Triathlon - How long to warm up for a Sprint?

I've heard mixed messages, how long do you need to warm up for the swim before a sprint tri (500-750m - pool swim)? The last two sprints I did I had leg cramps during both of them. I think I have decent speed, but near the end my calves start to lock up, and I'm wondering if this is from not warming up enough. My concern is that I'll wear myself out on the warmup and not have as much left for the actual event. I've heard of doing warmups for a sprint for as long as an hour and as little as 20 minutes. What does experince say?

None? :lol:

If it's a swim-bike-run sprint, i usually don't warm up, just some light stretching. I figure the swim gets the blood going enough for the bike and run (i just go easy and spin for the first mile or so on the bike). If anything, i'll make sure to stretch my calves since they have a tendancy to crap at the beginning of the run (which forces me to stop for afew minutes to stretch).

If it's a reverse triathlon (run-bike-swim), then i warm up with a walk/jog. Running 3 miles on cold legs makes for unfun times after the event... :(

On a swim-bike-run sprint tri I like to do lots of good stretching and maybe some calisthenics. If the event allows for some open water swimming I may swim but just to mainly get wet and loosen the suit up.

I stretch & do some jumping. Other than that, the swim is the warm-up.

Maybe the calf cramps are dehydration or nutrition related? Do you get them in training too??

I agree with edbikebabe.... some stretching, then the swim is the warmup.