The Claim

In heavy resistance-trained male youth rugby league players, higher-volume hypertrophy training using loads of 35–70% 1RM is associated with greater declines in field-specific performance compared to lower-volume maximal strength training using loads of 70–100% 1RM, with observed performance reductions of 2.1% in 20 m sprint time and 1.1% in agility performance at both 24 and 48 hours post-training.

Source: The Acute Effect of Increasing Resistance Training Workload Volume on Muscle Damage Markers and Performance in Heavy Resistance-Trained Youth Athletes

What the research says

Supports is higher

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

Supports
33score
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

In young male rugby players who lift weights, doing high-rep, lighter weight workouts leads to worse sprinting and agility performance for up to two days compared to low-rep, heavy weight workouts.

See the scientific wording

In heavy resistance-trained male youth rugby league players, higher-volume hypertrophy training (35–70% 1RM) is associated with greater declines in field-specific performance compared to lower-volume maximal strength training (70–100% 1RM), including a 2.1% decline in 20 m sprint time and a 1.1% decline in agility performance at 24 and 48 hours post-training.

What the research says

1 study
  1. Study: The Acute Effect of Increasing Resistance Training Workload Volume on Muscle Damage Markers and Performance in Heavy Resistance-Trained Youth Athletes

    The study shows that when young rugby players switch from heavy strength training to higher-rep, lighter-weight training, their speed and agility get worse for a couple of days afterward, just like the claim says.

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

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