The Claim

In well-trained male kayak sprint athletes, both resistance-type and paddling-based high-intensity interval training increase the testosterone-to-cortisol ratio without significantly altering absolute testosterone or cortisol levels.

Source: Effects of a New Form of Resistance-Type High-Intensity Interval Training on Cardiac Structure, Hemodynamics, and Physiological and Performance Adaptations in Well-Trained Kayak Sprint Athletes

What the research says

Supports is higher

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

Supports
62score
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

In well-trained male kayak sprinters, two types of high-intensity training raise the ratio of testosterone to cortisol without changing the total amounts of either hormone.

See the scientific wording

In well-trained male kayak sprint athletes, both resistance-type and paddling-based high-intensity interval training increase the testosterone-to-cortisol ratio, suggesting a shift toward an anabolic hormonal environment, though neither training modality significantly altered absolute testosterone or cortisol levels.

Why this might work

Intense exercise activates the brain's hormone control center, which signals the testes to produce more testosterone. At the same time, the stress hormone cortisol stays the same. This makes the balance between testosterone and cortisol shift in favor of muscle building.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: Effects of a New Form of Resistance-Type High-Intensity Interval Training on Cardiac Structure, Hemodynamics, and Physiological and Performance Adaptations in Well-Trained Kayak Sprint Athletes

    In elite kayak athletes, both intense weight training and intense paddling workouts made the balance of two key hormones favor muscle growth, without changing the total amounts of those hormones — just like the claim says.

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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