Desire to burn fat without sacrificing muscle mass? Examine This Easy Diet Adjustment
More fat is lost when intermittent fasting and exercise are combined than when either is done alone.
Although time-restricted eating has gained popularity among weight-loss enthusiasts, its efficacy is still debatable.
Nonetheless, there is encouraging evidence from a recent University of Mississippi study that was published in the International Journal of Obesity (Nature Publishing Group). Researchers discovered that healthy adults who exercised regularly and adhered to an eight-hour eating window lost more body fat without losing lean muscle than those who exercised alone.
"When healthy adults followed both exercise and time-restricted eating for at least 4 weeks, we saw that this did lead to more fat loss and reduced body fat percentage over time," said assistant professor of nutrition and hospitality management Nadeeja Wijayatunga.
"Noting the preservation of lean mass is important."
The study was started in response to the increasing popularity of time-restricted eating by Wijayatunga and Michael Hays, a tactical dietitian and recent University of Mississippi graduate. In their systematic review and meta-analysis, they looked at information from 15 studies published in the last ten years that investigated the effects of combining exercise and time-restricted eating.
Intermittent fasting, a broad category of diets that alternate between periods of eating and fasting, includes time-restricted eating.
"Time-restricted eating is popular because people find it easier to follow because they do not have to think about it too much," she said. "Time is everything; it is not about tracking calories or avoiding particular foods."
Reasons Why Many Find Time-Restricted Eating Appealing
According to the 2023 International Food and Health Survey, 12% of Americans have tried intermittent fasting, making it one of the most well-liked diets in the country.
But according to Hays, the science behind time-restricted eating is still evolving.
According to Hays, "this may be a good technique for some people to help with body composition goals." "It is just another tool, but more research is necessary to fully comprehend how this functions in humans."
The two groups in the studies were already very healthy people, according to Hays, even though there was a small difference between those who exercised while on a time-restricted diet and those who just used exercise.
These were generally healthy adults, according to Hays. They were already exercising regularly and were in good physical shape. It is important to reduce the body fat percentage of athletic, slender individuals who already exist.
Resolving Issues With Lean Mass Loss
Time-restricted eating has drawn criticism for potentially causing a loss of lean mass, which includes all of the body's muscles, organs, and other tissues.
"Healthy muscles are essential," Wijayatunga stated. Your body and metabolism depend heavily on your muscles. Losing muscle simply reduces our overall mobility and may have an effect on our metabolic systems.
In their study, Hays and Wijayatunga discovered that even for those who lost body fat, time-restricted eating did not result in a decrease in lean mass when combined with exercise.
"That is why you want to combine exercise and diet," Hays stated. Lean tissue loss is the last thing you want to happen when trying to lose weight. You wish to reduce your body fat.
Wijayatunga cautioned that although the results are encouraging, more research is required to validate them. Although the participants in this study were healthy and active, it is important to consider the implications for those who are not in good physical shape and do not regularly exercise.
"That is something that requires further research," she stated. "With advice from a health care professional, I would advise establishing healthy habits that you, as an individual, can sustain."
Reference: "Effects of time-restricted eating with exercise on body composition in adults: a systematic review and meta-analysis," International Journal of Obesity, 10 January 2025, by Harry M. Hays, Pouria Sefidmooye Azar, Minsoo Kang, Grant M. Tinsley, and Nadeeja N. Wijayatunga.