Christchurch , The internet’s obsession with “maxxing” has turned almost every aspect of self-improvement into a trend.
But how much of this advice is actually supported by evidence? And could some of these popular wellness practices have the opposite effect to the one intended? Where hype meets evidence Saunas or cold plunges may indeed improve sleep, reduce stress or support general wellbeing. But those benefits should not be confused with evidence of improved fertility. Exposure to extreme temperatures was associated with poorer semen quality, including lower sperm concentration, total count and motility. the findings support broader evidence that heat can disrupt sperm production While hot weather and sauna use are clearly different. Another US-led study followed couples trying to conceive. Hot baths and hot tubs alone had little effect on pregnancy rates. But men with greater cumulative exposure to multiple heat sources had moderately lower chances of conception.
A large 2024 study followed more than 15,000 Chinese men and analysed over 28,000 semen samples. Perhaps the strongest evidence on saunas comes from an Italian longitudinal study, in which ten healthy men completed two 15-minute Finnish sauna sessions each week at 80-90°C for three months.
