Cooling vests

As someone who doesn't like hot weather, I like the idea of cooling vests. I came across a photo of the Garmin cycling team warming up with cooling vests. Here is another photo. I'm not sure how a cooling vest would work for a runner. You can't really warm up on a stationary bike. Maybe doing 20 minutes of running to warm up, then wearing a cooling vest for the last 5-10 minutes before the