Preservation of lean soft tissue during weight loss induced by GLP-1 and GLP-1/GIP receptor agonists: A case series.
Tinsley. Grant M GM; Nadolsky. Spencer S
Key Findings
- Resistance training 3‑5 days/week and overall activity 4‑7 days/week helped preserve or increase lean mass during tirzepatide treatment
- Protein intake of about 0.7‑1.7 g per kg body weight (or 1.6‑2.3 g per kg fat‑free mass) was linked to lean‑mass gains
- Weight loss ranged from ~13% to 33%, but lean‑soft‑tissue loss was only 6.9% in one case and actually increased (+2.5% to +5.8%) in the other two
Practical Outcomes
- When using tirzepatide for weight loss, pair it with 4‑7 days/week of activity, including 3‑5 days of resistance training, and aim for protein around 1.6‑2.3 g per kg of fat‑free mass daily. This strategy can help you shed fat while preserving or building muscle.
Summary
In three people who used tirzepatide (or semaglutide) for weight loss, those who added regular resistance training and ate enough protein kept or even added muscle while dropping fat. This shows you can lose weight with these drugs without losing lean tissue if you train hard and hit protein targets.
Abstract
GLP-1 receptor agonists (e.g., semaglutide) and dual GLP-1/GIP receptor agonists (e.g., tirzepatide) are effective for reducing body weight and fat mass, though lean soft tissue loss comprised 26%-40% of weight loss in recent trials. This case series describes three patients (two female, one male; body mass index: 32.9-51.9 kg m<sup>-2</sup>) who prioritized lean soft tissue preservation strategies during treatment with semaglutide or tirzepatide. Patients engaged in intentional exercise or structured physical activity 4-7 days·week<sup>-1</sup>, including resistance training 3-5 days·week<sup>-1</sup>. Typical protein intakes were 0.7-1.7 g·kg<sup>-1</sup>·day<sup>-1</sup> relative to body mass and 1.6-2.3 g·kg<sup>-1</sup>·day<sup>-1</sup> relative to fat-free mass. Changes in weight, fat mass, and lean soft tissue were: -33.0%, -53.4%, and -6.9% (case 1); -26.8%, -61.6%, and +2.5% (case 2); and -13.2%, -46.9%, and +5.8% (case 3). Accordingly, one patient lost 8.7% of weight as lean soft tissue, while two increased lean soft tissue. These findings highlight the potential for some individuals to preserve or even increase lean soft tissue during treatment with semaglutide or tirzepatide alongside supportive lifestyle strategies.
Study Information
pubmed
2025
2025-10-16T00:00:00.000Z
10.1177/2050313x251388724