I've met physical education teacher in the swimming pool and he told me that swimming will NOT have significant effect for developing my vertical jump.
If we omit weight loss caused by swimming and better core muscles stability, can swimming help in developing leg (vertical jump) specific muscle groups? Or swimming (crawl) is focused on developing exactly contra non-water-sports muscle groups?
No. Vertical jump is an indicator of leg and hip power. Swimming doesn't promote the explosive movements required for a large vertical leap, especially not in the leg.
Swimming can of course develop tremendous leg and hip power, especially for breaststroke, but this does not directly translate into an improved vertical jump because the motion is quite different. The sport, however, requires developing an excellent jump for starting and pushing off the wall. For this reason swimmers train for vertical jumping both in and out of the water, although I doubt many swimmers can beat an average NBA vertical. Phelps can.
