Peer-reviewed research concerning sauna & heat, summarized and appraised in plain language with every source cited.
This review looked at whether the underwear a man wears, tight versus loose, actually affects his fertility. The testicles work best a little cooler than the rest of the body,…
This study compared two ways of making sprint training harder: doing it in thin air, and doing it in the heat. Healthy men and women trained twice a week for…
This study looked at how occupational heat exposure and fertility-related stress might affect semen quality. It compared 485 men, split into groups with normal and low semen quality based on…
This study measured how outdoor temperature tracks with semen quality, using records from 5,114 men attending a reproductive medicine centre in Wenzhou, on China's east coast. The measure it used…
This study set out to see if sperm quality changes with the seasons in Denmark and Florida, and whether outdoor temperatures play a role. It looked at semen samples from…
This study asked whether the pandemic changed how sensitive sperm production is to weather. It took 2,672 semen analyses from 1,287 Korean men collected between 2018 and 2024 and matched…
This study measured what happens to scrotal temperature during a run. Eleven trained long-distance runners ran on a treadmill for 60 minutes at 60% of their maximum aerobic capacity, in…
This review gathers recent evidence on what damages male fertility and how much of it can be undone. Smoking raises sperm DNA fragmentation (breaks in the genetic material inside sperm)…
This study asked which workplace exposures matter most for men's reproductive health. It took 80 men working in an automobile parts plant, measured their exposure to magnetic fields, electric fields,…
This study looked at how the smallest blood vessels in the skin respond to a hot bath, and whether that differs by ethnicity. Thirty-one healthy young men (10 White-European, 10…
This study tested whether making training harder by adding heat, thin air, or both improves short-burst cycling power. Eighty untrained young men were split into five groups of 16: no…
This study followed 2,575 Finnish men aged 42 to 61 for a median of 27.8 years and asked whether sauna habits change how dangerous high blood pressure is. Over that…
This study looked at whether adding sauna sessions after exercise affects gut bacteria, intestinal barrier function, and inflammation in young men. Fifteen untrained men were split into two groups: one…
This review pulled together what is known about how everyday life affects a man's fertility, covering age, psychological stress, nutrition, physical activity, caffeine, scrotal temperature, hot water and mobile phone…
This is a history of forty years of French research into male contraception (hormonal, chemical and thermal) summarising clinical trials involving thousands of men and couples. Those trials established that…