Predictor variables for a 100-km race time in male ultra-marathoners Based on results from 169 finishers at 100 km run in Biel, we have tried to find out if we can develop a formula based on characteristics of body construction as well as the training of the runners to predict the competition time as accurately as possible. The result can be found under https://pubmed.ncbi.nlm.nih.gov/21319608/