The Claim

In untrained young adults, performing squats with a 4-second eccentric tempo increases time under tension compared to a 1-second eccentric tempo, despite lower total repetitions and reduced training volume.

Source: The effects of eccentric phase tempo in squats on hypertrophy, strength, and contractile properties of the quadriceps femoris muscle

What the research says

Supports is higher

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

Supports
68score
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

When untrained young adults perform squats with a slower lowering phase lasting 4 seconds, the muscles experience more total tension over time than when the lowering phase lasts only 1 second, even though they do fewer repetitions and less overall work.

See the scientific wording

In untrained young adults, a 4-second eccentric tempo during squats results in significantly greater time under tension than a 1-second tempo, despite producing fewer total repetitions and lower training volume, indicating that tempo manipulation can independently alter training stimulus.

Why this might work

When you lower a weight slowly, your muscles stay under tension longer, which forces the endurance-type muscle fibers to grow bigger and work more efficiently, making you stronger even if you do fewer reps.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: The effects of eccentric phase tempo in squats on hypertrophy, strength, and contractile properties of the quadriceps femoris muscle

    Slowing down the downward part of squats made muscles grow more and get stronger, even though people did fewer reps — proving that how slowly you move matters, not just how many times you do it.

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

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