The Study
Effect of strenuous anaerobic running exercise on plasma growth hormone, cortisol, luteinizing hormone, testosterone, androstenedione, estrone and estradiol.
This study watched what happened to the hormones in five runners after they ran really hard. It saw that some hormones went up and others went down, but it didn't test if running caused those changes — it just saw what happened once.
Analysis score
Maximum 44 for a cross-sectional study.
Where the score came from
After running super hard for a short time, your body releases lots of certain hormones, but then some drop way below normal later.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 538 / 100
Quality score
Snapshots of a population at a single point in time, or descriptions of small groups. Can identify correlations and prevalence, but cannot determine cause and effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1These big swings might mean your body is stressed and recovering — not necessarily bad, but could affect energy, muscle, or recovery if it happens too often.
- 2Growth hormone went up 233%, LH up 49%, testosterone up 13% then down 51% below normal 6 hours later, androstenedione up 34% then down 40% below normal.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Journal of steroid biochemistry
Year
1976
Authors
K. Kuoppasalmi, H. Näveri, S. Rehunen, M. Härkönen, H. Adlercreutz
Related Content
Claims (6)
After a single intense sprinting session, male endurance runners experience immediate increases in plasma growth hormone, luteinizing hormone, testosterone, and androstenedione, followed by a drop in testosterone and androstenedione below baseline levels six hours later.
In a group of five male runners, the fittest runner had larger increases in luteinizing hormone, testosterone, androstenedione, and cortisol after intense running, while the least fit runner had a larger increase in growth hormone.
After a single intense sprint or high-intensity running session, testosterone and androstenedione levels in male runners drop by 51% and 40% within six hours, which is a larger decrease than the 12% drop seen during a regular day of normal activity.
After one intense sprint or high-intensity run, plasma growth hormone levels in male runners rise by 233% immediately and stay elevated for over 24 hours in some cases.
After intense short-duration running, male runners experience a small rise in cortisol hormone levels, and this change follows a similar pattern to estrone, suggesting the adrenal gland's response is less pronounced compared to other hormones measured.
Higher levels of the stress hormone cortisol cause the pituitary gland to release less luteinizing hormone, which results in lower testosterone production by the testes.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.