The Claim

In untrained adults, performing single-joint knee extensions (70% 1RM, 5 sets of 10 reps, 2 sessions/week for 12 weeks) is associated with significantly greater rectus femoris hypertrophy (+13.2%) compared to multi-joint leg presses (+1.1%), suggesting that single-joint exercises may be more effective for targeting this specific muscle.

Source: Hypertrophic Effects of Single- versus Multi-Joint Exercise: A Direct Comparison Between Knee Extension and Leg Press.

What the research says

Supports is higher

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

Supports
44score
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.

Quantitative
1 study reviewed
In plain English

For people who don't usually work out, using a knee extension machine grows the front thigh muscle much more than using a leg press machine.

See the scientific wording

In untrained adults, performing single-joint knee extensions (70% 1RM, 5 sets of 10 reps, 2 sessions/week for 12 weeks) is associated with significantly greater rectus femoris hypertrophy (+13.2%) compared to multi-joint leg presses (+1.1%), suggesting that single-joint exercises may be more effective for targeting this specific muscle.

What the research says

1 study
  1. Study: Hypertrophic Effects of Single- versus Multi-Joint Exercise: A Direct Comparison Between Knee Extension and Leg Press.

    The study found that leg extensions built more rectus femoris muscle than leg presses, which matches the claim.

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

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