The Claim

Leucine supplementation at 5 grams three times daily with meals does not attenuate the decline in daily muscle protein synthesis rates or prevent loss of quadriceps muscle mass during three days of unilateral leg immobilization in healthy young and older adults.

Source: Leucine supplementation does not attenuate the decline in daily muscle protein synthesis rates or preserve leg muscle mass during leg immobilization in young or older adults: a double-blind randomized trial

What the research says

Supports is higher

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

Supports
81score
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.

Cause and effect
1 study reviewed
In plain English

Taking 5 grams of leucine three times a day with meals does not stop the decrease in muscle protein synthesis or prevent muscle loss in the quadriceps during three days of leg immobilization in healthy young and older adults.

See the scientific wording

Leucine supplementation at 5 grams three times daily with meals does not attenuate the decline in daily muscle protein synthesis rates or prevent loss of quadriceps muscle mass during three days of unilateral leg immobilization in healthy young and older adults, indicating that acute leucine dosing is insufficient to counteract disuse-induced anabolic resistance in this context.

Why this might work

When leucine is taken with meals, it enters the bloodstream and signals muscle cells to start making more protein. But when a leg is immobilized, muscle cells become resistant to this signal. Even though leucine is present and the signaling pathway turns on, the muscle cells do not increase protein production enough to stop muscle loss.

Supported mechanismbased on 1 study

What the research says

1 study
  1. Study: Leucine supplementation does not attenuate the decline in daily muscle protein synthesis rates or preserve leg muscle mass during leg immobilization in young or older adults: a double-blind randomized trial

    Taking leucine pills three times a day with meals didn't help stop muscle loss or slow muscle breakdown in people whose legs were immobilized for three days — whether they were young or old.

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

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Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.