Ozempic, Wegovy, Mounjaro & Zepbound Muscle Mass Worries

Semaglutide, sold as Ozempic and Wegovy, and tirzepatide, sold as Zepbound and Mounjaro, are new therapies for weight loss that actually work, helping millions around the world to feel better. But some people are fearful of side effects, such as loss of muscle mass. Are their fears warranted? To find out, Marty and Stu talk to the two University of Kansas weight loss scientists, Renee Rogers and ACSM president-elect John Jakicic, who are leading a clinical trial investigating the way aerobic and resistance training can affect the muscle mass of people who are on GLP-1s. In this episode we discuss: —the latest findings on how GLP-1s affect muscle mass —the research that Jakicic and Rogers are doing into GLP-1s, weight loss and muscle mass —we provide guidance on whether people should be concerned about GLP-1s and muscle mass —we also provide pointers on how to minimize muscle loss while on GLP-1s Plus, Renee and John discuss whether the new weight loss therapies affect men and women differently. Have a listener question? Email us at [email protected] Exercise Science is powered by ‪@myeverme‬, the longevity intelligence app. Download EverMe for free at your favourite app store. Exercise Science listeners get a free two-month trial to EverMe at this link: https://www.everme.ai/exercisescience Exercise Science sponsor Precision Nutrition is the #1 most recommended nutrition certification program in the world. And now it specializes in GLP-1 coaching. For a free assessment to learn your GLP-1 type, visit: http://GLPCoaching.com LINKS Exercise Science is everywhere @realexercisescience: Substack: http://realexercisescience.com Instagram:   / realexercisescience   Apple Podcasts: https://podcasts.apple.com/us/podcast... Spotify: https://open.spotify.com/show/29lBGiR... X: https://x.com/realexscience Stu is everywhere, too, @mackinprof, but mostly on Instagram:   / mackinprof   Stu on X: https://x.com/mackinprof Marty just started his own Instagram. Give him a follow!   / gibalajm   He’s also on X! https://x.com/gibalam Exercise Science is produced by Ghost Bureau, the Toronto content agency. https://ghostbureau.com/ EPISODE LINKS New York Times: They Hated Exercise. Weight Loss Drugs Changed Everything https://www.nytimes.com/2026/02/23/we... Renee Rogers and John Jakicic’s clinical trial: Muscle and Movement With Anti-Obesity Medications (M3) https://clinicaltrials.gov/study/NCT0... A paper by John Jakicic and Renee Rogers advocating for a prescription of exercise along with obesity medication in obesity treatment: The Role of Exercise in the Contemporary Era of Obesity Management Medications https://journals.lww.com/acsm-csmr/ab... Jakicic led, and Rogers coauthored, the largest targeted NIH investment of funds into the mechanisms of how physical activity improves health and prevents disease. Study website: https://www.motrpac.org/ Analysis: Preserving muscle mass on GLP-1 weight loss drugs: Big Deal or Nothing to Worry About? By Stuart Phillips https://theconversation.com/preservin... DISCUSSION POINTS 00:00 Cold open 01:29 Muscle mass and GLP-1s 04:19 Introducing Renee and John 06:19 GLP-1 context 07:50 How GLP-1s work 10:50 More than GLP-1s 12:44 Body composition & weight loss 15:00 Lean tissue is not muscle 16:50 Overblown fears 18:55 Muscle moment 20:39 R01 study described 23:15 Early results 26:04 Behavioural influences 28:45 Rediscovering exercise 31:09 Comprehensive care 33:00 Renting weight loss 36:55 Obesity drivers 37:47 Older adults 40:39 Wraparound care 41:30 Muscle health context 43:12 Function measures matter 44:44 Lean v. muscle 46:15 Unloading the body 47:40 GLP-1 sex differences 49:44 How to minimize muscle loss on GLP-1s 53:33 Wrap up DISCLAIMER The Exercise Science podcast is for educational and entertainment purposes only and is not a substitute for professional medical advice. Strength training and fitness carry inherent risks. Always consult with a physician or qualified healthcare provider before starting any new exercise program or making changes to your diet. The hosts, producers, sponsors and guests of this podcast disclaim any liability for any injuries or losses connected with the information discussed in this show. The science of strength and fitness is continually evolving. While we strive to provide accurate, evidence-based information, we make no representations or warranties regarding the completeness, accuracy, or timeliness of the information discussed. Martin Gibala is an advisor to and holds equity in Longevity League Ltd., a US-based company whose services in part relate to exercise.