Fit Body ScienceEvidence-based fitness analysis

After a very intense one-minute bike ride, the stress hormone cortisol in your blood rises after about 15 minutes. This shows that extreme exercise makes your body release cortisol later.

See the scientific wording

In a group of six healthy subjects, plasma cortisol levels increased significantly from a resting mean of 0.40 μmol/L to 0.52 μmol/L at 15 minutes after a one-minute bout of high-intensity cycling exercise at 120% of maximal oxygen uptake, indicating that such exercise is associated with a delayed adrenal cortisol response.

Supporting1 study

Indication only — weak evidence

Observational

One low-scoring study points this way, but the evidence is still early.

What the research says

1 study reviewed

Supporting (1)

None

Contradicting (0)

None

No contradicting studies found yet

That doesn't mean it's settled — it just means no study has tested the opposite.

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Why this might work

When you exercise very hard, your brain notices stress and sends a signal to a gland in your brain to release a hormone called ACTH. This hormone travels in your blood to your adrenal glands (located on top of your kidneys). The adrenal glands then make and release cortisol, a stress hormone, into your blood. This process takes a few minutes, so cortisol levels rise after the exercise ends.

Suggested mechanismbased on 1 study

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

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