1. Enhanced Muscle Recovery:
During deep sleep stages, the body releases growth hormone, which is essential for muscle repair and growth. Without adequate sleep, not only is the secretion of this hormone reduced, but the body’s ability to repair muscle tissue post-exercise is also impaired. This can lead to prolonged recovery times and decreased performance, ultimately stalling progress in strength and fitness levels.
2. Improved Energy, Strength and Performance:
Studies show that adequate sleep can improve physical performance, including strength, speed, and accuracy, making workouts more effective and productive.
3. Optimized Fat Loss:
Sleep affects the levels of hormones that regulate appetite, namely ghrelin and leptin. Proper sleep helps maintain a balance of these hormones, reducing cravings and helping you manage your diet more effectively for fat loss. Lack of sleep is strongly linked to weight gain and obesity.
A review and meta-analysis found that short sleep duration increased the likelihood of obesity by 89% in children and 55% in adults. The mechanisms involve alterations in hormones that regulate appetite—ghrelin and leptin—along with increased appetite and caloric intake, particularly of high-carbohydrate snacks.
Additionally, insulin, which helps regulate glucose processing and promotes fat storage, is directly affected by sleep. Insufficient sleep can lead to higher blood sugar levels and reduced insulin sensitivity, increasing the risk of fat accumulation and type 2 diabetes.
Sleep has also been found to influence the rate at which your body burns calories at rest (resting metabolic rate). Better sleep helps maintain a higher metabolic rate, aiding in weight management.
4. Metabolic Health and Diabetes
Sleep deprivation is closely linked to adverse effects on glucose metabolism and type 2 diabetes risk. A meta-analysis published in Diabetologia concluded that people who habitually sleep less than 5 hours per night have a 57% increased risk of developing type 2 diabetes. Furthermore, experimental studies, like those published by the Annals of Internal Medicine, have shown that cutting sleep to four hours per night for multiple nights in a row impairs glucose metabolism and increases insulin resistance, which are precursors to diabetes.
5. Cognitive Decline and Impaired Brain Function:
Sleep is crucial for cognitive processing. Persistent sleep deprivation can impair cognitive functions, including memory, attention, and decision-making. Research from Nature Communications suggests that sleep deprivation can have a significant negative effect on brain function, equivalent to up to seven years of aging in middle-aged adults. This can manifest as reduced cognitive speed and accuracy, impacting both professional and personal life.
6. Compromised Immune Function
Even moderate sleep deprivation has been shown to impair immune function. A study published in JAMA Internal Medicine found that people who slept less than 7 hours per night were nearly three times more likely to develop a cold compared to those who slept 8 hours or more. This is due to decreased production of cytokines and other critical immune responses during sleep deprivation. Sick days are missed workout days, and no one wants that.
7. Reduced Injury Risk
A study published in the Journal of Pediatric Orthopaedics found that adolescent athletes who slept fewer than 8 hours per night were 1.7 times more likely to experience an injury compared to those who slept for 8 hours or more. This relationship between sleep duration and injury risk is thought to be due to several factors associated with sleep deprivation, including decreased reaction times, impaired cognitive function, and a compromised healing process.
Additionally, fatigue attributable to lack of sleep can impair judgment and increase the likelihood of taking unnecessary risks during physical activity. These findings underscore the importance of adequate sleep for injury prevention in active populations.
8. Reduced Risk of Cardiovascular Disease
Research consistently shows that individuals who sleep less than 7-8 hours per night have a greater risk of developing heart disease and stroke. According to a study published in the European Heart Journal, short sleepers (under 6 hours per night) have a 48% increased risk of developing or dying from coronary heart disease and a 15% greater risk of developing or dying from stroke. The relationship between sleep and heart health is attributed to the effects of sleep on blood pressure, cholesterol, and inflammation.
These data points highlight just how critical sleep is across various systems in the body, underscoring it not just as a pillar of health on par with diet and exercise, but as a foundational element that supports every aspect of our well-being.
Prioritizing your sleep is as essential as your diet and workout regimen when it comes to achieving and maintaining peak physical fitness. Ensuring at least 7 hours of quality sleep each night sets a solid foundation for reaching your fitness goals and leading a healthier life.
But Yvette, I’ve tried!
I know… if you’re struggling with sleep, turning it around is not as simple as ‘go to bed earlier’!
I also know that with intention and a plan, you can turn things around and improve your sleep. It does take time and consistency, like everything worth having – but it is possible. I’ve seen it again and again. Check out our guide to improving your sleep here.
You might also consider one of our challenges RxHABITS or GRIT50, where we include sleep as one of the fundamental best practices we work on together 😴
