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When it comes to joining CrossFit, we all have specific goals in mind, such as building strength, endurance, and achieving an impressive body composition with weight loss. We dedicate ourselves to disciplined diets and intense workouts, investing time and effort to achieve these goals. However, despite our consistency, we often fall short of the direct results we desire. This raises the question: what could be the missing link? Perhaps, it’s your sleep.
Recent research has shed light on the significant impact of sleep on our efforts to reduce overall body fat. The study involved a group of individuals who spent two weeks at the University of Chicago Sleep Research Laboratory. These participants were provided with identical dietary plans to create a substantial energy deficit, and they experienced two different sleep conditions: one with full sleep availability of 7.5 hours and the other with restricted sleep of only 5.5 hours.
Interestingly, both groups seemingly lost a similar amount of weight, approximately 6.6 pounds or 3 kilograms. However, a closer examination of the data reveals a stark difference in how each group lost weight. The group with restricted sleep experienced a significant decrease in how their bodies used and distributed nutrients. Specifically, they lost 5.3 pounds (2.4 kg) of fat-free mass and only 1.3 pounds (0.6 kg) of fat mass. In comparison, the group with sufficient sleep lost 3.3 pounds (1.5 kg) of fat-free mass and an impressive 3.1 pounds (1.4 kg) of fat mass, as confirmed by DXA scans.
sleeping 5 hours instead of 7.5 hours reduces fat loss and increases muscle loss by over 50%
Renowned fitness researcher Menno Henselmans commented that it is clear “that sleeping 5 hours instead of 7.5 hours reduces fat loss and increases muscle loss by over 50%. These findings underscore the fact that sleep quality is often underestimated within the fitness community.”
This study highlights the critical role of prioritizing sleep as an essential component of our fitness routines. By allowing ourselves the necessary time to rest and recover, we can enhance how our bodies utilize and distribute nutrients, preserve muscle mass, and promote effective fat loss.
If you consistently put in effort without seeing the desired results, it’s crucial to examine your sleep habits closely. Make sleep a priority in your fitness journey, just as you prioritize diet and exercise. By recognizing the power of quality sleep and its impact on body composition, you can unlock the missing link that may have been hindering your progress. Reach out to the CrossFit Anaheim team today to access the resources you need to improve your sleep and achieve the rest you deserve.
Nedeltcheva AV, Kilkus JM, Imperial J, Schoeller DA, Penev PD. Insufficient sleep undermines dietary efforts to reduce adiposity. Ann Intern Med. 2010 Oct 5;153(7):435-41. doi: 10.7326/0003-4819-153-7-201010050-00006. PMID: 20921542; PMCID: PMC2951287.
