Last week I was in Santa Fe enjoying a soak in a hot spring then alternating with a jump into icy cold water. Our friends were questioning the health benefits of both, and the sanity of the latter, and it got us talking shock proteins.
In the quest for better health, sharper focus, faster recovery, and longer life, consider temperature stress as a simple, yet powerful therapy. Whether you’re soaking in a hot bath or plunging into an icy stream, your body responds by producing specialized molecules known as shock proteins. These include heat shock proteins (HSPs) and cold shock proteins (CSPs), your body’s internal repair and protection squads.
While they operate in different ways, both are part of your body’s hormetic response – beneficial stress that makes you stronger.
What Are Heat Shock Proteins?
Heat shock proteins are produced when your core body temperature rises above approximately 102°F. You’ll trigger them during activities like sauna use, hot baths, vigorous exercise, or even fever. Their main job is to protect and repair your cells. They help other proteins fold correctly, prevent clumping, and escort damaged proteins to be broken down and recycled. In this way, HSPs help reduce inflammation, support mitochondrial health, and keep your tissues working smoothly.
The most studied types are HSP70 and HSP90. These play crucial roles in muscle recovery, immune function, and cellular stress management. HSPs also help regulate autophagy, which is your body’s process of cleaning out damaged cells and is linked to longevity.
What Are Cold Shock Proteins?
Cold shock proteins, on the other hand, are released when your core temperature drops, typically below 89°F to 95°F. You can trigger them through cold plunges, cryotherapy, winter swimming, or even cold showers. The two best-known cold shock proteins are RBM3 and CIRP.
RBM3 is especially important for brain health. It has been shown to protect neurons, preserve synapses, and may slow the progression of neurodegenerative diseases like Alzheimer’s. CIRP helps regulate inflammation and stabilize RNA, ensuring your cells can keep functioning under cold stress.
Why Shock Proteins Matter
Both HSPs and CSPs play powerful roles in health and they don’t overlap much. Heat shock proteins are more involved in repair, particularly after physical or metabolic stress. Cold shock proteins focus more on protection, especially of the brain and nervous system. Used intentionally, both can support immunity, lower inflammation, improve metabolism, and potentially extend healthspan.
Heat Shock Proteins (HSPs):
- Support muscle and tissue recovery after workouts
- Help cells survive inflammation and oxidative stress
- Boost mitochondrial function (your energy factories)
- Encourage autophagy (cellular cleanup)
- Assist in immune modulation, especially during infections or chronic stress
Cold Shock Proteins (CSPs):
- Preserve brain function and may delay cognitive decline
- Help reduce systemic inflammation
- Stabilize hormones like norepinephrine and dopamine
- Stimulate brown fat activity, which increases calorie burning and metabolic flexibility
- May improve mood, mental focus, and sleep
When to Use Heat or Cold?
Knowing when to reach for heat or cold can make a big difference. If you’re focused on repair, detoxification, or muscle recovery, heat is the better choice. If you want to stimulate the nervous system, improve metabolic resilience, or protect the brain, cold is your go-to.
Use heat therapy when you’re sore from exercise, dealing with chronic inflammation, want to support immune function or looking for a longevity and detox boost. Use cold therapy when you’re mentally or emotionally drained, want to reduce inflammation or improve mood, trying to increase brown fat and metabolic health or need cognitive clarity or a nervous system reset
How to Activate Shock Proteins
To boost heat shock proteins:
- Sauna: Aim for 15–30 minutes at 175–200°F (traditional dry sauna), ideally 3–5 times per week
- Hot baths or hot tubs: Use water between 104–108°F for 15-20 minutes
- Exercise: Especially high-intensity interval training (HIIT) or long-duration cardio
To stimulate cold shock proteins:
- Cold plunges or ice baths: Use water around 50–59°F for 2–5 minutes.
- Cold showers: Start with 30 seconds and build up to 2–3 minutes.
Which Is Better? Contrast Therapy to the Rescue
There’s no need to pick sides. Both heat and cold shock proteins offer unique advantages, and alternating them can create a powerful adaptation response. For example, athletes often use contrast therapy, that is alternating hot and cold, to speed up recovery. Similarly, longevity protocols may include daily saunas combined with cold plunges to support both cellular repair and nervous system balance. The benefits vary depending on your goals but generally include improved recovery, nervous system regulation, inflammation control, and metabolic adaptation.
One of the most valuable effects of contrast therapy is on the autonomic nervous system. Heat exposure tends to activate the parasympathetic response, promoting relaxation, while cold exposure initially stimulates the sympathetic nervous system, increasing alertness and focus. Alternating between the two helps improve autonomic flexibility, making your body more resilient to stress. This can be particularly helpful for reducing symptoms of anxiety, burnout, and poor sleep.
From a circulatory standpoint, heat causes vasodilation, which opens up blood vessels, while cold causes vasoconstriction, narrowing them. Switching between heat and cold creates a kind of “vascular workout,” improving blood flow, flushing metabolic waste, and reducing inflammation. This mechanism is especially useful for people with sore muscles, joint pain, or poor circulation.
In the realm of athletic recovery, contrast therapy also plays a supportive role. Heat helps muscles relax and activates heat shock proteins (HSPs), which support cellular repair. Cold exposure, particularly cold water immersion, reduces acute inflammation and muscle soreness. However, for those focused on muscle growth, it’s best to wait 4–6 hours after a strength training session before doing cold therapy, as immediate cold can potentially blunt muscle growth signals. That said, on rest days or for general recovery, cold after heat is excellent.
A Shock Protein Regimen
For practical use, many people follow a simple sauna and cold plunge routine. For example, you could spend 15–20 minutes in a sauna or hot tub, followed by a 3-5 minute cold plunge or cold shower. That alone would be great, or after resting briefly, you could repeat this cycle 2–3 times. To finish, end with cold if you want a sense of alertness and inflammation control, or end with heat if you’re trying to wind down for sleep.
Your body was built to adapt to the elements. When used intentionally, heat and cold stress don’t break you, they build you. Shock proteins are the hidden players behind this adaptation, supporting your health in profound ways.
Author
Scott Rollins, MD, is Board Certified with the American Board of Family Practice and the American Board of Anti-Aging and Regenerative Medicine. He specializes in bioidentical hormone replacement for men and women, thyroid and adrenal disorders, fibromyalgia and other complex medical conditions. He is founder and medical director of the Integrative Medicine Center of Western Colorado (www.imcwc.com) and Bellezza Laser Aesthetics (www.bellezzalaser.com). Call (970) 245-6911 for an appointment or more information.
