A, athletes do uniform acceleration, and the speed increases evenly, so we know that the displacement that athletes pass in the first half is small, and the displacement that they pass in the second half is large. So, A is wrong.

B, athletes do uniform acceleration, and the speed increases, so the athletes take a long time in the first half and a short time in the second half. So, B is wrong.

C, when studying athletes' technical movements, we can't regard athletes as particles, otherwise we can't distinguish their movements. So, C is wrong.

D, according to the relativity of sports, we can know that the athletes feel the water surface rising during the falling process, so D is correct.

So choose: D.