Why is it that swimmers often smash world records by half a second, sometimes even one or two seconds...?

Question

Why is it that swimmers often smash world records by half a second, sometimes even one or two seconds while world records in track and field events are held for much longer and when they are beaten, they are only beaten my a very narrow margin.

Answer 1

It probably has something to do with technique. People have probably improved the way they move their arms and legs in the water to allow them to move more swiftly. Cupping their hands differently, kicking their legs more or less , keeping their head lower to the water when they breath, etc... Whereas track is just running, I can't imagine there is much to change with that. The more streamlined suits they now have dramatically reduces drag as well and that can't hurt.

Answer 2

more advanced suits i reckon, like swimming suits