Exercise Key to Regaining Fitness After GLP-1-Assisted Weight Reduction: Study Suggests - Video

A new study published in Sports Medicine shows that exercise, not weight-loss drugs alone, is the key to improving physical fitness after weight loss in people with obesity.

Obesity affects over 650 million adults worldwide and is often linked to poor mobility, low stamina, and difficulty performing everyday tasks like climbing stairs. While weight-loss diets and medications such as GLP-1 receptor agonists (including liraglutide) can help people lose weight, researchers wanted to know whether weight loss by itself actually improves physical fitness.

In this study, adults with obesity first followed a very low-calorie diet and lost at least 5% of their body weight. They were then followed for one year and divided into four groups: no treatment, exercise only, liraglutide only, or a combination of exercise and liraglutide.

The results were clear. Participants who exercised—either alone or with liraglutide—showed the biggest improvements in fitness and mobility. They climbed stairs faster, had better heart and lung fitness, and maintained muscle strength. In contrast, those who took liraglutide without exercise did not see meaningful improvements in physical performance, even though they maintained weight loss.

Importantly, the study found that more exercise led to better results. Even small increases in weekly physical activity improved stamina and mobility.

Muscle strength was preserved across all groups, but muscle quality declined in participants who neither exercised nor took medication.

Overall, the findings highlight that exercise plays a central role in long-term health after weight loss. While GLP-1 drugs help with weight control, combining them with structured exercise delivers the greatest benefits for physical fitness, independence, and quality of life.

REFERENCE: Jensen, S.B.K., Fiorenza, M., Juhl, C.R. et al. Physical Fitness with Exercise and GLP-1 Receptor Agonist Treatment Alone or Combined After Diet-Induced Weight Loss: A Secondary Analysis of a Randomized Controlled Trial in Adults with Obesity. Sports Med (2026). DOI: 10.1007/s40279-025-02386-0, https://link.springer.com/article/10.1007/s40279-025-02386-0