# Measuring strength at Vital Force Peptides

> Vital Force Peptides explores muscle performance, AOD-9604’s failed human weight tests and retatrutide’s clinical results. Strength deserves its own measure.

**Muscle, movement, metabolism**

A muscle held still. An ageing mouse on a treadmill. A falling body weight. Each raises a different question about the work a body can do.

## Holding on in old age

A mouse has to hold on. In the [MOTS-c exercise and ageing study](https://pubmed.ncbi.nlm.nih.gov/33473109/), researchers measured running capacity, grip strength and gait in mice of different ages. Giving MOTS-c improved physical performance, including in old mice. Exercise also increased the peptide the mice produced themselves.

A grip test is a pleasingly literal way into Vital Force Peptides. The muscle has to do something. I give those tasks more weight than a broad promise of vitality because they put an action at the end of the argument: running, gripping, walking. There is room to be impressed by the animal result while the human treatment question remains unanswered.

The word force can describe a measurable pull. Claims about daily energy, recovery or feeling younger spread much further than that. I value an actual test of a body’s ability to work.

## Muscle during immobilisation

Movement also matters through its absence. A [2024 study in mice and cell-free systems](https://pubmed.ncbi.nlm.nih.gov/39559755/) identified casein kinase 2, or CK2, as a direct binding target of MOTS-c. In immobilised mice, MOTS-c reduced muscle wasting. Glucose is the sugar muscle can use as fuel.

The protein’s activity increased in muscle but decreased in fat, so the effects varied by body part. The strength question draws me toward enforced rest. It asks whether a muscle can retain more of itself when movement is restricted. The result earns further research into disuse; human strength, recovery and everyday stamina still need treatment trials in people.

## Weight change and physical capacity

The other research histories pull in different directions. [AOD-9604 increased fat oxidation and reduced weight in obese mice](https://pubmed.ncbi.nlm.nih.gov/11673763/), yet the intended benefit failed to emerge convincingly in human obesity trials. Its growth-hormone origin can make the name sound relevant to muscle; its design was aimed at fat metabolism. The [AOD-9604 page](/aod-9604) follows that narrower ambition.

Retatrutide has much stronger human weight results: [mean body-weight change of -24.2% over 48 weeks at the highest amount tested, versus -2.1% with placebo](https://pubmed.ncbi.nlm.nih.gov/37366315/). Such a large mean change merits close attention. A complete account of physical capacity would also ask about muscle function and life after treatment. The [retatrutide page](/retatrutide) puts the measured weight, glucose and liver findings alongside tolerability and the faster pulse.

## Future physical-function trials

Can a muscle retain function during inactivity? Does a large weight change leave someone moving more easily? How do those changes feel over time? Those are separate endpoints. A human trial giving physical function the same prominence as body weight would be especially welcome.

For now, the [comparison](/compare) separates the outcomes already measured. MOTS-c and AOD-9604 lack FDA approval; retatrutide remains investigational and is undergoing phase 3 testing. Research-labelled material also brings unresolved identity, strength, impurity and sterility questions. None of the studies described here establishes a personal treatment plan. The [questions page](/faq) covers approval, adverse effects and the limits of the evidence.

---

Vital Force Peptides is an independent digest of metabolic signals and measured weight outcomes, not a clinic, vendor, or source of medical direction.