Now and again, I hit the swimming pool. It’s a good way to exercise, but also to relax after a long day in front of my PC. I can do quite a few laps in my front crawl, but only because I don’t use my legs much. I kick steadily to ensure that my legs stay lifted and don’t slow me down. I don’t use my legs much for forward propulsion. An instructor once explained to me that legs can definitely help with propulsion in the front crawl, but only at the cost of much higher energy consumption.