has been studying questions like this for more than 20 years, in between running 58 marathons (with a 2:37 PB) and ultra-marathons. He is also a doctor of public health and a professor of exercise science at Appalachian State University in the USA. I

time looking after the nails than lose valuable training time."Here are the most common ailments:Blackish-red and bruised nailsDiagnosis: Subungual hematomaA badge of honour for ultra-runners, black toenails are caused by blood pooling beneath the nail

Guy Meadows of the London  Sleep School (thesleepschool.org). The sleep-disorder specialist and ultra marathoner has worked extensively with distance runners. “They often end up absolutely physically exhausted, but mentally wide awake,” he explains

and transfer their un-tapped glycogen reserves to working muscles – once it’s inside a muscle cell, it stays there until it’s metabolised. "This is why many marathon runners prefer courses with periodic elevation changes, which allow glycogen reserves

the process, the better you'll deal with it over time." Ultra-marathon runner Andy Jones-Wilkins sees his acceptance of pain as a competitive advantage. "The person who knows the suffering is coming, who expects and embraces it, will do better than someone

after each run - 10 minutes each; stretching - vital ultra-sound with freeze gel - seems to help relax the area. It enabled me to carry on training for the Flora London Marathon. See full threadCheck your heel tab isn't too highSam Bean - I am currently