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A bunch of people online are asking whether the new weight-loss drugs tirzepatide (sold as Tirz) and retatrutide (Reta) make women lose their butt muscles (glutes) even when they lift weights. The posts are basically personal reports and questions, not formal studies. People want to know whether the drugs make you lose shape or whether you can keep or even build your glutes by adjusting workouts, protein, or calories. Tirzepatide is a prescription medicine that combines two hormone-like actions to lower appetite and help people lose weight. It mimics gut hormones that tell your brain to eat less and can slow how fast your stomach empties. Retatrutide is a newer experimental drug that works in a similar way but is still being tested; it aims to reduce appetite and body weight, and it’s not widely approved yet. Neither drug is a “muscle-killer” by design — they reduce overall body weight by cutting appetite and sometimes changing where fat is lost — but they also reduce calorie intake, which can affect muscle if you don’t protect it. What’s actually out there is mostly anecdotes and small user threads, plus some clinical trial data that focus on overall weight and fat loss rather than specific body parts like the glutes. Trials show tirzepatide can produce substantial weight loss on average, and a fair part of that is fat, but a little muscle loss often happens with rapid weight loss too. The user reports vary: some women who already lift and prioritize protein say they maintained or even improved their glutes, while others report some flattening or loss of fullness. Those differences likely come down to how they trained, how much protein they ate, and how large the calorie deficit was. Why this matters is simple: many people want to lose fat without losing the muscle they worked hard for, especially in areas like the butt that affect appearance and strength. If you’re already lifting and care about keeping your glutes, the takeaway is that it’s possible to retain muscle while on these drugs, but it usually takes intention. That means continuing resistance training that targets the glutes, keeping protein intake fairly high for your size, avoiding extreme calorie cuts, and giving your body time. Anyone focused on body shape should plan workouts and diet deliberately rather than expecting the drug alone to preserve muscle. Caveats: the online posts aren’t rigorous science. Individual results vary a lot. Clinical trials measure overall muscle and fat changes but don’t always report how one body part looks. Rapid weight loss, whether from drugs or diet, can cause some muscle loss unless countered. These drugs are prescription medicines with side effects and medical considerations; retatrutide in particular is experimental and not approved for general use. If you’re thinking about starting one of these medications and want to preserve muscle, talk with your doctor and a trainer or dietitian to set up a suitable protein and lifting plan and to monitor side effects. Bottom line: people have kept or built glutes on these drugs when they maintained targeted lifting and protein, but results vary and careful planning plus medical guidance are important.
Source: r/Peptides