The Claim

In 86% of training-overload or overtraining syndrome (OTS) studies that assessed energy or carbohydrate availability, there was evidence of reduced energy or carbohydrate availability during the overload period, indicating that low fuel availability is commonly observed when OTS symptoms emerge in endurance athletes.

Source: Overtraining Syndrome (OTS) and Relative Energy Deficiency in Sport (RED-S): Shared Pathways, Symptoms and Complexities

What the research says

Roughly balanced

Support and challenge are close. The picture may shift as more studies come in.

Supports
1score
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

Most studies on overtrained endurance athletes found they weren’t eating enough carbs or energy when their symptoms started — so running low on fuel might be a common factor.

See the scientific wording

In 86% of training-overload or OTS studies that measured energy or carbohydrate availability, there was evidence of reduced energy or carbohydrate availability during the overload period, suggesting that low fuel availability is commonly present when OTS symptoms develop in endurance athletes.

What the research says

1 study

  1. Study: Overtraining Syndrome (OTS) and Relative Energy Deficiency in Sport (RED-S): Shared Pathways, Symptoms and Complexities

    The study looked at other research on overtrained athletes and found that most of them weren’t eating enough calories or carbs, which matches the claim.

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.

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