Does anyone use a chest strap heart rate monitor during a Ironman race?
Yes for my 70.3 and probably would if I did full distance. Garmin hrm-tri is my go to and use the wahoo tickr every now and then.
Absolutely…it is such a long day that proper pacing based strictly on power (bike) or pace (run) can lead to problems. A rising HR can give you an indication that your planned strategy may not be working out.
If you want accuracy. At distance you need to watch drift etc. Hopefully you wear it training so you will be familiar with how heat, hydration, distance, time etc affect you so you know when to back off or can continue to press.
I’ve done it both ways. I used my wrist-based Garmin in my last 70.3 after testing it through a number of training runs. It worked fine to help me pace the sand portions of my run. (I train and race with power both for the bike and for the run via Stryd, but Stryd doesn’t work on soft sand!). I don’t love wearing heart rate straps during races and now with power and pace data widely available, the need to track and monitor HR in real time in most races is significantly reduced from where it was 15 years ago. I’d argue that pointy-end 70.3 racers probably don’t need to bother with HR data except in special cases, but IM is a different animal, and there can be value in accurate HR drift information provided in real time.
My advice would be that if it doesn’t bother you and you want the HR drift data, wear the chest strap. In any event, whatever you choose to do, make sure you’ve trained that way (with/without strap, with/without data) enough. And then I’d remind everyone that more data during a race isn’t necessarily better.
No HR during racing, in fact I wore an Omega wristwatch at my last Ironman