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Study · Measured the body's own peptide · 2008

3 results

Acute changes in endocrine and fluid balance markers during high-intensity, steady-state, and prolonged endurance running: unexpected increases in oxytocin and brain natriuretic peptide during exercise.

Hew-Butler T, Noakes TD, Soldin SJ, Verbalis JG

European journal of endocrinology15 Sept 2008Cited by 77 (Europe PMC)

PMID18794210 (opens in a new tab)DOI10.1530/eje-08-0064 (opens in a new tab)PepBankPUB-18794210
Publisher pagePubMedAsk about this study
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Summary

The text of this summary is not shown here, because the article license does not allow reuse. Read it at the source (opens in a new tab)

Text rights: Publisher copyright. Results still quote short attributed sentences.

Results from this study3

No result from this study comes from a test of the peptide.

Natural levels measured3

These results measure the body's own peptide. Nobody was given the peptide. They are not evidence about taking it. They are left out of key results, evidence counts and charts.

  1. 01HumanEndogenous levelObservational studyOther

    In seven endurance-trained runners, plasma oxytocin rose significantly from before to after a 56 km ultramarathon.

    In plain wordsIn endurance runners, the body's own oxytocin level rose after a 56 km ultramarathon.

    Peptide
    Oxytocin
    Outcome
    IncreasePlasma oxytocin change after 56 km ultramarathon
    Study

    n = 7

    Outcome group
    Exercise and physical function · Endocrine and hormones

    Measurements

    Plasma OT pre-run
    1.5 pg/ml
    ultramarathon
    Plasma OT post-run
    3.5 pg/ml
    ultramarathon

    Source sentences

    Summary
    [OT](p) (1.5 vs 3.5 pg/ml; P<0.05)
    1 context sentence
    Summary · context
    Seven endurance-trained runners completed three separate running trials: a maximal test to exhaustion (high intensity), a 60-min treadmill run (steady state), and a 56 km ultramarathon (prolonged endurance exercise).

    This result measures the body's own Oxytocin. Nobody was given the peptide. It is not evidence about taking it.

  2. 02HumanEndogenous levelObservational studyOther

    In seven endurance-trained runners, plasma oxytocin did not rise significantly after a maximal test to exhaustion or a 60-minute steady-state run; significant increases were found only after the ultramarathon.

    In plain wordsIn endurance runners, the body's own oxytocin level did not rise significantly after a short hard run or a 60-minute run.

    Peptide
    Oxytocin
    Outcome
    No significant changePlasma oxytocin change after high-intensity and steady-state running
    Study

    n = 7

    Outcome group
    Exercise and physical function · Endocrine and hormones

    Source sentences

    Summary
    Statistically significant pre- to post-run increases were found only following the ultramarathon in
    1 context sentence
    Summary · context
    Seven endurance-trained runners completed three separate running trials: a maximal test to exhaustion (high intensity), a 60-min treadmill run (steady state), and a 56 km ultramarathon (prolonged endurance exercise).

    This result measures the body's own Oxytocin. Nobody was given the peptide. It is not evidence about taking it.

  3. 03HumanEndogenous levelObservational studyOther

    In seven endurance-trained runners, plasma oxytocin correlated positively with plasma arginine vasopressin.

    In plain wordsIn endurance runners, higher natural oxytocin levels went together with higher vasopressin levels.

    Peptide
    Oxytocin
    Outcome
    IncreaseCorrelation of plasma oxytocin with plasma AVP
    Study

    n = 7

    Outcome group
    Exercise and physical function · Endocrine and hormones

    Measurements

    r
    0.69
    OT versus AVP

    Source sentences

    Summary
    Hypothetically driven relationships between [OT](p) and [AVP](p) (r=0.69; P<0.01)
    1 context sentence
    Summary · context
    Seven endurance-trained runners completed three separate running trials: a maximal test to exhaustion (high intensity), a 60-min treadmill run (steady state), and a 56 km ultramarathon (prolonged endurance exercise).

    This result measures the body's own Oxytocin. Nobody was given the peptide. It is not evidence about taking it.

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

Version history

PepBank keeps every version of the data on this study. Status changes from Retraction Watch, Europe PMC and Crossref are listed with their source.

  1. Version 2Current

    11 Oct 2026, 01:30 UTC

    Study results updated

  2. Version 1

    9 Oct 2026, 02:52 UTC

    First added · source update from Europe PMC

Subjects

Terms as the source lists them.

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