Pre-Cooling

Pre-cooling can be defined as active cooling to reduce skin and/or deep body temperature prior to exercise. There is good evidence that pre-cooling can enhance performance in events taking between several minutes to an hour. It may delay the attainment of a critical body temperature associated with fatigue, enhance psychophysical response to heat, positively influence pacing and reduce cardiovascular and thermal strain. Cold water immersion (15 minutes), ice vests and liquid conditioning vests (60 minutes) are all effective modalities for pre-cooling and come with both advantages and disadvantages. The selection of a pre-cooling method is dependent upon the event and practical considerations. 

Post-cooling may be defined as active cooling to reduce skin and/or deep body temperature post-exercise and/or between events or training sessions. Between events it may help return body temperature to normal rapidly and delay the attainment of a critical body temperature in subsequent events. It may also be a necessary treatment for exertional heat illness or heat stroke. Post-cooling of previously active muscle may also reduce immunologic and metabolic tissue stress and facilitate recovery between training sessions. The hands and feet are especially good heat exchangers because they have many arteriovenous-anastomoses (AVA’s) that open with hyperthermia. The fastest method of post-cooling is full-body head out immersion in 2^oC water (reduce body temperature on average from 39.5^oC to 37.5^oC in 8 minutes but this may be impractical. Cooling vests and collars (neck and upper chest is a key area) may provide benefits. The maintenance of adequate mean arterial pressure is also a key to rapid cooling.

Protocol:

Pre-Cooling:

• Choose a modality or modalities that suits sport and venue

• Order cooling system early and practise method before implementation

• Apply cooling before and during active warm-up for up to 1 hour

Post-Cooling:

• Whole body immersion in 2C water is optimal

• Target hands, feet upper-chest and neck if cannot use whole-body immersion. Cooling-vests and collars may help and should be worn during active cool-down for up to an hour

• Maintain blood pressure by slowly moving (muscle pump) and adjust posture for head-down feet-up.

Key Learning Points:

• Take the “warm” out of warm-up and use pre-cooling for up to 1 hour to enhance performance and reduce thermal and cardiovascular strain

• To enhance thermal and metabolic recovery use active cooling methods, target high heat loss areas and maintain blood pressure.