To get some perspective for what power means in human terms, we can look at how many watts a typical rider uses on a standard bicycle. Just pedaling along at a typical cruising speed for a non-sporting rider (about 9 mph) takes about 30 watts, about the same energy as normal walking. Go up to 20 mph, and thus rapidly increasing aerodynamic loads, and 220 watts is needed—more than most non-athletes can sustain. Riding up a mild 10 percent grade at just faster than a walking pace takes 150 watts—enough to have most riders breathing and sweating heavily. Tour de France quality racers, though, can put out 400 watts for an hour, and somewhere over 1000 watts on the short sprint to the finish at the end of a race. The 750 watts allowed for e-bikes under US regulations means we can all have the legs and lungs of a professional bicycle racer.