Thermal Shield

A standard sauna session (15–20 min at 90–100°C) can push testicular temperature toward 38–39°C, well above their normal 33–35°C, because the heat overwhelms the scrotum's natural cooling. This temporarily impairs sperm production and fertility, one of the best-documented effects of testicular heat.

Leydig cells, which produce about 95% of your testosterone, also work best at that cooler range, so repeated heat isn't ideal for them. It acts through three linked mechanisms:

1. Reduced steroidogenesis, heat downregulates the enzymes that build testosterone (StAR, P450scc, 3β-HSD, 17β-HSD), lowering output.
2. Oxidative stress, reactive oxygen species damage cellular machinery and accelerate wear.
3. Apoptosis, strong or prolonged heat can trigger cell death, shrinking the testosterone-producing cell population.

Together these point toward potentially reduced testosterone capacity over time, alongside the better-documented effect on sperm. Saunawear keeps the testicles closer to their natural cool range during sauna use, so you get the heat without the trade-off.

Yes, this is the most established part of the science. Sperm production needs a temperature a few degrees below body heat, and sauna heat pushes well above that, temporarily lowering sperm count and motility. The good news: it's largely reversible. Because the sperm cycle takes about 74 days, effects typically recover over weeks to months once the heat stress is removed. If you're trying to conceive, reducing testicular heat is a sensible, well-supported precaution.

Not effectively. A cold shower cools your skin afterward, but the goal is to limit how hot the testicles get during the heat, and a post-sauna plunge doesn't undo the temperature rise that already happened. Cooling at the source, during exposure, is what keeps them in range. That's the gap Saunawear fills.

This matters more in a sauna than anywhere else, because heat and heavy sweating are exactly where cheap synthetics shed microplastics and release chemicals against your skin.

Saunawear is 92% TENCEL and 8% elastane. TENCEL is a plant-based fibre from sustainably sourced wood pulp, chosen deliberately for the sauna:

• Natural, not plastic. Cellulosic and biodegradable, so it doesn't shed plastic microfibres as it heats and is sweated into.
• Optimised moisture-wicking. Moves sweat better than cotton or synthetics, keeping skin drier.
• Anti-bacterial and fresh. Naturally resists odour-causing bacteria, session after session.
• Second-skin feel. Smooth, breathable, and silky-soft, with no chafing.

The 8% elastane gives the supportive, no-slip fit that keeps it in place. It's synthetic but fully tested: our fabric is certified to OEKO-TEX Standard 100, Product Class I, the strictest tier (the same applied to baby products), so it's verified safe for prolonged skin contact and sauna use.

It's simple. Freeze the cooling pack ahead of time, slot it into the pocket of your Saunawear, and wear the garment under your usual shorts or swimwear. The pack sits in the cooling zone and absorbs the heat for a full session. When you're done, take the pack out, refreeze it, and you're set for next time. For back-to-back sessions, just swap in a fresh frozen pack.

No, that's the point. The recovery benefits you're after (heat shock proteins, cardiovascular adaptation, relaxation) come from heating your whole body, not your testicles. Saunawear only keeps that one small, heat-sensitive area cooler, so your muscles get the full effect while your reproductive organs are spared the unnecessary stress. You get both in one session.

The more often and longer you sauna, the more it matters. A rare session is low-risk and largely reversible. But if sauna is a regular habit, several times a week over years, the case for keeping cool gets stronger, because the open question is whether repeated heat with incomplete recovery adds up. If you sauna often or care about fertility and hormonal health, it's worth building in.

No. It looks and fits like lightweight compression boxers and sits seamlessly under boardshorts, swimwear, or gym shorts. No bulk, no visible outline.

The opposite, and it's what users tell us surprised them. There's no cold shock and nothing harsh against the skin, the fabric sits between the cooling element and your body, so you never feel direct ice, just a comfortable, neutral coolness in the middle of the heat. It's gentle and safe for the sensitive area it protects. Most people say it makes the sauna more enjoyable: you relax, stay in longer, and stay protected throughout.

Yes, cold or mild cycle, max 30°C. Avoid bleach, harsh chemicals, and tumble drying to protect the elasticity and fabric.