The Claim

In untrained young adults, comparing eccentric tempo of 2 seconds versus 4 seconds during unilateral knee extension exercises does not meaningfully affect gains in one-repetition maximum (1RM) strength, despite the difference in time under tension.

Source: Effect of different eccentric tempos on hypertrophy and strength of the lower limbs

What the research says

Supports is higher

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

Supports
54score
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

If you're a young adult who hasn't trained much before, slowing down the lowering part of a leg extension from 2 seconds to 4 seconds won't make you significantly stronger, even though your muscle is under tension longer.

See the scientific wording

In untrained young adults, eccentric tempo (2s vs 4s) does not meaningfully affect 1RM strength gains in unilateral knee extension, despite differences in time under tension.

What the research says

1 study
  1. Study: Effect of different eccentric tempos on hypertrophy and strength of the lower limbs

    The study had people do leg extensions with either a slow (4-second) or fast (2-second) lowering phase, and found that both groups got just as strong — so slowing down the lowering part didn’t make them stronger.

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

Fit Body Science verdict — we translate health claims into clear verdicts backed by peer-reviewed research.

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