I have once seen it in Turkey's beaches. Women who had worn it didn't seem comfortable in it and couldn't swim well and were shy. What is the idea of Islam about this cloth?
Islam encourages its followers to maintain a healthy body through athletic activities. However, under Sharia law, Muslims are required to cover the genitals - which is considered an intimate part of the body that can only be seen by friends or relatives / friends of the same sex. If he can not swim well not because of his clothing, but because of the lack of ability to swim. Yet for the sake of exercise alone, not for Olympic Games