Running: the problem with blisters

Over the years I have taken part in a number of marathon events. Although I am not prone to blisters (losing toe nails is my problem), a number of my friends are. Below you will find some useful information on hydration and blister prevention/ treatment, written by my husband Clive Lathey MSc Sports Medicine.


Hydration

• Dehydration impairs performance and health.
• Fluid loss during exercise dependent on exercise duration, intensity, temperature and humidity. Body size and fitness levels also affect loss.
• Pale to very pale yellow urine is an indication of good hydration. Dark yellow urine indicates advanced dehydration.
• Always start exercise well hydrated. Continue drinking at regular intervals- ideally every 15mins. The aim is to match intake of fluid with the amount of fluid lost.
• Exercise- more intense or lasting longer than 1 hour- solutions sodium + carbohydrate (Sports drinks), can speed up water absorption and provide additional fuel.

Blisters

Prevention

• Always dry your feet; particularly between toes.
• If you have moist feet, use surgical spirit daily to reduce sweat and toughen feet daily for 2 weeks prior to event.
• Try and wear socks containing natural fibres and turn socks inside out to avoid irritation from thick seams.
• Make sure shoes fit correctly. There should be a gap of approximately 1.5cm between the big toe and the end of shoe.
• Use plasters over areas prone to friction, such as: heel, big toe and little toe.

Treatment

• Cover blisters with plaster or blister protector.
• Do not burst blisters. This can lead to infection and, what's more, the fluid inside a blister aids healing.
• If a blister bursts, clean it with warm salty water. Apply sterile antiseptic dressing and keep the affected area dry as possible until it has healed.
• Black toenails usually resolve. The nail may fall off and discolouration can last 12 months.
• If a blister is very large and painful, seek professional medical advice.