Patrick sleep and heat exposure: The science-backed way to fall asleep faster and sleep deeper

A warm bath, shower, or sauna taken about 1–2 hours before bedtime can help you fall asleep faster and sleep more efficiently by increasing skin blood flow and speeding the post-heat drop in core body temperature. Keep the bedroom cool and use this “heat-then-cool” timing to nudge deeper, more restorative slow-wave sleep for better recovery and sharper mornings.

The relationship

The internet version of “perfect sleep” usually starts and ends with a cold room. That advice is solid, but it misses a useful lever: deliberate heat exposure earlier in the evening. Rhonda Patrick, Ph.D, has popularized a “patrick sleep” approach built around passive heating, then cooling down, to support deeper sleep.

Passive body heating means raising body temperature without exercise, such as a sauna session or hot bath. In a 2019 systematic review and meta-analysis, warm showers or baths taken about 1 to 2 hours before bedtime improved sleep outcomes, including faster sleep onset and better sleep efficiency.^[1]

Why it matters for men: deep sleep is tightly connected to overnight recovery biology, including growth hormone signaling and next-day physical readiness. Slow wave sleep is deep, restorative non-REM sleep that supports tissue repair, immune function, and memory. Patrick’s protocol is aimed at nudging more of that stage by using heat at the right time and dose.

How it works

Warming up to cool down: thermoregulation sets the stage

Your core body temperature is your internal temperature, and it naturally drops in the evening as your circadian rhythm shifts toward sleep. Circadian rhythm is your body’s 24-hour timing system for sleep, hormones, and temperature. Passive heating before bed appears to work partly because it increases heat loss after you get out of the sauna or bath, helping your body cool into sleep.^[1]

This is classic thermoregulation, your body’s control of heat balance. Warm water or sauna heat can increase skin blood flow, which helps transfer heat from your core to the surface, then accelerates cooling afterward.^[2]

Slow wave sleep and growth hormone: the recovery link men feel

Growth hormone is a pituitary hormone that supports tissue repair and metabolic regulation. A large portion of daily growth hormone secretion occurs in the early part of the night and is closely tied to slow wave sleep.^[3]

Patrick highlights an additional angle: growth hormone-releasing hormone, a hypothalamic signal that stimulates growth hormone release, also promotes slow wave sleep, creating a reinforcing loop between deep sleep and recovery hormones.^[4]

Heat exposure, prolactin, and sleep pressure

Prolactin is a pituitary hormone best known for reproductive signaling, but it also interacts with sleep regulation. Patrick’s interest here is practical: heat exposure can increase prolactin, and prolactin appears to rise during sleep and track with sleep intensity in human physiology research.^[5]

In sauna studies, hormonal responses can be substantial, including increases in prolactin and growth hormone after heat stress, especially with higher heat loads.

Sleep, testosterone, and why timing matters for “patrick sleep”

Testosterone is the primary male androgen, supporting libido, muscle protein synthesis, red blood cell production, and mood. Sleep loss measurably lowers testosterone in men. In a controlled study of healthy young men, one week of sleep restriction reduced daytime testosterone levels compared with well-rested sleep.^[6]

That does not mean a sauna “boosts testosterone” directly. It means sleep quality and sleep depth are upstream levers for normal hormone rhythm. Low testosterone is diagnosed by a clinician using symptoms plus at least two early-morning total testosterone tests, because levels vary day to day and by assay. If results are borderline (or if SHBG is abnormal), clinicians may also assess free testosterone (often alongside SHBG) using reliable methods; guideline cutoffs can vary by organization and lab method, and results typically need confirmation on repeat testing.^[7] If you’re concerned about low T, discuss testing and treatment options with a qualified clinician.

Conditions linked to it

“Patrick sleep” is not a medical treatment, but the sleep stage it targets, slow wave sleep, is clinically relevant. Lower deep sleep and fragmented sleep are linked to worse cognitive outcomes with aging in human research, and sleep is a major focus in dementia risk reduction strategies.^[8]

For men who train hard, deep sleep is also where a lot of recovery signaling happens. Sleep disruption is associated with worse next-day performance, higher perceived effort, and impaired recovery markers in sports and exercise research.^[9]

Heat exposure itself has a safety and health context. Observational data in Finnish men links frequent sauna bathing with lower cardiovascular and all-cause mortality risk, though this does not prove cause and effect.^[10]

Limitations note: Evidence is strongest for warm baths and showers improving sleep onset and efficiency when timed 1 to 2 hours before bed.^[1] Evidence on the exact hormone pathway in humans is more mixed and can vary by heat dose, fitness, hydration, and individual tolerance. Sauna studies often use different protocols, making direct comparisons hard.

Symptoms and signals

If you’re considering the “patrick sleep” approach, look for patterns that suggest your body is struggling to transition into deep sleep or maintain it.

• Trouble falling asleep even when you’re tired
• Light, restless sleep with frequent awakenings
• Early wake-ups and you can’t fall back asleep
• Low morning energy and you need caffeine to feel human
• Workout recovery feels off with heavier soreness than usual
• Lower libido and lower drive alongside poor sleep
• Hot-and-cold swings at night or waking up sweaty
• High stress at bedtime with racing thoughts

Red flags that should change the plan: loud snoring, choking or gasping during sleep, morning headaches, or uncontrolled high blood pressure. These can point to obstructive sleep apnea, a common male sleep disorder that needs medical evaluation before you add stressors like sauna heat.

What to do about it

The goal is simple: use heat to increase sleepiness, then let cooling do the final work. Here’s a practical, clinically cautious way to run a “patrick sleep” experiment for 14 nights.

1. Step 1: Get the basics and risk checks right
   • Screen your sleep. If you snore loudly, have witnessed apneas, or wake unrefreshed, ask your clinician about a sleep study first.
   • Audit alcohol and late caffeine. Both can fragment sleep and blunt deep sleep.
   • If symptoms suggest low testosterone, test it correctly. Discuss testing with your clinician: diagnosis typically uses symptoms plus at least two early-morning total testosterone tests. If results are borderline (or SHBG is abnormal), clinicians may also assess free testosterone (often with SHBG) using reliable methods, with interpretation depending on the lab assay and repeat testing.^[7]
2. Step 2: Choose your heat protocol and time it like “patrick sleep”
   • Sauna option: 20 minutes at 176 degrees Fahrenheit, finishing 1 to 2 hours before bed, then cool down fully before lights out. This matches Rhonda Patrick’s commonly cited heat exposure timing and dose.
   • Bath option: 104 degrees Fahrenheit, submerged from shoulders down as much as possible. Aim for the same 1 to 2 hour pre-bed window, which matches the timing used in sleep research on passive heating.^[1]
   • Cool-down matters: After heat, give yourself enough time to return to a comfortable temperature. Keep the bedroom cool and dark, since nighttime cooling supports sleep physiology.^[2]
   • Hydrate smart: Replace fluids lost through sweating. If you’re prone to leg cramps, talk with your clinician about electrolyte strategy.
3. Step 3: Monitor, adjust, and keep it safe
   • Track outcomes: sleep onset time, number of awakenings, morning energy, and training readiness. A simple 1 to 10 rating each morning is enough.
   • Adjust dose: If you feel wired, shorten the heat exposure, lower the temperature, or move it earlier.
   • Know when to skip heat: fever, dehydration, heavy alcohol use, or illness. If you have cardiovascular disease, fainting history, or uncontrolled blood pressure, ask your clinician before using sauna protocols.^[10]

Myth vs Fact

• Myth: “If heat helps sleep, hotter and longer is better.”
  Fact: Sleep benefits are dose- and timing-dependent. Too much heat too close to bedtime can backfire by keeping core temperature elevated.^[1],[2]
• Myth: “Patrick sleep is a replacement for a cool room.”
  Fact: Cooling still supports the normal nighttime temperature drop. Heat is a pre-bed tool, not the all-night environment.^[2]
• Myth: “A sauna is basically testosterone therapy.”
  Fact: The strongest evidence links sleep loss to lower testosterone in men, and better sleep supports healthier hormone rhythm. Testosterone deficiency is evaluated by a clinician using symptoms plus repeat early-morning testing (and sometimes free testosterone/SHBG), not by heat exposure.^[6],[7]
• Myth: “If I wake up at 3 a.m., I should take a hot shower.”
  Fact: Middle-of-the-night heat can disrupt the cooling signal your body needs. If you wake up sweaty, focus on cooling and hydration the next day.

Bottom line

The “patrick sleep” heat protocol is a simple idea with real physiology behind it: short, deliberate heat exposure 1 to 2 hours before bed, followed by a true cool-down, can make it easier to fall asleep and may support deeper slow wave sleep. For men, that can translate into better recovery and more stable hormone rhythm, as long as you keep the dose reasonable and treat sleep disorders like apnea as the priority.

References

1. Haghayegh S, Khoshnevis S, Smolensky MH, et al. Before-bedtime passive body heating by warm shower or bath to improve sleep: A systematic review and meta-analysis. Sleep medicine reviews. 2019;46:124-135. PMID: 31102877
2. Kräuchi K. The human sleep-wake cycle reconsidered from a thermoregulatory point of view. Physiology & behavior. 2007;90:236-45. PMID: 17049364
3. Van Cauter E, Plat L. Physiology of growth hormone secretion during sleep. The Journal of pediatrics. 1996;128:S32-7. PMID: 8627466
4. Steiger A. Sleep and the hypothalamo-pituitary-adrenocortical system. Sleep medicine reviews. 2002;6:125-38. PMID: 12531148
5. Spiegel K, Leproult R, Van Cauter E. Impact of sleep debt on metabolic and endocrine function. Lancet (London, England). 1999;354:1435-9. PMID: 10543671
6. Leproult R, Van Cauter E. Effect of 1 week of sleep restriction on testosterone levels in young healthy men. JAMA. 2011;305:2173-4. PMID: 21632481
7. Mulhall JP, Trost LW, Brannigan RE, et al. Evaluation and Management of Testosterone Deficiency: AUA Guideline. The Journal of urology. 2018;200:423-432. PMID: 29601923
8. Ju YE, Lucey BP, Holtzman DM. Sleep and Alzheimer disease pathology–a bidirectional relationship. Nature reviews. Neurology. 2014;10:115-9. PMID: 24366271
9. Fullagar HH, Skorski S, Duffield R, et al. Sleep and athletic performance: the effects of sleep loss on exercise performance, and physiological and cognitive responses to exercise. Sports medicine (Auckland, N.Z.). 2015;45:161-86. PMID: 25315456
10. Laukkanen T, Khan H, Zaccardi F, et al. Association between sauna bathing and fatal cardiovascular and all-cause mortality events. JAMA internal medicine. 2015;175:542-8. PMID: 25705824