Did you know there’s more to a healthy lifestyle than eating right and moving your body? Of course! However, did you know that adding in more of this particular action can help improve brain function, regulate satiety hormones, and help build and repair muscle tissue? If it’s not obvious by now what this action is, it’s getting more restful sleep. Getting more restful sleep improves many functions of daily life. Let’s explore how getting more restful sleep can help with fat loss and muscle maintenance.
Improved Body Composition and Hormone Levels
A crossover study involving overweight adults assigned participants to sleep for either 8.5 hours or 5.5 hours while following a moderate caloric deficit (~680 calorie deficit) for 2 weeks in a lab setting. The group who slept for only 5.5 hours lost 55% less body fat and 60% more fat-free mass than the 8.5 hour group. The 5.5 hour group also showed less-favorable changes in metabolic hormone levels and substrate use. The 8.5 hour group lost twice as much energy (1039 kcal/day) compared to the 5.5 hour group (573 kcal/day). The participants that did not get enough sleep preserved more energy-dense fat mass and less lean tissue while in the caloric deficit.
Another interesting finding from this study was that participants from the 5.5 hour group experienced higher ghrelin levels (the hunger perception hormone). Accompanying the increased ghrelin levels may have been the retention of fat and increased hunger making it harder to adhere to the dietary intervention leading to less weight loss.
Maintaining and building muscle are processes that happen outside of the gym environment. Proper muscle recovery can only happen through proper rest and nutrition. A process that is heavily affected by sleep quantity and quality is muscle protein turnover. Muscle protein turnover is the balance between muscle protein synthesis and breakdown. According to Human Kinetics Journals, MPS is “the metabolic process that describes the incorporation of amino acids into bound skeletal muscle proteins.” Muscle protein synthesis is what is mostly responsible for increases in muscle mass in response to resistance training. According to this article on sleep and muscle recovery, “sleep debt decreases the activity of protein synthesis pathways and increases the activity of degradation pathways, favoring the loss of muscle mass and hindering recovery [post] exercise.” This study is congruent with the study listed above that showed the 5.5 hour sleep group losing more lean mass and less fat mass than the 8.5 hour sleep group. It is very apparent that getting less sleep is detrimental to muscle recovery and fat loss, two important processes for both aesthetic and health considerations.
Clearly, sleep is not for the weak, as some “boss babes” or “hustle hunks” may claim. Understand that part of being a holistically healthy human being is getting proper rest, recovery, and nutrition, not just working hard non-stop. There are no losses when proper sleep is implemented into your routine, especially if it can help improve quality of life and longevity. Aim to get at least 7-9 hours of sleep per night and keep track of how restful it is each time. Doing so will only help you regulate your hormone levels, stick to your nutrition plan, build muscle, and also not be a cranky human being. You might not need as much coffee if you sleep a little more too. 🙂 Get to rest!
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