The Claim

In previously untrained young men, after 15 weeks of lower body resistance training, increases in muscle mass are very strongly associated with gains in isometric knee extension strength (r = 0.92) and one-repetition maximum strength (r = 0.89), indicating that muscle hypertrophy is a primary driver of individual differences in strength gains in this population.

Source: Muscle Growth Is Very Strongly Correlated with Strength Gains after Lower Body Resistance Training: New Insight from Within-Participant Associations

What the research says

Supports is higher

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

Supports
67score
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.

Correlation
1 study reviewed
In plain English

When guys who’ve never lifted weights before train their legs for 15 weeks, the more their muscles grow, the stronger they get—so muscle growth is mostly why they get stronger.

See the scientific wording

In previously untrained young men, muscle growth following 15 weeks of lower body resistance training is very strongly associated with increases in isometric knee extension strength (r = 0.92) and one-repetition maximum strength (r = 0.89), suggesting that hypertrophy is a primary contributor to individual strength gains in this population.

Why this might work

When someone lifts weights, their muscle fibers get thicker because they make more of the proteins that make muscles contract. More of these proteins mean more connections between the parts of the muscle that pull together, so the muscle can push or pull harder. This increase in muscle size is the main reason the person gets stronger.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: Muscle Growth Is Very Strongly Correlated with Strength Gains after Lower Body Resistance Training: New Insight from Within-Participant Associations

    When guys who’ve never lifted before train their legs for 15 weeks, their muscles get bigger—and the more they grow, the stronger they get. This study shows muscle growth is the main reason they get stronger, not just better nerve signaling.

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

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