Check your manual for sure, but there's absolutely no problem with the polar straps in the water. I've worn my garmin strap in the swim and have not had any issues. I put the watch on my tri bars and hit the timer on the way out of T1, once i'm on my bike, hitting my stride and in a safe place, I put it on my wrist. You have to be pretty confident to do this because it would really suck to drop it. The safest thing to do is to put it on in T1.
When's your race again? I forgot. It's the Oliver HIM right?
How exciting!!!
Living life like there's no tomorrow.
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2007 Look Dura Ace
2010 Custom Tonic cross with discs, SRAM
2012 Moots YBB 2 x 10 Shimano XTR
2014 Soma B-Side SS