https://community.usms.org/swimming/f/general/13190/effect-on-water-temperature-on-stroke-length-and-rateWhen I swim in cool water, I usually find myself spinning my arm very quickly, which can't be done for long time in warm water (I will overheat at that kind of speed), And the stroke length is also reduced, resulting in roughly same speed as in warm wateren-USTelligent Community 12