PainCreamRandomized Trial of Mannitol Cream for Pain Relief After a Long Run

The hypothesis for this study is that Mannitol cream will reduce post long run pain more than vehicle cream alone. In this parallel design, 170 runners who usually experience a pain level greater than 5/10 on a numerical rating scale from 0 to 10 where zero is no pain and 10 is the worst pain ever, will be given a cream containing 25% mannitol to apply on one leg and the vehicle cream to apply on the other leg. The cream assignment will be randomized, and the runner, the person supplying the cream and the person inputting the data will be blinded as to which leg received which cream. Pain levels in each leg following the long run will be recorded, via an e-mail questionnaire, or, failing this, by telephone, the day of the run, and each day, for five days following the run. Mean and standard deviations for pain levels will be calculated for each treatment leg, and a repeated measures ANOVA (Analysis Of VAriance) will be done comparing the pain levels in each leg over the six days. Using this information, if the NRS (Numeric rating scale) pain levels differ by more than 1/10 between the two groups, a larger study will be conducted using the information gathered in this study to determine sample size.