Just curious to know if anyone can confirm what I was told today. We were at the community pool today trying to beat the heat and some friends and I decided to swim some laps and then tread water. We were talking amongst ourselves trying to figure out how much exercise treading water actual was when the life guard piped up and said that treading water for 45 minutes was the equivilent of running one mile. Can anyone comment on this? I am just curious how one figures something like this out. Thanks!