[T]he sport shows that you have a normal pattern, a typical ratio of medley freestyle to best freestyle — they SHOULD BE between 18 and 23% slower at the end of a 400m IM than in a 100m freestyle by itself. Yet Shiwen is not. She does a 58.68s final leg, which is only about 10% off the best 100m freestyle swimmers.... The only way to interpret that is to recognise that the physiology of a fast finish tells us that she must have a significant reserve for that final leg. It says that her first 300m was an extremely conservative effort.
Ye's proportions give her an edge, [Ye's coach Ken] Wood says. At 5 feet 8 and 141 pounds, Ye has better power-to-weight ratio than counterparts in other countries, he said. There are also her hands—which the 6-foot-2 Wood says are as big as his—and her size 10.5 feet, which turbocharge her strokes.