GLP-1s have taken the world by storm. Highly effective and paired with diabolical marketing strategies, they are becoming as common as Tylenol and Chapstick.
We’ve all heard the commercials. We know that GLP-1s help lower blood sugar, slow stomach motility, and make you feel fuller longer.
But what else are they doing in your body?
Although there is no conclusive data that shows the use of weight loss medications causes bone-density loss, rapid weight loss DOES cause bone density loss.
And what happens when you start taking a GLP-1? Rapid weight loss.
One sure-fire way to prevent significant bone density loss is through consistent exercise. The Journal of Sport and Health Science published a study looking at this topic. Two groups of obese people were studied; one group was given a diet-induced weight loss program while the other group was given a diet and exercise combination program. Bone density was measured at the femoral head before and after weight loss. The group that used diet AND exercise to lose weight had higher femoral head bone density than the diet only group (1).
Another side effect of rapid weight loss is skeletal muscle loss. The muscles that help you stand up and step up are directly altered by changes in calorie consumption. “Long-term clinical data from 2025 and 2026 has made one reality undeniable. Up to 40% of the weight lost on high-efficacy GLP-1 medications is not fat; it is lean body mass.” (2) Loss of lean body mass results in a frail body that cannot move or recover well. Your risk of injury skyrockets and your quality-of-life sneaks away.
Easy solution? Hit the gym. Weight training, functional fitness training, Cross Fit, etc are all fantastic ways to keep your bones and muscles intact as your body changes.
“strong muscles lead to strong bones” (3)
At Bully Fitness, we are well-versed on the effects of GLP-1s on the body. Some of our coaches have utilized them and become very familiar. Our nutrition counseling coaches are also comfortable and experienced in managing the needs of someone using weight loss drugs.
If it is stigma you’re worried about, there is no judgement here.
We all started somewhere, we all stepped into the gym for the first time too
Everyone in our Pack is open, understanding, and encouraging to those who are new to the gym space. Give us the gift of getting to know you!
- Mesinovic, J., Jansons, P., Zengin, A., de Courten, B., Rodriguez, A. J., Daly, R. M., Ebeling, P. R., & Scott, D. (2021). Exercise attenuates bone mineral density loss during diet-induced weight loss in adults with overweight and obesity: A systematic review and meta-analysis. Journal of Sport and Health Science. https://doi.org/10.1016/j.jshs.2021.05.001
- Mills, T. (2026, February 23). The GLP-1 Aftermath: What the Science Says About Muscle Loss and Cellular Aging – Harvard Science Review. Harvard Science Review. https://harvardsciencereview.org/2026/02/23/the-glp-1-aftermath-what-the-science-says-about-muscle-loss-and-cellular-aging/
- Harvard Health Publishing. (2024, January 16). Strength training builds more than muscles – Harvard Health. Harvard Health; Harvard Health. https://www.health.harvard.edu/staying-healthy/strength-training-builds-more-than-muscles