Using HR to pace first olympic triathlon

If you haven't been been doing heart rate training and don't know your lactic threshhold numbers, then attempting to race by HR isn't going to work very well.

That being said, I've been HR training for about five years and have had lab testing done to determine my threshhold numbers.  On the bike I use a combination of HR and RPE to manage my pace, while keeping my cadence between 85-95 rpm.  I'll set my lower HR alarm at the low end of zone 3 and the high alarm about halfway into zone 4. 

The bottom line is that I'm trying to go as hard as I can on the bike while still saving something for the run. 

My run is my weakest discipline, so if anything I'd rather overdo it on the bike. 

Once I get to the run I mostly go by RPE, but still keep an eye on my HR.  If my HR drops too low, then I know I can probably push harder (even though it is probably going to hurt).

Mark

I did this for my first two olympics.  I had targeted 150 BPM on the bike and 160 on the run based on simplistic HR calculations and more importantly months and months of RPE calibration.  I was worried about bonking.  When I did the races though I ended up averaging 170 and never had any significant lag periods.

Having just done my first HIM, here's my thinking as a MOPer: Sprints- race on the verge of vomiting (as I read on this forum at one point); Olympics- think about a 3 hour brick rate of exertion then add 10%-20% for race pace; HIM- more complicated (and only I have only one race under my belt) but I will try to increase my long (3 hour) practice brick pace and then plan to maintain that for the 5-6 hour race. 

But I defer to more knowledgeable and experienced posts.

Having just done my first HIM, here's my thinking as a MOPer: Sprints- race on the verge of vomiting (as I read on this forum at one point); Olympics- think about a 3 hour brick rate of exertion then add 10%-20% for race pace; HIM- more complicated (and only I have only one race under my belt) but I will try to increase my long (3 hour) practice brick pace and then plan to maintain that for the 5-6 hour race. 
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Oh, there is no science to that, it's just my way of thinking.  In fact it's backward from the way most of the training plans are written (race pace -X%) but a similar idea.  When I was training for the HIM, I did a lot of 3 hour rides and bricks at a steady pace I thought I could hold for a long time (5-6 hours in the race).  I sort of use that now as a baseline.  With more data points (races) to draw from, I am confident that I could push that pace big time for an OLY race.  For my next HIM I intend to train toward increasing this "base" pace.  This all probably goes in the category of doing a lot of training focused on the length of race you're going to do so you know what to expect from your body.