Running Cooling Strategies in Practice: The Science of Core Precooling, Carotid Ice Packs, and In-Race Cooling

Why Is Cooling Down So Important in Running?

The optimal core body temperature for human exercise is 37.5~38.5°C. Once it exceeds 39°C, the following begins:

• Cognitive function declines (slower decision-making)
• Central nervous system fatigue signals increase
• Blood is redistributed to the skin for heat dissipation (stealing blood supply from the legs)
• Pace is forced to drop by 10~20%

Once it exceeds 40°C, you are on the verge of heat stroke. During Taiwan’s May to October marathons (such as Wan Jin Shi, Tian Zhong, Meng Jia, etc.), cases of core body temperature above 39.5°C are common.

The Three Key Timing Windows for Cooling

Timing 1: Pre-cooling Before the Race

Goal: Lower core body temperature by 0.3~0.5°C before the start, delaying the time it takes to reach 39°C

A 2018 Journal of Sports Sciences meta-analysis found that pre-cooling can extend endurance performance in hot environments by 5~12%.

How to do it:

Method	Effect	Best Time
Drink 500ml of slushie	★★★★★	30~60 minutes before the start
Ice vest	★★★★☆	20 minutes before the start
Cold water wipe on carotid artery	★★★☆☆	10 minutes before the start
Cold water bath	★★★★★	1~2 hours before the race

Slushie recipe (homemade):

• 250ml sports drink + 250g ice cubes + 1 packet of energy gel
• Blend into a slushie with a blender
• Drink slowly 30~45 minutes before the start (to avoid stomach discomfort)

Timing 2: Mid-race Cooling

Goal: Cool down once at every 5K aid station, keeping core body temperature stable below 39°C

Carotid Artery Ice Application

The carotid arteries on both sides of the neck are close to the skin, so applying ice can quickly cool the blood flowing to the brain:

• Hold ice for 30 seconds → core body temperature drops by 0.1~0.2°C
• Soak a towel in ice water and wrap it around the neck → continuous cooling
• Hang an ice pack behind the neck → extends the cooling effect

Sponges/Water

Sponges commonly found at international marathon aid stations:

• Wring out water and wipe the back of the neck, temples, and wrists
• Do not wipe on the top of the head (evaporation is too fast, limited effect)
• Do not pour into running shoes (can cause blisters)

Priority of Areas for Pouring Water

1. Top of the head and back of the neck (dense capillaries, close to the carotid artery)
2. Chest and shoulders (large surface area for heat dissipation)
3. Front of the thighs (femoral artery passes through)
4. ❌ Do not pour on the back (soaking the running top causes chafing)

Where to Stuff Ice Cubes

• Back of the neck: Stuff ice cubes into a headband
• Underarms: Wrap a bandage across the chest to hold ice cubes
• Inside gloves: Hold ice cubes (be careful of frostbite)

Timing 3: Rapid Cooling After the Race

Goal: Bring core body temperature back below 38°C within 30 minutes

Procedure:

1. Cold water immersion (15°C): 5~10 minutes
2. Drink 500ml of ice-cold sports drink
3. Rest in a cool, ventilated area
4. Do not drink beer immediately (alcohol dilates blood vessels and actually raises body temperature)

Cooling Strategies for Different Race Distances

5K~10K: Not Much Cooling Needed

Short-distance races end before core body temperature rises significantly, so pre-cooling has limited effect. The key is simply wiping down with cold water 30 minutes before the start.

Half Marathon: Moderate Cooling

• Drink 300~500ml of slushie before the race
• Wipe the neck with cold water at every aid station
• Wear a thin headband soaked in water for cooling

Full Marathon: Systematic Cooling

• 500ml slushie 1 hour before the race
• Cool down at every 5K aid station
• Increase ice cube usage after the middle section (25K)
• Use a cooling headband or cooling towel

Ultramarathon (50K+): Core Body Temperature Management

• Monitor body temperature (ear or oral thermometer)
• Relay cooling stations (prepared by family)
• Reduce pace by 10~15% if necessary

Recommended Cooling Gear

Buff CoolNet UV+

• When wet, can reduce perceived temperature by 5~8°C
• Dual use as headband or neck gaiter
• Price: NT$700~900

Mission Cooling Towel

• Wring out after wetting for instant cooling
• Provides continuous cooling for 2~3 hours
• Price: NT$500~800

Hyperice X Ice Pack

• Rapid post-race cold therapy for knees and ankles
• Temperature controlled to 5~15°C
• Price: NT$15,000+

The Psychological Aspect: Perceived Cooling

A 2017 European Journal of Applied Physiology study found that the sensation of cold ≠ actual cooling, but both have a positive effect on performance.

This means: a cool sensation (mint, menthol) can make you run faster even without actual physical cooling.

Practical tips:

• Chew mint gum
• Spray peppermint essential oil on the neck
• Apply cooling essential oil to the temples

This is a legal “cold illusion” hack.

Real-World International Marathon Case Studies

2019 Tokyo Marathon (30°C High Heat)

Kipchoge used the following in the INEOS 1:59 Challenge:

• Pre-race slushie
• Cold water spray every kilometer
• Pacers surrounding him to reduce wind resistance and provide cooling

2022 Boston Marathon (28°C)

Molly Seidel confirmed using:

• 15 minutes of pre-cooling with an ice vest
• Ice cubes stuffed down the chest at every aid station
• Finished with a core body temperature of 38.7°C (ideal range)

Conclusion

To break personal records in Taiwan’s summer marathons, cooling is more important than GU. A systematic three-stage cooling approach—pre-cooling, mid-race, and post-race—can improve your endurance performance by 5~12%.

Recommendations:

1. Must-do: Pre-race slushie + cold water neck wipe at every aid station
2. Advanced: Ice vest + carotid artery ice application
3. Elite: Core body temperature monitoring + personalized cooling

Don’t let the “heat” become the invisible killer on your path to a PB.

Related Reading

• Core Temperature Regulation in Running: Heat Balance Mechanisms Under Taiwan’s Summer Heat
• Running Strategies in Hot Environments: Heat Dissipation and Pace Adjustment for Taiwan Summer Training
• Running in Taiwan’s Summer Heat: Training Strategies for 33°C Hot Conditions
• Body Temperature Regulation in Running: The Physiological Challenges of Summer Road Racing in Taiwan