Resistance exercise to attenuate lean mass loss during tirzepatide therapy for obesity: a randomized controlled trial
Green DJ, Haynes A, Underwood DR, et al. (2026). Nature Medicine.
Summary
A single-centre, investigator-led randomised trial (T-REx, ACTRN12623001236684) in 120 adults aged 50 to 70 with overweight or obesity. Everyone received tirzepatide for 40 weeks and was randomised to three supervised resistance-training sessions a week or to usual activity. Weight loss was similar: 22.28 kg with training and 22.61 kg without. Loss of lean soft tissue was 1.09 kg smaller with training (3.57 kg versus 4.67 kg; 95% confidence interval for the difference 0.43 to 1.75 kg). Strength fell by 6.5% to 9.0% on tirzepatide alone and rose by 10.7% to 17.5% with training, across bench press, lat pulldown and knee extension. Eli Lilly supplied tirzepatide and had no other involvement in the trial. Published online on 9 November 2026.
Peptides in this study
Tirzepatide in the United Kingdom · Tirzepatide in the United States · Tirzepatide in Australia