Fig. 3

An example of the two common prescription methods for MFW exposure (distance vs. time). On the left, it is apparent that athletes running a high training volume (100 km/week) would require a full 20 km of running in MFW to meet the criteria which would present a possibly dangerous exposure. On the right, however, an athlete running just 10 km/week would find themselves running almost entirely in MFW if asked to run 20 min in this footwear, which might also be dangerous, given their low running exposure initially. Therefore, a mixed method is suggested