Way back in 07 I think it was I saw my first video for the start of the Sharkfest, jumping off the boat, and my first thought was "I have to do that!" I've since done 2 more swims or swim/runs, and still think it's one of the most amazing starts in racing. Safest? Maybe not, as you are jumping into some pretty cold water. It's definitely a shock. And yes, couple years ago at the challenge as I was bobbing back up the girl behind me jumped, and landed on my kidney. That one hurt.

But there is no way to provide a warmup. Swimming in aquatic park (if that's where it is ending) is useless since you've got the whole walk to the pier/boat ride out time. I think it's up to racers to prepare themselves properly for the conditions, including practice swims, regular checkups, heart evals, etc.

Wildflower and Oceanside also allow very little warmup in cold water, but at least it is some, and there's probably ways to expand that. here, there is no way to get around the first jump, other than having the start 5 minutes after the jump (then you're waiting and drifting in cold water). I fear the Alcatraz races may be at risk with the (not unreasonable) push for warmups.