So I have a lifeguard test tomorrow. I can swim a 500 and pass a written exam but there's one thing... I'm AWFUL at treading water. For this test you're not aloud to use your arms, it's just your legs. I've tried pretty much all the techniques. Any tips/pointers to help me to finish this 2 mins? I can tread for about 45 seconds then my legs get extremely tried and I have to use my arms..