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How you use heat can enhance how you feel and perform.

Sauna use has gained new popularity, yet its benefits trace back centuries and can be tailored specifically for elite training.

Learning how to incorporate heat exposure can transform your performance and recovery.

So, how can you use the sauna to elevate your athletic potential?

The Main Feature

Leg 1: Physiological Benefits of Heat Exposure – Building Endurance from Within

The body’s response to sauna use is complex and multidimensional, influencing numerous physiological systems essential to athletic performance. When exposed to high heat, body temperature rises, heart rate increases to a level comparable to moderate cardiovascular exercise, and the body begins to sweat heavily, aiming to maintain homeostasis. This leads to a cascade of internal responses, specifically valuable for endurance athletes and anyone engaging in prolonged physical exertion.

1. Heat Shock Proteins (HSPs)
One of the key players in the benefits of sauna is the upregulation of heat shock proteins (HSPs). HSPs protect cells from damage by acting as molecular chaperones, preventing protein degradation and assisting in cellular repair processes. For athletes, this means that post-exercise sauna exposure helps mitigate muscle damage, accelerate tissue repair, and maintain cellular health even under the stress of intensive physical training. Studies show that HSP70, a particular heat shock protein, is significantly upregulated after sauna use, promoting recovery from oxidative stress, enhancing muscular endurance, and safeguarding tissues from injury during high-stress periods.

2. Plasma Volume Expansion and Cardiovascular Efficiency
Endurance sports demand efficient cardiovascular output, and sauna use has shown to be a natural tool for enhancing this. Research indicates that 20-30 minute sauna sessions, 2-3 times per week, can increase blood plasma volume by 10-20%. This adaptation allows athletes to maintain higher heart rates for longer, supporting endurance and allowing for faster nutrient and oxygen delivery to muscles. A seminal study in the Journal of Science and Medicine in Sport revealed that long-distance runners who used sauna protocols regularly improved their running time to exhaustion by an average of 32% after just three weeks of heat exposure. This adaptation, combined with improved thermoregulation, allows for more sustainable performance in both training and competitive settings.

3. Erythropoietin (EPO) Stimulation and Red Blood Cell Production
Heat exposure has also been shown to stimulate erythropoietin (EPO), the hormone responsible for red blood cell production, similar to how altitude training operates. With an increase in red blood cell count, the body can deliver more oxygen to muscles under exertion, supporting sustained high-intensity performance. Studies demonstrate that regular sauna exposure can increase hemoglobin and hematocrit levels, boosting aerobic capacity—an advantage particularly potent for endurance athletes and those in team sports where prolonged effort is required.

T-1: Mental Preparation

Leg 2: The Role of Sauna in Muscle Recovery and Adaptation

Muscle recovery is at the heart of an athlete’s ability to train consistently and perform optimally. In the post-exercise window, saunas can accelerate recovery through mechanisms that promote muscular repair, reduce soreness, and enhance readiness for subsequent sessions.

1. Increased Growth Hormone (GH) Levels
A fascinating benefit of sauna use is its effect on growth hormone levels, which spike in response to heat exposure. In fact, a single 20-minute sauna session at around 80–100°C (176–212°F) has been shown to increase GH levels by up to 200-300%. This hormone plays a key role in muscle repair and protein synthesis, enabling muscles to recover faster and more robustly. For athletes engaging in heavy lifting, sprinting, or plyometric exercises, enhanced GH levels mean a better capacity to repair microtears and adapt to the demands of training more efficiently.

2. Reduction in DOMS (Delayed Onset Muscle Soreness)
Athletes who incorporate saunas into their routines often experience reduced soreness, making it easier to maintain high-frequency training schedules. Heat exposure stimulates blood flow to muscles and joints, accelerating the removal of metabolic waste products like lactic acid. A study from the International Journal of Sports Medicine confirmed that sauna use reduces markers of inflammation and muscle soreness following intensive exercise, allowing athletes to maintain their training load without succumbing to overuse injuries.

3. Enhanced Mitochondrial Biogenesis
Mitochondria are the powerhouse of cells, and boosting mitochondrial function directly impacts an athlete's ability to produce sustained energy. Heat exposure has been shown to stimulate mitochondrial biogenesis (creation of new mitochondria) in skeletal muscle. This adaptation supports prolonged energy output and better muscle endurance, particularly beneficial for athletes in sports requiring high volumes of aerobic activity, such as marathoners, triathletes, and cyclists. Improved mitochondrial efficiency translates to better performance during long periods of exertion and a delayed onset of fatigue.

Part 3: Mental Conditioning and the Resilience Factor

Beyond the physiological benefits, sauna use also plays an integral role in developing mental toughness and resilience—critical components of elite performance.

1. Mental Resilience Through Controlled Discomfort
Sauna exposure trains the mind to withstand discomfort, cultivating a strong mindset in high-stress conditions. This process, sometimes referred to as "psychological hardening," enhances an athlete’s ability to focus and stay calm under pressure. Studies on mental resilience demonstrate that regular heat exposure promotes emotional regulation, helping athletes stay composed during intense competition scenarios where mental endurance is just as important as physical stamina.

2. Enhanced Parasympathetic Activation and Stress Relief
The high heat of a sauna initially stimulates the sympathetic nervous system, but once the session ends, the body shifts into a parasympathetic (rest-and-digest) state, promoting relaxation and recovery. This is particularly important for elite athletes whose training schedules place them in a constant state of alertness and stress. Sauna-induced parasympathetic activation helps regulate cortisol levels and reduces stress, ensuring that athletes can mentally and physically recharge. For world-class athletes with grueling training loads, these relaxation periods can significantly impact recovery quality and overall training consistency.

3. Improved Sleep Quality
Finally, sauna use has been linked to better sleep, an often-overlooked factor in athletic performance. The body's natural drop in temperature after a sauna session can trigger drowsiness and deeper, more restful sleep. Improved sleep quality enhances growth hormone release, cognitive function, and muscle recovery—all critical for athletes who need to perform consistently at peak levels. Athletes like basketball player LeBron James and marathoner Shalane Flanagan have long emphasized the importance of quality sleep in their performance, and for many, regular sauna use contributes to this goal.

So that’s how heat and sauna can improve your fitness.

Coaches Corner

Workout of the Week: 60-Minute HYROX Power Circuit

Designed to mimic the physical demands of a HYROX race, this workout combines endurance, strength, and functional fitness elements, challenging your cardiovascular system while building power, speed, and stamina for each race-style movement.

Total Duration: 60 minutes

Workout Structure:

Minutes 0-15: Warm-Up

• Start with dynamic stretches focusing on major muscle groups (hamstrings, quads, glutes, shoulders).

• Gradually increase your heart rate with 5 minutes of light jogging or rowing.

• Complete 2 rounds of the following to prepare your body for high-intensity intervals:

  • 10 Air Squats

  • 10 Push-Ups

  • 20 Jumping Jacks

• Focus: Prepare your body and central nervous system for explosive, functional movements.

Minutes 15-30: Endurance and Power Blocks

• 3 Rounds (30 seconds work / 30 seconds rest per movement):

  • Ski Erg or Rowing – Keep a consistent high tempo, focusing on strong pulls.

  • Sled Push – Use a moderate load, emphasizing speed over weight.

  • Burpee Broad Jumps – Explosive jumps covering distance; work on minimizing ground contact time.

• Rest for 1 minute between each round.

• Focus: Building cardiovascular and muscular endurance through high-output, functional exercises that emulate HYROX demands.

Minutes 30-45: Strength Intervals

• 3 Rounds (45 seconds work / 15 seconds rest per movement):

  • Farmer's Carry (heavy kettlebells or dumbbells) – Walk with control, focusing on grip strength and core stability.

  • Walking Lunges with Medicine Ball Twist – Hold a ball at chest level, twisting toward your forward leg with each step.

  • Wall Balls – Full-depth squat with a powerful upward throw; aim for a high target.

• Rest for 1 minute between rounds.

• Focus: Build functional strength and control under load, essential for exercises like lunges and carries in HYROX events.

Minutes 45-60: Finisher Circuit – Speed & Mental Toughness

• 2 Rounds:

  • 100m Sprint on Treadmill or Track

  • 10 Kettlebell Swings – Use a challenging weight, focus on explosive hip extension.

  • 15 Box Jumps – Land softly, aiming for height with each jump.

  • 20 Cal Row or Bike – High intensity, giving full effort to maintain a strong pace.

• Rest 1-2 minutes between rounds.

• Focus: Boost muscular endurance and mental grit for the final stages of a HYROX race.

Additional Tips:

• Hydration and Nutrition: Bring water with electrolytes, and if you’re prone to energy dips, consider a small carb snack pre-workout.

• Monitoring: Track your intensity using heart rate or perceived exertion, keeping intervals in Zones 3-4 for endurance and peak power.

• Adjustments: Scale exercises as needed based on your experience with similar race demands and your current fitness level.

Regular training with this HYROX-specific format will help sharpen the diverse skills needed for race day: a combination of strength, endurance, speed, and recovery to bring your performance to the next level.