There are a few myths at the core of the overlap between incretin-based therapies, obesity, muscle mass, and diabetes treatment. A group of experts will examine the impact of these misconceptions and summarize new insights during the symposium, Muscle and Energy Expenditure—Myths, Legends, and Facts, on Monday, June 23, from 8:00–9:30 a.m., in Room W196 BC of the McCormick Place Convention Center.

One of the biggest myths that has shaped diabetes therapy concerns the role of energy expenditure and individual metabolism, said Lara Dugas, PhD, MPH, the AXA Chair in Non-Communicable Disease Epidemiology at the School of Public Health at the University of Cape Town, South Africa, and Professor in the Department of Public Health Sciences at Loyola University Chicago. She will discuss the role of lean body mass in total energy expenditure across the lifespan.

Up to the early 2000s, the consensus was that people living with obesity had metabolic rates that were lower than people living without obesity, and that this predisposed them to weight gain. But research changed that understanding.

“What we were finding is that most people living with obesity and type 2 diabetes actually have metabolic rates in line with their muscle mass,” Dr. Dugas said. “Because our muscle mass is the primary driver of our metabolic rates, we observe, in our studies, that it doesn’t matter if you are a hugely active person or the most sedentary person, your metabolism is tied to your muscle mass.”

She will share studies providing insights into the impact of muscle mass on metabolism and what this means for prevention and management of type 2 diabetes, along with a renewed focus on the impact of processed foods, sugar-sweetened beverages, and other obesogenic environmental factors.

While the diabetes field continues to research the effect of muscles on diabetes, studies are also focusing on the effect diabetes has on muscle mass and muscle strength. Endocrinologist Jose M. Garcia, MD, PhD, Professor of Medicine and Neuroscience at the University of Washington and Director of the Clinical Research Unit and Acting Director of the Geriatric Research Education and Clinical Center at the Puget Sound VA Health Care System, will discuss the relationship between muscle and function.

Muscle mass and strength can be a bulwark for recoveries after heart attacks, strokes, cancer, broken bones, and more, he said, and described muscle mass and strength as “money in the bank” for any individual as they age.

“If you have good muscle mass and function, it will help you recover,” Dr. Garcia said. “Having this good physical function will enable people to be independent for longer, to do the things they want to be doing in the future.”

Dr. Garcia noted that people with diabetes have an increased risk for sarcopenia, the loss of muscle strength and mass, and for dynapenia, the loss of muscle strength even with normal muscle mass. Although both these muscle losses are generally associated with aging, they have also been shown in individuals in their 30s and 40s with type 1 diabetes.

Glycemic management is one of the factors affecting both muscle losses, Dr. Garcia noted, adding that he plans to share research about other factors, such as insulin resistance and inflammation, that might contribute to muscle loss.

It is important for clinicians to be able to understand and communicate this information, Dr. Garcia said, particularly in the context of many new therapies that have been shown to lead to weight loss but whose effects on muscle—and particularly on muscle function—remain unknown.

Weight loss has unquestionable benefits, Dr. Garcia noted. But to preserve muscle health, weight loss objectives should be part of health therapy that includes good diet, protein intake, physical activity, and some combination of endurance and resistance training.

Bret H. Goodpaster, PhD, Scientific Director, Translational Research Institute, will present data on the effect of weight loss on muscle and energy expenditure.

On-demand access to recorded presentations will be available to registered participants following the conclusion of the 85^th Scientific Sessions, from June 25–August 25.