Why Astronauts and F1 Drivers Wear Cooling Vests (And What We Can Learn From Them)

Whether you're running a marathon in July, working a construction job, or competing in a professional sport, one challenge remains the same: keeping your body cool.

When the body's cooling systems begin to fall behind, performance suffers. Heart rate climbs, perceived effort increases, decision making slows, and eventually heat illness becomes a real concern.¹

Some of the world's most demanding professions have turned to an elegant solution: liquid cooling garments. Astronauts rely on them during spacewalks, while Formula 1 drivers often use cooling systems before or during races to help manage extreme heat. Although these systems were designed for very different environments, they all work using the same basic principles of heat transfer.

Let's take a look at how cooling vests work, why they are so effective, and what they teach us about staying cooler in hot conditions.

The Human Body Is Constantly Producing Heat

The human body is surprisingly inefficient. During exercise, only about 20 to 25 percent of the energy your muscles produce is converted into movement. The remaining 75 to 80 percent becomes heat that must be removed to maintain a safe body temperature.²

Your body primarily loses this heat through four mechanisms:

• Evaporation (sweating)

• Convection (moving air carrying heat away)

• Radiation (infrared heat leaving the body)

• Conduction (direct contact with a cooler object)³

Of these, evaporation is by far the most important during exercise in warm weather. In hot and humid conditions, however, sweat cannot evaporate efficiently because the surrounding air is already saturated with moisture. Sweat drips off instead of cooling you, and body temperature begins to rise.⁴

This is where cooling garments become valuable. Rather than depending on sweat evaporation, they remove heat directly from the body.

The Science Behind Cooling Vests

Cooling vests work because heat naturally moves from warmer objects to cooler ones.

Your skin is typically around 32 to 35°C (90 to 95°F), while chilled water circulating through a cooling vest may be only 10 to 20°C (50 to 68°F). This temperature difference creates a heat gradient that continuously pulls heat away from the body through conduction.³

Many advanced cooling systems circulate cold water through narrow tubes sewn throughout the garment. As the water absorbs heat from the skin, it warms slightly before returning to a cooling reservoir or heat exchanger where it is cooled again. The cycle then repeats continuously.

This process provides a controlled and consistent method of removing body heat without requiring sweat to evaporate.

Unlike simply placing an ice pack on one area of the body, circulating liquid cooling spreads heat removal across a much larger surface area, allowing more heat to be removed comfortably over time.⁵

Why Astronauts Depend on Liquid Cooling

Space presents a unique thermal challenge.

Many people assume space is extremely cold, but the bigger problem during a spacewalk is actually getting rid of excess heat.

Since space is essentially a vacuum, there is no air to carry heat away through convection. Sweat also cannot evaporate inside a sealed spacesuit. Without another method of cooling, an astronaut's body heat would quickly accumulate.⁶

To solve this problem, NASA developed the Liquid Cooling and Ventilation Garment (LCVG).

The LCVG is a close fitting suit containing hundreds of feet of small plastic tubing that circulates chilled water around the astronaut's body beneath the spacesuit. The water absorbs metabolic heat before returning to the spacecraft's life support system, where it is cooled and recirculated.⁶

Without this system, astronauts could overheat during physically demanding spacewalks despite the cold environment surrounding them.

It remains one of the most successful examples of wearable thermal management ever developed.

Why Formula 1 Drivers Need Cooling

Formula 1 drivers experience some of the highest sustained heat loads in professional sports.

Cockpit temperatures commonly exceed 50°C (122°F), while drivers are generating enormous metabolic heat under heavy braking, cornering, and acceleration. Fire resistant racing suits, helmets, gloves, and multiple protective layers make it difficult for heat to escape.⁷

During particularly hot races, drivers may lose between 2 and 5 kilograms (4 to 11 pounds) of body mass through sweating alone if hydration is not aggressively maintained.⁸

Even relatively small increases in core temperature can impair reaction time, concentration, and decision making, all of which are critical at speeds approaching 200 mph.⁹

To combat this, Formula 1 has introduced driver cooling technologies that circulate cooled fluid through garments connected to an onboard cooling system. These systems are designed to reduce heat strain while minimizing additional weight and preserving driver mobility.¹⁰

Although cooling technology in Formula 1 continues to evolve, the underlying principle remains identical to NASA's solution: continuously remove heat before it accumulates.

Why Cooling the Torso Works So Well

Most cooling garments focus on the chest, back, and abdomen rather than the arms or legs.

There are several reasons for this.

First, the torso contains many of the body's largest blood vessels. Cooling these regions helps lower the temperature of blood returning to the heart, allowing cooler blood to circulate throughout the body.¹¹

Second, the torso produces a significant portion of the body's metabolic heat during exercise.

Finally, cooling the body's core reduces cardiovascular strain. As body temperature rises, more blood is diverted toward the skin to assist with cooling. This means less blood is available for working muscles. By reducing heat storage, cooling garments help reduce this competition for blood flow.¹²

The result is lower heart rates, reduced perceived exertion, and improved thermal comfort.

Do Cooling Vests Actually Improve Performance?

Research consistently shows that cooling garments reduce physiological strain during exercise in the heat.

Studies have demonstrated benefits including:

• Lower skin temperature¹³

• Reduced cardiovascular strain¹²

• Lower ratings of perceived exertion¹⁴

• Improved thermal comfort¹³

• Improved endurance performance in many hot weather conditions when cooling is applied before or during exercise¹⁵

The greatest benefits are typically seen when exercise occurs in hot environments where sweating alone struggles to maintain body temperature.

Cooling is not a replacement for hydration, however.

Sweating still removes water and electrolytes regardless of how cool you feel. Maintaining adequate fluid and electrolyte intake remains essential for replacing what is lost through sweat and supporting normal physiological function during prolonged activity.¹⁶

What This Means for Everyday Athletes

Most of us are not preparing for a spacewalk or driving an F1 car, but the same physiological principles apply during long runs, cycling sessions, hiking, manual labor, or summer sporting events.

Managing heat before your body becomes overwhelmed can help reduce fatigue and improve comfort.

Strategies include:

• Starting exercise well hydrated

• Replacing electrolytes lost through sweat

• Wearing breathable clothing

• Seeking shade during breaks

• Using cooling towels or cooling garments before or during activity

• Lowering body temperature before exercise when possible

Each of these strategies helps reduce the amount of heat your body must manage.

The Takeaway

Cooling vests work because they enhance one of the most fundamental laws of physics: heat always flows from warmer objects to cooler ones.

By circulating cool liquid next to the skin, these garments remove heat directly from the body through conduction, reducing thermal strain without relying entirely on sweating.

That simple principle has made liquid cooling essential for astronauts working in space and increasingly valuable for Formula 1 drivers competing in some of the hottest and most physically demanding environments on Earth.

While most people will never wear a NASA spacesuit or race an F1 car, the science behind these systems highlights an important lesson. Managing body temperature is one of the most effective ways to preserve performance, reduce fatigue, and stay safer in the heat. Pairing smart cooling strategies with proper hydration and electrolyte replacement gives your body its best chance to perform when temperatures rise.

Sources

1. American College of Sports Medicine. Exercise and Fluid Replacement. Medicine & Science in Sports & Exercise. 2007.

2. Hall JE. Guyton and Hall Textbook of Medical Physiology. 14th Edition. Elsevier. 2021.

3. Kenny GP, Jay O. Thermometry, calorimetry, and mean body temperature during heat stress. Comprehensive Physiology. 2013.

4. Cheung SS. Advanced Environmental Exercise Physiology. Human Kinetics. 2010.

5. Grahn DA, Cao VH, Heller HC. Heat extraction through the palm of one hand improves aerobic exercise endurance in a hot environment. Journal of Applied Physiology. 2005.

6. NASA. Liquid Cooling and Ventilation Garment (LCVG) documentation and Extravehicular Mobility Unit design references.

7. FIA Medical Commission. Heat stress and driver safety guidance.

8. Casa DJ, Armstrong LE, Hillman SK, et al. National Athletic Trainers' Association Position Statement: Fluid Replacement for Athletes. Journal of Athletic Training. 2000.

9. Racinais S, Cocking S, Périard JD. Sports and environmental temperature: From warming up to heating up. Temperature. 2017.

10. FIA. Driver cooling system regulations and technical directives for Formula 1.

11. Crandall CG, González Alonso J. Cardiovascular function in the heat stressed human. Acta Physiologica. 2010.

12. Nybo L, Rasmussen P, Sawka MN. Performance in the heat and strategies for cooling. Scandinavian Journal of Medicine & Science in Sports. 2014.

13. Bongers CCWG, Hopman MTE, Eijsvogels TMH. Cooling interventions for athletes: An overview of effectiveness. Sports Medicine. 2017.

14. Tyler CJ, Sunderland C. Cooling the neck region during exercise improves endurance performance in the heat. British Journal of Sports Medicine. 2011.

15. Stevens CJ, Taylor L, Dascombe BJ. Cooling during exercise and athletic performance. Sports Medicine. 2017.

16. Sawka MN, Burke LM, Eichner ER, et al. American College of Sports Medicine Position Stand: Exercise and Fluid Replacement. Medicine & Science in Sports & Exercise. 2007.