Over the past few months, having worked on several major running events - I have encountered a great number of people suffering from various conditions - such as Achilles tendonitis, plantar fasciitis and runners knee.
Many of these people were suffering due to mal-alignment of the Tibio-tarsal joint - meaning the ankle joint. Often this mal-alignment is caused by untreated ankle sprains - or sometimes even minor strains/rolls.
For long distance running it is VERY important to have your feet verified by a Sports PT, an osteopath or a chiropractor. Excessive loading on a misaligned joint can provoque all sorts of pains and aches. The stress on the muscles is more than they can take and they respond by getting inflamed.
Once the body understands that the realignment has taken place the muscles will again begin working normally and the pain will subside.
PB from Geneva, Mai 3, 2014