Why strength training really matters when using GLP-1 treatment
GLP-1 medications can be highly effective for weight loss, but weight loss is never just about fat. Whenever body weight decreases, some muscle is lost too, and with GLP-1s, this loss can be greater than with diet and exercise alone if muscle health isn’t actively protected.
That’s why strength training and good nutrition, particularly adequate protein, are essential parts of any GLP-1 weight-loss plan, not optional extras.
How much activity is recommended?
NHS guidance recommends that adults aim for:
- At least 150 minutes a week of moderate-intensity physical activity
- Strength-building exercise on two or more days each week
Moderate-intensity activity means your heart rate increases, and you feel warmer and comfortably breathless, but you can still talk in short sentences. Examples include brisk walking, cycling on level ground, swimming, or water aerobics.
Why muscle matters – especially during weight loss
Muscle plays a key role in strength, balance, mobility, independence, and metabolic health. Healthy muscle helps the body use glucose more effectively, supports insulin sensitivity, and contributes to better blood sugar and energy regulation.
As we age or become less active, muscle quality naturally declines and fat can infiltrate muscle tissue, making it weaker, a process known as sarcopenia. People who are older, less active, or already at risk of muscle loss are therefore more vulnerable to losing strength during weight loss, particularly if weight loss happens quickly.
How much protein do you need?
During weight loss – and especially when using GLP-1 medication – most experts recommend aiming for around:
1.2–1.6 grams of protein per kilogram of body weight per day
This higher protein intake helps preserve muscle mass, support strength, and improve satiety, particularly when overall calorie intake is reduced. Protein should ideally be spread evenly across meals rather than concentrated in just one.
Practical protein examples include:
Vegetarian and vegan sources
- Lentils, chickpeas, beans (including soybeans and edamame)
- Tofu, tempeh, soya mince
- Quinoa, oats, whole grains (best combined with legumes)
- Nuts, seeds, nut butters
- Plant-based protein yoghurts or fortified alternatives
Animal-based sources
- Eggs
- Greek-style yoghurt, cottage cheese
- Chicken or turkey breast
- Lean cuts of meat
- Fish or seafood (if included in the diet)
Mixing protein sources helps ensure you get all the essential amino acids your muscles need.
The role of strength training
Strength training sends a powerful signal to your body to hold on to muscle during weight loss. Effective options include resistance bands, light weights, body-weight exercises, or gym-based machines. The best programme is one that is safe, enjoyable, and sustainable.
Taking a personalised, monitored approach
For people already at risk of sarcopenia, a slow, steady approach to weight loss with regular review is especially important. GLP-1 treatment plans can be adjusted over time, including exercise focus, protein intake, weight targets, or medication dose, to ensure weight loss supports long-term strength, function, and quality of life.
Our weight loss expert’s key message
“GLP-1 medications can be a powerful tool for weight loss, but muscle health needs attention from the very start,” comments our specialist GP in Obesity and Weight Management, Dr Ulrike Naumann. “Regular movement, strength training, adequate protein, and good overall nutrition help ensure weight loss supports metabolic health, mobility, and long-term independence, rather than leading to frailty.
“Health is more than a number on the scale – your muscles matter.”
For more advice from Dr Naumann, get in touch to arrange an appointment at our Weight Loss Clinic. Explore how medical expertise, lifestyle guidance, and – where appropriate – judicious use of medication can support your goals.
