There is a significant difference in speed between an Olympic swimmer and a saltwater crocodile. Under ideal conditions in a pool, an Olympic swimmer like Phelps can reach speeds of up to 6 mph in a short sprint. However, a saltwater crocodile can exceed 18 mph in the ocean. While a human swimmer cannot sustain that speed for long, even over a distance of 500m, the swimmer would average closer to 4 mph. In comparison, a crocodile could cover the same distance much faster.

To illustrate this point, let’s consider the fastest recorded time for a freestyle 200m swim in a pool, which is 1 minute and 42 seconds. At a speed of 18.5 mph, a crocodile could cover 1000m in just 2 minutes and 1 second, and it doesn’t necessarily need to cover the full distance to reach the swimmer. Any small error on the part of the swimmer or even a slight increase in speed by the crocodile would put the swimmer in significant danger.

Therefore, in an experiment where the swimmer and the crocodile are pitted against each other over a 500m distance, the crocodile would likely cover the distance in 1 minute or less, while the Olympic champion swimmer would only manage to cover around 160m in the same time, even if they were able to maintain a constant speed of 6 mph. An average swimmer moving at 2 mph would only cover approximately 54m within the time it took for the crocodile to cover the entire 500m distance.