------|-------------------------|-------------------| | Total weight loss | 22.1% | ~15% | | Fat mass loss | 92.8% of weight | ~65% of weight | | Lean mass loss | 7.2% of weight | ~35% of weight | | Visceral fat reduction | 58% | ~45% |
Translation: - Semaglutide alone: Lose 30 lbs, ~11 lbs is lean mass - With bimagrumab: Lose 30 lbs, ~2 lbs is lean mass
That's a massive difference for men who care about muscle.
Why This Matters for Men
The Muscle Loss Fear
The #1 objection men raise about GLP-1s is muscle loss. "I don't want to get skinny-fat." "I'll lose everything I built."
BELIEVE proves this is solvable. Muscle loss on GLP-1s isn't destiny — it's a problem with a pharmaceutical solution.
More Weight Loss Too
Not only did the combination preserve muscle, it produced MORE total weight loss (22.1% vs ~15%). Less lean mass loss AND more fat loss.
Better Body Composition
The final body composition is dramatically different: - Semaglutide alone: Lighter, but higher body fat percentage - With bimagrumab: Lighter AND more muscular composition
This is the "recomp" that's so hard to achieve naturally.
The Catch: Availability
Bimagrumab is not yet FDA-approved for this use. The BELIEVE data is recent. Timeline for availability:
- Phase 3 trials: Ongoing/planned
- FDA approval: Likely 2026-2027 if trials succeed
- Availability: Unknown, depends on approval and pricing
For now, bimagrumab is experimental. But knowing it works changes the conversation.
What This Means for Today
While waiting for bimagrumab:
The principle still applies
Active muscle preservation works. Bimagrumab is pharmaceutical-grade muscle preservation, but resistance training is available now.
Resistance training is the accessible version
You don't have bimagrumab. You do have a gym. Lifting weights sends similar signals (to a lesser degree) — preserve muscle, prioritize fat loss.
Protein remains critical
Bimagrumab participants still needed adequate protein. No muscle-preserving intervention works without amino acids to build/maintain tissue.
Future combinations are coming
This won't be the only muscle-preserving combination. Other myostatin inhibitors, other mechanisms — the pipeline is active.
For the Skeptics
"If you need a second drug to prevent side effects of the first drug, isn't that a problem?"
Consider: - Many treatments require combinations (chemotherapy, HIV treatment) - The combination produces better outcomes than either alone - The "side effect" (lean mass loss) occurs with ALL weight loss methods, not just GLP-1s - Bimagrumab addresses a universal weight loss challenge, not a GLP-1-specific one
Future Implications
For men considering GLP-1s now
Don't wait for bimagrumab. The benefits of fat loss available today outweigh the lean mass concerns — especially with proper training and protein. Start now, optimize muscle preservation with available methods.
For men starting GLP-1s in 2027+
You may have access to combination therapy that makes muscle loss a non-issue. The treatment is likely to get even better.
For the fitness industry
Combination GLP-1 + muscle-preserving agents may become standard for men seeking body recomposition. The "drugs make you skinny-fat" criticism is being solved.
For drug development
BELIEVE validates the combination approach. Expect more trials exploring GLP-1s + anabolic/anti-catabolic agents.
The Bottom Line
BELIEVE proved that muscle loss on GLP-1s is: - Not inherent to the drugs - Addressable with the right combination - Reducible from ~35% of weight to ~7% of weight
For men, this is the data we needed. The fear of "losing all your gains" has a pharmaceutical answer in development. The optimal treatment is coming.
Until then: lift, eat protein, and know that the future of GLP-1 treatment is muscle-sparing.
Related Articles: - The Muscle Loss Question: Real vs Hype - The GLP-1 Lifting Protocol - Protein Requirements on GLP-1s
Last updated: January 2026
Sources: ADA 2025 presentation; BELIEVE trial data
Medical disclaimer: Bimagrumab is not FDA-approved for this use. This article discusses experimental data.