Nigel has always wanted to fully understand the forces and motions at play in mountain biking. Riding on a trail involves a complex interplay of rider movement, suspension, terrain, braking, pedalling, and more. To simplify the analysis, Nigel started by focusing on a rigid pump track bike, which removed many of the dynamics typically encountered on the trail. He then concentrated on the specific action of pumping a single roller in a straight line, eliminating even more variables. By measuring the rider’s input forces and body position, Nigel was able to piece together a clearer picture of what was happening during a pump—how the rider’s effort was converted into forward motion and what truly made a good pump.