM and non-REM sleep rather than just light sleep.
In regards to physical function and health, deep sleep during non-REM cycle is the most important. During deep sleep stages, the body releases growth hormone, which promotes tissue regeneration and the healing of micro-tears that occur during day to day life. Majority of physical recovery happens in non-REM sleep cycles. Without sufficient sleep, these repair processes are compromised, leading to reduced muscle growth, increased risk of injuries, and longer recovery times.
In fact, studies have shown that athletes that get less than 7 hours of sleep have a 1.7x greater risk of injury than teenage athletes getting more than 8 hours of sleep. Even more so, if athletes are getting less than 6 hours of sleep, the rate of injury increases to 4x greater than players getting more than 9 hours of sleep.
Regular and quality sleep is crucial for injury prevention. Sleep deprivation weakens the immune system, making the body more susceptible to illness and infections. This weakened immune response hinders the body's ability to recover from injuries and increases the risk of overuse injuries, stress fractures, and other musculoskeletal problems. One study that assessed sleep quality and functional disability in patients with chronic low back pain showed a significant association between poor sleep quality and increased disability, suggesting that addressing sleep disturbances may have a positive impact on reducing disability in individuals with low back pain.
Sleep and Pain Sensitivity
Sleep can also be a powerful painkiller. Multiple studies have found that even after brief bouts of sleep deprivation, that pain sensitivity can increase. In studies that compare people who have chronically been deprived of sleep, such as in insomnia, versus those that are getting regular bouts of sleep, researchers found that those with sleep deprivation reported pain symptoms on twice as main days as those without deprivation in a 2 week period.
Cognitive Function and Coordination
Sleep has a profound impact on cognitive function and coordination, which are critical for optimal physical performance. Sleep deprivation negatively affects attention, concentration, reaction time, decision-making abilities, and overall coordination. These cognitive impairments can be detrimental to sports performance, leading to decreased accuracy, slower reflexes, and an increased risk of injuries.
The benefits of sleep just continue to grow as a researchers learn more about sleep processes. To live a healthy lifestyle, and stay physically active, sleep should be a priority. However, for some people, sleep quality can be challenging to achieve, whether they struggle with falling asleep or staying asleep. In which case, establishing a good sleep routine can be beneficial in the goal of sleeping with better quality, even if duration is limited.
Strategies for Optimizing Sleep
- Consistency: Try falling asleep and waking at the same time everyday, even on weekends. This helps to establish a circadian rhythm and allows our body to anticipate sleep/wake cycles.
- Cold: Dial your thermostat between 60-65 ̊. Ideally, the cooler the room, the easier it is to fall into deep sleep phase.
- Dark: The darker the better. To avoid disrupting our melatonin production during sleep cycles, the sleeping environment must be as dark as possible. Use blackout curtains, or a sleep mask to achieve a dark enivironment.
- Light: Seeing bright light in the morning will help with falling asleep easier at night and feeling more alert during the day. There are certain cells in the eye that are sensitive to light, and when exposed to natural light, help regulate the circadian rhythm to be more synchronized with sunrise and sunset.
- Avoid electronics at night. Those same cells that are sensitive to natural light and help regulate the awake and sleep cycles can be affected by electronics. When we are exposed to light early in the morning, it pushes our sleep cycle earlier. When light exposure happens later at night, it can push the sleep schedule later and affect the quality of sleep we achieve. Artificial light before bed can give conflicting messages to the brain, delaying sensation of tiredness and ability to fall asleep.
- Avoid caffeine after noon. Caffeine consumption has been shown to result in people falling asleep later, getting less hours of sleep overall, and limiting the amount of deep, slow wave sleep, which is a critical stage of sleep for feeling refreshed the next day. The rule of thumb is to avoid consuming any caffeine within 7 hours of sleep in order to allow the effects to wear off before sleep.
- Prioritize Physical Activity. Exercise can help with sleep quality and improve ability to fall asleep quicker. Physical activity and exercise should be avoided 1-2 hours before bed as that can interfere with the winding down process to fall asleep.
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