Six runners ran 32% longer to exhaustion after three weeks of post-training saunas
Claims that a post-workout sauna builds endurance cite this 2007 Journal of Science and Medicine in Sport study. Six competitive male runners trained for three weeks with saunas after their sessions and for three weeks without.
The paper
Effect of post-exercise sauna bathing on the endurance performance of competitive male runners
Scoon GS, Hopkins WG, Mayhew S, Cotter JD. Journal of Science and Medicine in Sport, 2007;10(4):259-262.
See the study at a glance
- Design
- Crossover study without placebo
- People
- 6 male runners
- Who they were
- Competitive male distance runners.
- What they did
- Straight after training, runners sat in a humid sauna at 89.9°C for about 31 minutes. They did this 12.7 times on average over three weeks. The control period had the same training with no sauna, and a three-week washout let any effects fade between the two periods.
- How long
- Two three-week periods with a three-week washout
These numbers came out of it
+32%
After the sauna period, runners held 5-km race pace 32% longer before exhaustion than after the control period.
1.9%
The authors estimated the gain would be worth about 1.9% in an endurance time trial.
+7.1%
Plasma volume (the fluid part of the blood) rose 7.1% after the sauna period. Red cell volume rose 3.5%, and its plausible range (confidence interval) included no change.
0.96
The runners whose plasma volume rose most improved most, and the correlation between the two came to 0.96.
The researchers did this
Six competitive male distance runners did two three-week blocks of their normal training. In one block they took a humid sauna at 89.9°C right after training. They went 12.7 times on average and stayed about 31 minutes.Source 1 · Crossover trialEffect of post-exercise sauna bathing on the endurance performance of competitive male runnersScoon GS, Hopkins WG, Mayhew S, et al.. Journal of Science and Medicine in Sport, 2007.Read the paper ↗PubMed ↗ The other block had no sauna, and three weeks of washout separated the two.
Each runner's test was a treadmill run at his current 5-km race speed until exhaustion. It took about 15 minutes. Runners did it on the first and second days after each block, and the researchers averaged the two results.
After the sauna block the runners lasted 32% longer (90% confidence limits 21% to 43%). By the authors' estimate, that would be worth about 1.9% in an endurance time trial. Plasma volume rose 7.1%, and the size of each runner's rise tracked his improvement closely (r = 0.96).
The study can't tell you these things
- Six runners make a tiny sample.
- Runs to exhaustion stretch small changes in fitness into big percentages. The authors' own time-trial estimate was about 1.9%.
- There was no placebo, and the runners knew when they were taking saunas.
- The abstract doesn't say whether the order of the blocks was randomized.
- All six were men in hard training, and they averaged 12.7 saunas of about half an hour at 90°C in three weeks.
People quote it like this
This is where "a sauna after training boosts endurance 32%" comes from. The figure measures how much longer six runners could keep going before exhaustion, and the authors equated it to about 1.9% in a race-style time trial.Source 1 · Crossover trialEffect of post-exercise sauna bathing on the endurance performance of competitive male runnersScoon GS, Hopkins WG, Mayhew S, et al.. Journal of Science and Medicine in Sport, 2007.Read the paper ↗PubMed ↗
From our sister magazine
Sauna Monthly reviews saunas that reach the 90°C these runners used
We cited these sources
- 01Scoon GS, Hopkins WG, Mayhew S, Cotter JD. Effect of post-exercise sauna bathing on the endurance performance of competitive male runners. Journal of Science and Medicine in Sport. 2007;10(4):259-262. doi:10.1016/j.jsams.2006.06.009 PMID 16877041