Cardio or Weight Training for Fat Loss: What Works on a GLP-1 Journey?

Cardio (aerobic exercise — walking, cycling, swimming, running) burns calories during the session and supports heart and metabolic health. Weight training (resistance exercise — lifting, bodyweight work, bands) burns fewer calories in the session itself but builds and preserves lean muscle mass, which contributes to a higher resting metabolic rate over time.

Why muscle preservation matters on GLP-1 medicines

When appetite is significantly reduced — a commonly reported effect for people on Mounjaro or Wegovy — the body can lose muscle alongside fat if protein intake and resistance training are not prioritised. Many exercise physiologists suggest that for people in a calorie deficit, resistance training is particularly valuable because it signals the body to hold onto muscle. This does not mean cardio is unhelpful; it means the two work well together rather than in competition.

What the general guidance suggests

• Resistance training 2–3 times per week is commonly recommended for people aiming to preserve lean mass during weight loss.
• Cardio 2–5 times per week — even brisk walking — adds to energy expenditure and supports cardiovascular health.
• Protein intake works hand-in-hand with resistance training; hitting a daily protein target helps muscle repair and retention. This is covered in more depth in our guide to weight training for fat loss on GLP-1.

The honest answer to "which is better" is that they serve different purposes and complement each other. For someone short on time, adding two resistance sessions per week alongside daily walking is a practical starting point that many people find manageable — but the right plan is always one you can stick to and one your healthcare professional supports.

If you are curious about running both simultaneously, see our page on combining cardio and weights for fat loss, and for a deeper look at whether resistance work alone moves the needle, whether weight training is good for fat loss explores the evidence in more detail.

Knowing what you are doing in theory is one thing; seeing how it actually affects your results is another. GLP Trackr's insights and analytics are built to surface exactly this kind of pattern from your own data — for example, whether the weeks you hit your step or activity targets correlate with stronger progress on the scale or in your measurements.

The weight and body tracking features let you log not just your weight but also measurements over time, so you can see body composition shifts that the scale alone might miss — relevant when resistance training can increase muscle density while fat is reducing. Progress sometimes looks stalled on the scale but is clearly visible in measurements and how you feel.

You can also set a daily steps target and track it alongside your food and protein, giving you a joined-up picture of the inputs that drive your results. Bringing that data to a prescriber appointment, via the doctor report feature, means your conversations are grounded in your actual journey rather than rough recollections.

For broader context on your Mounjaro journey — including how lifestyle factors fit in — visit our Mounjaro overview hub.

Any decisions about your exercise programme, particularly if you have existing health conditions, are worth discussing with your prescriber or doctor — they know your full picture and can advise on what is appropriate for you.

Ready to see how your activity, weight and progress connect? Download GLP Trackr on the App Store or Google Play and start a free 7-day trial — no commitment needed.