Preparing your feet

The advice below has been provided by GODZone race doctor, Lynne John. Lynne has experienced many Chapters of the event and seen athletes fall foul of the same problems. There may be some helpful insights to help your prepare properly.

At least a month before the race, inspect your feet:

  • If there are any soggy patches in the toe webs, or slight flaking on the soles/sides of the feet, you may have a fungal infection.  Treat it now to prevent it going haywire in the race (clotrimazole cream twice daily to all foot for a month- from GP or pharmacy)
  • Check for horny rough patches (calluses)  around heels/bunion area/sole surface of toes. These dig in and cause painful deep thick blisters in race mode!  In the shower, gently rub with pumice to smooth off gradually over the weeks
  • Go for some 6+ hour hikes over rough hills  in race shoes to check effect on feet (friction areas) and any chaffing caused by socks. If any pressure areas are apparent, cover with stretchy flixomull and overlay with sports strapping tape for further training, and in the race itself….prevention, is better than cure!
  • Consider wearing your sturdy hiking boots/ trekker shoes for the rougher trek sections where running unlikely – extra weight but super protective. Always Check there are no rubbing problems with all shoes chosen. New shoes are a high risk strategy
  • Read the trench foot info below (re drying/sock changing/removing gear when resting/applying various chemicals & antiperspirant)

Trench Foot

This is a medical problem of the feet which develops after prolonged exposure to unsanitary, damp as well as cold conditions. It also is one of the many syndromes which are referred to as “immersion foot syndromes”. The name “trench” is used as a reference to the trench warfare, normally associated with World War I.

This problem with the feet developed in many soldiers while fighting in the First World War. This infection of the feet developed by wet, cold and insanitary conditions in waterlogged trenches which soldiers stood for hours in unable to take off the wet socks or boots. This would gradually cause the feet to go numb as well as the skin would turn blue or red. Left untreated, trench foot  often turned gangrenous and resulted in many amputations. Luckily there have been no amputations at GODZone. During the winter of 1914-1915 there were over 20,000 soldiers in the British Army treated for this condition. With this condition, the infected feet become numb, developing erythrosis which turns the feet red or cyanosis which turns the feet blue because of a terrible vascular supply. The feet could begin to have the stench of decay due to the early phases of necrosis setting in. When the conditions get worse, the feet can also start to swell. Trench foot in advanced stages often has open sores as well as blisters which can lead to fungal infections. This stage is often called topical ulcer or jungle rot. When not treated, trench foot normally results in gangrene, which can eventually lead to foot amputation. If this condition is properly treated, a complete recovery is normal, although it can be marked by short-term severe pain as the feeling in the feet returns.

Trench foot development comes in 3 stages:

  1. Blood vessels are constricted by cold and wetness inside the boot or shoe with too little oxygen getting to the foot cells. The foot becomes cold to the touch, a little swollen, discolored slightly, numb, as well as a little tender to the touch. If the foot is re-warmed at this stage, the damaged tissue normally appears red and feels sensitive. This discomfort can last from days to only hours
  2. Foot cells become damaged by the lack of good circulation. When the blood vessels open up, the tissue swells with excess fluid. Individuals complain of pain which is tingling that never goes away. There is more swelling. Upon re-warming, blisters form and then ulcers where the blisters fall off revealing tissue which is dead underneath. In some severe cases, gangrene will result. Suffering can last from 2 to 6 weeks
  3. May last for weeks or months. Swelling subsides and the foot starts to look normal again. During this stage, the individual can complain of increased sweating of the foot, increase cold sensitivity, as well as varying degrees of itching, pain as well as creeping, tingling, prickly feeling

Trench foot Symptoms

Tingling/itching/burning/painful/ prickly/heavy sensation. Swelling. Cold and blotchy skin. Numbness. Foot appears cyanotic (grey). Or, foot may be dry, red and very painful after warming. Fissures as well as maceration (sogginess) of the skin is common as well as blisters. Skin & tissue (heel, toes, and entire foot) may die and fall off.

Trench foot Treatment

Prevention is the key in treating this condition. Limiting exposure to cold is very important in stopping and treating the trench foot. It is vital to maintain a dry environment inside the shoe as far as possible, including controlling any excessive perspiration.

When exposed to wet and cold condition, the feet when possible should be air-dried and elevated and there should be an exchange of wet socks and shoes for dry ones so that trench foot does not begin to develop.

The treatment for this condition is very close to the treatment for frostbite. The following steps should be taken:

  • Clean and dry thoroughly the feet
  • Avoid synthetic type materials such as vinyl or rubber
  • Wear cloth or leather which can absorb moisture. ‘Wicking’ socks are good
  • Use dry, clean socks daily – or more often during race (every transition?)
  • Use baby powder or talc to keep moisture away (some products like odour eaters are super-absorbent)
  • Affected area should be treated by applying warm packs or soaking in warm water for about 5 minutes
  • While resting or sleeping, do not wear socks
  • Put changes of dry shoes/boots into transition boxes

If the feet have any wounds, they will become very prone to infection. The feet should be checked daily for worsening of symptoms or signs of infections – show race medics if worried.

Drying agents are helpful to control moisture (thus reducing bacterial and fungal overgrowth). Aluminum chloride is the anti-perspirant agent most commonly used in the tropics. Formalin is used as well in other prescription medications. Add the talc too. Applying of betadine (iodine in alcohol) also dries the skin. Apply race lube frequently from race-start to ‘waterproof’ the skin (Gurney Goo and anti-chaffe has tea-tree oil with antibacterial properties).

Pitted Keratolysis

This condition is similar to trench foot. Athletes (especially runners) can also develop a bacterial (Corynebacteria or Micrococcus)  infection of the foot, termed pitted keratolysis, that sports clinicians often misdiagnose, believing it to be a fungal infection. In one study, 14% of competitive athletes had pitted keratolysis. Occlusive footwear coupled with sweating promote the growth of the organism. It appears as discrete, small, crater-like pits on the soles and sides of the toes; a foul odour often occurs. Treatment includes  antibiotic liquids applied to the skin (clindamycin and erythromycin – only from the doctor). However, you can buy from the pharmacy or some supermarkets, topical benzoyl peroxide – usually an ‘acne’ treating cream – (Crystaderm 1%, or eg Panoxyl 2-5%) This not only kills the microorganisms, but also makes the skin dry and inhospitable for bacteria. No athlete should wear cotton socks; these promote bacterial growth by keeping the microenvironment of the foot warm and moist. Synthetic socks, however, wick away the moisture and keep the feet dry and cool.

Potassium Permanganate

Potassium permanganate is an oxidising agent with disinfectant, deodorising and astringent properties. Its chemical formula is KMnO4 and it is sometimes called by its common name Condy’s crystals. Crystals and tablets are available in pharmacies and garden shops. In its raw state potassium permanganate is an odourless dark purple or almost black crystal or granular powder. The main form of use is a potassium permanganate solution that is made by dissolving crystals or powder in water. There is also a more convenient 400mg tablet form of potassium permanganate available to prepare topical solutions.

Potassium permanganate is used in the following dermatological conditions:

  • Infected eczema and blistering skin conditions
  • Wound cleansing, especially weeping ulcers or abscesses
  • Fungal infections such as athlete’s foot

Potassium permanganate baths are effective for the treatment of infected eczema when there are blisters, pus and/or oozing. A potassium permanganate concentration of 1:10000 should be used (pink colour). If using 400mg tablets add one to each 4L of water. The tablets should be dissolved in hot water before pouring into the bath. Twice daily baths for two days help to dry out the weeping sores and soothe the eczema.

A potassium permanganate solution of 1 in 1000 may be used as wet soaks to blistering wounds such as ulcers and abscesses. Strips of cotton or gauze should be soaked in the solution and wrapped around the affected area for 20-30 minutes. The astringent action of potassium permanganate helps to dry out the blister and prepare the wound for other treatment. A 1% solution is used to treat fungal infections such as athlete’s foot.


Potassium permanganate crystals and concentrated solutions are caustic and can burn the skin. Even fairly dilute solutions can irritate skin and repeated use may cause burns. If redness or irritation continues, notify your doctor. When preparing solutions make sure that the crystals or tablets are fully dissolved in water before using. Potassium permanganate soaks are not suitable for dry skin conditions. Note that potassium permanganate may leave a brown stain on skin and nails as well as the bath or vessel holding the solution.

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