Heat Stress
Episodes
Dr. Andy Galpin & Dr. Rhonda Patrick discuss nutrition, supplement, and recovery strategies for improving exercise performance.
In this clip, Dr. Rhonda Patrick discusses sauna benefits, including exercise effects, mood improvement, immune support, and potential depression treatment.
This is my keynote presentation from the 2024 CrossFit Health Summit where I explored how vigorous exercise and heat stress contribute to longevity.
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Exercise Supplements Nutrition Sleep Performance Omega-3 Vitamin E Heat Stress Cold Stress Iron ProteinDr. Andy Galpin & Dr. Rhonda Patrick discuss nutrition, supplement, and recovery strategies for improving exercise performance.
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In this clip, Dr. Rhonda Patrick discusses sauna benefits, including exercise effects, mood improvement, immune support, and potential depression treatment.
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This is my keynote presentation from the 2024 CrossFit Health Summit where I explored how vigorous exercise and heat stress contribute to longevity.
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Heat therapy (saunas, exercise, hot baths) can enhance slow-wave sleep. This video explores exercise and heat's joint role in sleep regulation.
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In this clip, Dr. Stuart Phillips discusses how heat stress promotes muscle health and reduces muscle loss.
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MedCram co-founder Kyle Allred discusses sauna's exercise mimetic, anti-inflammatory, mood-elevating, and detoxifying properties in this episode.
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In this clip, Dr. Ashley Mason describes the differences between sauna use and whole-body hyperthermia; how the latter may be useful in treating people who have depression; and how a new trial will investigate its use.
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Rhonda Vitamin D Sleep Vitamin C Inflammation Fasting Pregnancy Coffee Vaccine Heat Stress Dementia Resveratrol Calcium Sulforaphane Sauna Time-Restricted Eating Protein COVID-19Dr. Rhonda Patrick answers audience questions on various health, nutrition, and science topics in this Q&A session.
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In this clip, Dr. Rhonda Patrick discusses how heat can be used to increase muscle strength and counteract muscle wasting.
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Rhonda Brain Vitamin C Immune System Magnesium Heat Stress Muscle Cold Stress Vitamin K Zinc Sulforaphane Sauna Vegetarian COVID-19 Cocoa LactateDr. Rhonda Patrick answers audience questions on various health, nutrition, and science topics in this Q&A session.
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Sauna use boosts lifespan and overall health supported by compelling data from observational, interventional, and mechanistic studies.
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Dr. Charles Raison discusses his belief that ancient practices are more likely than modern pharmacology to encourage resilience and stave off depression.
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Dr. Charles Raison explains how agents that interact with the immune system may play a subtle and complex role in depression.
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Whole-body hyperthermia as a treatment for depression: sauna, hot yoga and exercise | Charles RaisonDr. Charles Raison describes how whole-body hyperthermia has the potential for real-world clinical efficacy as a tool in the fight against major depression.
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Dr. Charles Raison explains the relationship between thermoregulatory dysfunction and how periodic exposure to high heat may aid with treating depression and schizophrenia.
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Dr. Charles Raison highlights how ancient practices such as heat exposure, long-distance running and fasting may promote well-being in the modern world.
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Dr. Jari Laukkanen discusses the benefits and risks associated with cold water immersion following sauna use.
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Dr. Matthew Walker describes the role of temperature in augmenting sleep.
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Epigenetics Vitamin D Nutrition Exercise Aging Metabolism Sleep Diabetes Telomeres DNA Damage Stem Cells Stress Melatonin Vitamin E Genetics 23andMe Heat Stress Autophagy Autism Folate Sauna AntioxidantOur genes influence the way we absorb and metabolize micronutrients. Nutrigenomics looks at the influence genetic variation has over micronutrient absorption/metabolism and the biological consequences of this dynamic relationship.
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Heat Stress Alzheimer's Aging Heart Disease Podcast Video Blood Pressure Protein Aerobic CardiovascularDr. Jari Laukkanen discusses the role of heat stress in the prevention of cardiovascular & Alzheimer’s disease.
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Dr. Gordon Lithgow discusses the roles of protein aggregation, iron overload, and others in the aging process.
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Sulforaphane Nutrition Brain Diet Nootropics Inflammation Heat Stress Autism Isothiocyanates NRF2 Moringa SupplementsDr. Jed W. Fahey discusses the health benefits of isothiocyanates, including sulforaphane and moringa.
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Heat Stress Exercise Brain Aging Performance Heart Disease Depression Memory Anxiety Cold Stress MortalityThis episode is a presentation Dr. Rhonda Patrick delivered at the Biohacker Summit in Helsinki, Finland in 2016.
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In this video, Dr. Rhonda Patrick summarizes a recent study that found that frequency of sauna use was associated with increased decreased risk of death. Using the sauna 2-3 times per week was associated with 24% lower all-cause mortality and 4-7 times per week decreased all-cause mortality by 40%.
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Sauna Exercise Brain Aging Hormones Performance Insulin Resistance Depression Stress Heat Stress MuscleDr. Rhonda Patrick discusses how conditioning the body to heat stress through sauna use, called "hyperthermic conditioning" may cause adaptations that increase athletic endurance (by increasing plasma volume and blood flow to heart and muscles) and potentially even muscle mass.
Topic Pages
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Depression
Depression – a neuropsychiatric disorder affecting 322 million people worldwide – is characterized by negative mood and metabolic, hormonal, and immune disturbances.
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Sauna
Sauna use exposes the body to extreme heat and, in turn, induces protective responses that improve health and may increase healthspan.
News & Publications
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Regular infrared sauna use increases blood vessel density in aged muscles by 33%, though muscle size, strength, and protein synthesis remain unchanged. pubmed.ncbi.nlm.nih.gov
Scientists have speculated that regular heat exposure, such as that experienced in a sauna, might help aging muscles adapt in ways that preserve strength and mass. A recent study found that older adults who engaged in infrared sauna sessions regularly experienced a 33% increase in the number of small blood vessels surrounding their muscle fibers.
Researchers asked 14 healthy older adults (65 to 85 years old) to sit in an infrared sauna (60°C, 140°F) for 45 minutes, three times weekly, for eight weeks. They collected muscle biopsies before and after the heat exposure to measure capillarization—the number of capillaries around each muscle fiber—as well as muscle size. They also tracked muscle protein synthesis using amino acid infusions and ultrasound imaging to assess how well blood flowed through muscle tissue after eating. Finally, they measured leg strength using a one-repetition maximum test.
After eight weeks of heat therapy, participants had 31% to 33% more capillaries surrounding both type I and type II muscle fibers. However, muscle blood flow, protein synthesis rates, leg strength, and muscle size did not improve. Body weight, body composition, and walking speed also stayed the same. The only physical performance measure that improved was handgrip strength, which increased slightly. Interestingly, systolic blood pressure dropped by 2%, while diastolic pressure and resting heart rate were unchanged.
These findings suggest that passive heat treatment can increase blood vessel density in older muscle tissue, but this change alone doesn’t improve nutrient delivery, muscle building, or strength. Heat exposure might support muscle health in other ways, but it doesn’t appear to be a replacement for resistance or aerobic exercise. Learn more about the benefits of heat exposure in Aliquot #96: Thermal Stress, Part I: The Science Behind Heat Stress and its Positive Effects on Health.
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Post-exercise hot tubs and saunas show minimal, inconsistent benefits in exercise performance enhancement, despite potential physiological effects. bmcsportsscimedrehabil.biomedcentral.com
Training in hot conditions can drive marked improvements in endurance by triggering cardiovascular and thermoregulatory adaptations. However, access to heat training chambers is limited, and the physical demands of exercising in high temperatures can be risky or impractical. A recent study found that sitting in a sauna or soaking in hot water after exercise—a practice known as “passive heat acclimation"—might offer some of the same benefits as working out in the heat, but the evidence was weak and inconsistent.
Researchers reviewed 10 studies involving nearly 200 healthy adults, comparing those who used post-exercise heat exposure via sauna or hot water immersion to those who did not. All participants completed similar exercise training programs, and the researchers analyzed outcomes related to performance in hot or neutral conditions, aerobic capacity, heart rate, body temperature, sweat response, and perceived exertion.
The analysis revealed little to no improvement in performance for those using passive heat acclimation, identifying only a 4% difference between groups—an effect that was statistically weak and inconsistent across individuals. Heat exposure slightly improved maximum oxygen uptake, sweat rate, and thermal discomfort ratings. However, the overall certainty of the evidence was low to very low, due to small study sizes and inconsistent reporting.
These findings suggest that while passive heat exposure may exert some physiological effects, its ability to improve exercise performance remains unclear. More rigorous, well-controlled trials are needed before recommending hot tubs or saunas as a reliable substitute for training in the heat. Learn more about heat exposure in this peer-reviewed article by Dr. Rhonda Patrick.
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Warming muscles prior to high-intensity exercise boosts power and performance by 11%, suggests a small study on cyclists. link.springer.com
Study link:
Athletes often warm up before a big race, but does heating your muscles make a difference? An early study found that warming muscles boosts performance by 11% during intense exercise—but at a cost.
Researchers asked four young, healthy adults to perform 20-second high-intensity sprints on an exercise bike under four different muscle temperature conditions: room temperature, after leg immersion in hot water (44°C/111.2°F), and after immersion in cool water (18°C/64.4°F and 12°C/53.6°F). They measured the participants' muscle temperature and analyzed their peak force and power output during each sprint.
They found that increasing muscle temperature using warm water immersion boosted peak force and power 11% more than resting at room temperature. In contrast, cooling the legs in 18°C (64.4°F) and 12°C (53.6°F) water decreased power output 12% and 21% more, respectively. However, higher muscle temperatures also led to quicker fatigue during the sprints. The beneficial effect of temperature was greater at higher pedaling speeds, with a 10% increase in power for every degree (1°C/1.8°F) increase in temperature at the fastest speed.
It’s important to note that this was a small study that was conducted several years ago. However, the findings suggest that warming muscles before high-intensity exercise enhances power and performance, particularly at faster speeds. This benefit comes with a trade-off of earlier fatigue, potentially limiting endurance activity performance. Cooling, on the other hand, may reduce power output but could extend endurance by slowing the onset of fatigue.
Interestingly, research shows that warming the body after exercise—in a sauna, for example—can boost performance. In contrast, cCooling the body after exercise may improve glucose and lipid metabolism, decrease inflammation, improve cognitive performance, and enhance immune function — possibly at the cost of reductions in hypertrophy. Learn more in this episode featuring Dr. Rhonda Patrick.
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Hot water baths before bedtime reduce the risk of hypertension. www.eurekalert.org
Older adults who regularly bathed in hot springs in the evening were less likely to have hypertension, a new study has found. Having hypertension markedly increased the likelihood of having other chronic diseases, however.
Researchers gathered information about the hot spring bathing habits and overall health of more than 10,000 older adults. The participants lived near Beppu, Japan, an area known for its many hot springs.
They found that older adults who regularly bathed in hot springs in the evening were approximately 15 percent less likely to have hypertension. Older adults who didn’t frequent the hot springs were roughly 50 percent more likely to have type 2 diabetes, heart arrhythmia, stroke, gout, or abnormal blood lipids.
Evidence suggests that chronic mental stress promotes hypertension. Research has shown that bathing in hot springs improves mental health and reduces stress. Other research has shown that hot water bathing before bedtime promotes faster sleep onset and better sleep quality, which could reduce the risk of developing hypertension.
Exercise, hot baths, and sauna use may have similar effects on promoting sleep and reducing blood pressure. Learn more about the effects of sauna use on hypertension in this clip featuring Dr. Jari Laukkanen.