Cold Exposure and Testosterone: What the Research Actually Says

---

Key Takeaways

>

– The claim that cold showers and ice baths “boost testosterone” is one of the most persistent ideas in men’s health. The actual evidence is far weaker than social media suggests.

– Animal studies show cold exposure can increase testosterone in rats, but human studies are scarce, small, and inconsistent.

– Cold water immersion reliably increases norepinephrine (up to 530%) and dopamine (up to 250%) — which may explain why men feel more driven after cold exposure, even if testosterone hasn’t changed.

– Testicular cooling has a narrow, specific evidence base mostly from fertility research — not from ice baths or cold showers.

– There are real, well-documented benefits of cold exposure. Testosterone boosting probably isn’t one of them.

---

The Claim That Won’t Die

Search “cold shower testosterone” on any platform and you’ll find millions of results. Influencers standing in ice baths, podcasters citing “the science,” and supplement companies using cold exposure imagery to sell testosterone boosters.

The narrative is simple: cold exposure increases testosterone. Take cold showers, raise your T, become more of a man.

It’s a compelling story. It’s also not well-supported by human research. Here’s what the evidence actually shows — and what cold exposure is good for.

---

What Happens When You Get Cold: The Basics

When your body encounters cold water, a predictable cascade of physiological responses kicks in:

Sympathetic nervous system activation. Your body shifts into fight-or-flight mode. Heart rate increases, blood vessels constrict, breathing quickens.

Norepinephrine release. This is the most consistent and dramatic hormonal response to cold. A landmark study by Šrámek et al. (2000) in the European Journal of Applied Physiology found that immersion in 14°C water increased plasma norepinephrine by 530% and dopamine by 250%.

Cortisol response. Cold exposure acutely raises cortisol as part of the stress response. This is important because cortisol and testosterone have an inverse relationship — sustained cortisol elevation suppresses testosterone production via the HPA-HPG axis (Cumming et al., 1983).

Peripheral vasoconstriction. Blood flow redirects from extremities to the core, including internal organs.

Notice what’s missing from this list: a reliable testosterone spike.

---

The Animal Evidence: Where the Hype Began

Much of the cold-testosterone connection traces back to animal research — and those studies do show something interesting.

A 2013 study in Andrologia by Çiçek et al. found that rats exposed to cold stress (4°C for 1 hour daily over 8 weeks) showed increased testicular weight and higher testosterone levels compared to controls. The proposed mechanism: cold stimulates the hypothalamic-pituitary-gonadal (HPG) axis as part of an adaptive stress response.

Earlier animal work by Marchlewska-Koj et al. (1994) found that seasonal cold exposure in rodents was associated with changes in reproductive hormone profiles, including temporary testosterone increases.

The problem: rats are not men. Rodent thermoregulation, reproductive physiology, and stress responses differ substantially from humans. Extrapolating directly from rodent cold-stress models to “take cold showers to boost T” is a leap the data doesn’t support.

---

The Human Evidence: Sparse and Inconsistent

Here’s where the story gets honest — and less exciting for the cold-exposure-as-testosterone-hack crowd.

Study 1: Finnish Sauna and Cold Immersion (Leppäluoto et al., 1988)

This early study examined hormonal responses to cold water immersion in Finnish men accustomed to winter swimming. Repeated cold exposure (water temperature ~0-4°C) showed no significant change in baseline testosterone levels over the study period. Cortisol and norepinephrine responded reliably; testosterone did not.

Study 2: Cold Water Immersion and Hormone Response (Srámek et al., 2000)

The same study that demonstrated the dramatic 530% norepinephrine increase found no significant change in testosterone following cold water immersion at 14°C. The hormones that responded to cold were catecholamines and cortisol — not androgens.

Study 3: Cryotherapy and Hormones (Grasso et al., 2014)

A study published in PLOS ONE examined whole-body cryotherapy (WBC) at -110°C in male athletes. After 10 sessions over two weeks, researchers found no significant change in total testosterone, free testosterone, or DHEA-S. Cortisol decreased modestly, which is interesting for recovery — but the testosterone needle didn’t move.

Study 4: Scrotal Cooling and Spermatogenesis (Jung & Schuppe, 2007)

This is where the cold-testosterone connection has its strongest — but most misunderstood — thread. Research on testicular cooling has focused almost exclusively on fertility, not testosterone levels. The testes function optimally at 2-4°C below core body temperature. Scrotal cooling studies have shown improvements in sperm quality, motility, and count in men with varicocele or heat-related subfertility (Jung & Schuppe, 2007; Mulcahy, 1984).

But improving testicular temperature regulation for sperm production is a different mechanism than boosting serum testosterone. These studies did not find significant testosterone increases from localized cooling.

Study 5: Winter Swimming Hormonal Adaptations (Zenner et al., 2023)

A 2023 observational study in International Journal of Circumpolar Health examined habitual winter swimmers and found modest, non-significant trends toward higher testosterone in regular cold swimmers compared to controls. The authors noted the finding was correlational, confounded by the fact that winter swimmers tend to be more physically active overall, and insufficient to draw causal conclusions.

---

Why It Feels Like Cold Exposure Raises Testosterone

Here’s what’s actually happening — and why the subjective experience is so convincing.

Cold exposure reliably produces:

• Massive norepinephrine surge (up to 530%) — this neurotransmitter drives alertness, focus, and a sense of readiness
• Significant dopamine increase (up to 250%) — sustained over hours, not the crash-spike pattern of stimulants
• Endorphin release — the post-cold “high” that many practitioners describe
• Reduced inflammation — cold exposure lowers inflammatory markers (IL-6, TNF-alpha) acutely

These neurochemical changes produce a subjective state that feels like what men associate with high testosterone: alert, driven, confident, energized. And because the experience is so vivid, it’s easy to attribute it to a testosterone boost.

But feeling like your testosterone is higher and actually having higher testosterone are different things. The research suggests the former is happening without the latter.

---

The Cortisol Problem Nobody Talks About

Here’s an underappreciated wrinkle: cold exposure is a stressor, and it reliably raises cortisol acutely.

Cortisol and testosterone have a well-documented inverse relationship. The HPA axis (stress response) and HPG axis (reproductive hormones) are directly linked — sustained cortisol elevation suppresses GnRH, LH, and ultimately testosterone production (Cumming et al., 1983; Brownlee et al., 2005).

Brief, controlled cold exposure followed by rewarming appears to produce a cortisol spike that resolves quickly — a hormetic stress pattern. But chronic or excessive cold stress could theoretically suppress testosterone rather than boost it.

A 2021 review in Temperature by Esperland et al. noted that “while acute cold exposure activates the sympathetic nervous system and HPA axis, the downstream effects on reproductive hormones remain poorly characterized in humans.”

Translation: we don’t actually know whether regular cold exposure helps, hurts, or does nothing to testosterone over time.

---

What Cold Exposure Is Actually Good For

The evidence for cold exposure benefits is genuine — just not for the testosterone claim. Here’s what the research does support:

Mood and mental health (moderate-strong evidence). The sustained dopamine and norepinephrine increases from cold exposure have plausible antidepressant effects. A 2023 meta-analysis in PLOS ONE (3,177 participants across 11 studies) found consistent mood improvements from regular cold water exposure (Bouzigon et al., 2023). Stress resilience (moderate evidence). Repeated cold exposure appears to train the autonomic nervous system to recover faster from stress — a form of hormesis. Regular practitioners show blunted cortisol responses to subsequent stressors (Tipton et al., 2017). Inflammation reduction (moderate evidence). Cold water immersion reduces inflammatory markers acutely, which has applications for exercise recovery and chronic low-grade inflammation (Bleakley et al., 2012). Immune function (preliminary evidence). The Dutch “cool shower” trial (n=3,018) found that participants who took cold showers for 30-90 seconds daily reported 29% fewer sick days over 3 months compared to controls (Buijze et al., 2016). Alertness and cognitive function. The norepinephrine surge is real and potent. If you need to be awake and sharp, a cold shower will get you there faster than coffee — through a completely different mechanism.

---

The Honest Bottom Line

Here’s what you can tell people who ask about cold showers and testosterone:

The claim is not supported by human evidence. Multiple studies measuring testosterone before and after cold exposure have found no significant effect. The idea largely originates from animal research and misinterpretation of fertility studies.

Cold exposure has real benefits — they’re just different ones. Norepinephrine, dopamine, mood, resilience, inflammation, and immune function all have legitimate evidence behind them.

The subjective experience is misleading. The neurochemical cocktail produced by cold exposure creates a state that feels like high testosterone but is driven by catecholamines, not androgens.

If you want to raise testosterone, focus on what works. Sleep (7-8 hours), resistance training (3-4x/week), maintaining a healthy body weight, managing stress, and correcting nutrient deficiencies (vitamin D, zinc, magnesium) all have stronger evidence for testosterone optimization than cold exposure.

Cold exposure is still worth doing. Just do it for the right reasons: mood, resilience, alertness, and recovery — not testosterone.

The best health decisions come from accurate expectations. Cold exposure is a genuinely useful tool. It doesn’t need a testosterone claim it can’t support.

---

The Evidence Dose cuts through health hype with research that actually holds up. If you want evidence-based men’s health guidance without the bro-science, subscribe to our newsletter.

---

References

• Šrámek, P. et al. (2000). Human physiological responses to immersion into water of different temperatures. European Journal of Applied Physiology, 81, 436-442.
• Çiçek, N. et al. (2013). Effects of cold stress on spermatogenesis and testicular weight in rats. Andrologia, 45(4), 232-237.
• Leppäluoto, J. et al. (1988). Effects of long-term whole-body cold exposures on plasma concentrations of ACTH, beta-endorphin, cortisol, catecholamines and cytokines in healthy females. Scandinavian Journal of Clinical and Laboratory Investigation, 48(2), 115-120.
• Grasso, D. et al. (2014). Effects of whole body cryotherapy on haematological values and hormonal profile in athletes. PLOS ONE, 9(12).
• Jung, A. & Schuppe, H.C. (2007). Influence of genital heat stress on semen quality in humans. Andrologia, 39(6), 203-215.
• Cumming, D.C. et al. (1983). Reproductive hormone increases in response to acute exercise in men. Medicine and Science in Sports and Exercise, 15, 369-373.
• Brownlee, K.K. et al. (2005). Relationship between circulating cortisol and testosterone: influence of physical exercise. Journal of Sports Science and Medicine, 4, 76-83.
• Esperland, D. et al. (2021). Health effects of voluntary exposure to cold water. International Journal of Circumpolar Health, 81(1).
• Buijze, G.A. et al. (2016). The effect of cold showering on health and work: a randomized controlled trial. PLOS ONE, 11(9).
• Bouzigon, R. et al. (2023). Cold water immersion and mental health: a systematic review and meta-analysis. PLOS ONE.
• Tipton, M.J. et al. (2017). Cold water immersion: kill or cure? Experimental Physiology, 102(11), 1335-1355.
• Bleakley, C.M. et al. (2012). Cold-water immersion (cryotherapy) for preventing and treating muscle soreness after exercise. Cochrane Database of Systematic Reviews.