The Claim

In male resistance-trained individuals, overtraining is associated with a 31% decrease in reduced glutathione (GSH), a 56% decline in the GSH/GSSG ratio, and a 25% increase in oxidized glutathione (GSSG), indicating impaired antioxidant defense capacity, which may contribute to performance deterioration during excessive training.

Source: Oxidative stress biomarkers responses to physical overtraining: implications for diagnosis.

What the research says

Supports is higher

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

Supports
25score
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.

How it works
1 study reviewed
In plain English

When guys who lift weights train too much, their body's natural antioxidants take a hit — they lose a lot of the good kind and build up more of the used-up kind, which might be why they start performing worse.

See the scientific wording

In male resistance-trained individuals, overtraining is associated with a 31% decrease in reduced glutathione (GSH), a 56% decline in GSH/GSSG ratio, and a 25% increase in oxidized glutathione (GSSG), indicating impaired antioxidant defense capacity, which may contribute to performance deterioration during excessive training.

What the research says

1 study
  1. Study: Oxidative stress biomarkers responses to physical overtraining: implications for diagnosis.

    The study looked at male weightlifters who trained too hard and found their antioxidant levels dropped and oxidized stress increased, just as the claim says, which helps explain why they performed worse.

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

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