The Claim

Three days of unilateral leg immobilization in healthy young men (aged 22 ± 1 years) reduces quadriceps muscle volume by approximately 2.0–2.7% and decreases daily myofibrillar protein synthesis rates by 26–30% compared to the non-immobilized leg, indicating rapid muscle deconditioning occurs independently of dietary protein intake.

Source: Dietary protein intake does not modulate daily myofibrillar protein synthesis rates or loss of muscle mass and function during short-term immobilization in young men: a randomized controlled trial.

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
60score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

How it works
1 study reviewed
In plain English

In healthy young men, three days of immobilizing one leg causes a measurable reduction in quadriceps muscle size and a decrease in the rate of muscle protein synthesis compared to the unimmobilized leg, showing muscle loss occurs without changes in protein intake.

See the scientific wording

Three days of unilateral leg immobilization in healthy young men (aged 22 ± 1 years) reduces quadriceps muscle volume by approximately 2.0–2.7% and decreases daily myofibrillar protein synthesis rates by 26–30% compared to the non-immobilized leg, indicating rapid muscle deconditioning occurs independently of dietary protein intake.

Why this might work

When a muscle is not used, the lack of stretching and pulling forces stops the signals that tell the muscle to build new proteins. Without these signals, the muscle stops making the fibers that make it strong, and the existing fibers break down faster than they are replaced, causing the muscle to shrink.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: Dietary protein intake does not modulate daily myofibrillar protein synthesis rates or loss of muscle mass and function during short-term immobilization in young men: a randomized controlled trial.

    Keeping one leg still for three days made muscles shrink by 2–3% and slowed down muscle building by 26–30%, no matter how much protein the men ate. The study proves this happens even without extra protein.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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