Triathlon race day plans using FTP

Hi. I’m currently in week 8 of the half Ironman distance, and was wondering if there are any resources in terms of planning for the big day? Nothing too technical, just interested in not blowing up in the run because I’ve gone too hard on the bike or ran the first 10km like I’m on fire… Is there a percentage of FTP you should stay under, or keeping your HR under your lactate threshold, or some other secret to holding it together on race day? It’s my first one back after an 8 year layoff so I really want to have a relatively good day!! Thanks :grinning:

BestBikeSplit is awesome, used it to plan out a relay I was the biker for. Lots of variables you can apply like max power for climbs and the total intensity you want to apply. Best part is that you can download a file for most head units that gives you queue for what wattage you should be at if you have a power meter

1 Like

Simplest is to pick a HR that you think you can manage for 5or6or7 hours & then target to average that. Somewhere around your LTHR. And then either route plot to determine which hills might require you to burn some matches or pick an upper lower limit around that average. Nothing wrong with interspersing walks into the run to bring down the HR…

1 Like

Hello @Jules_stevo,
Great to hear that you’re prepping a smart race strategy! Generally speaking, on the bike you want to keep calories coming in (early and often), keep your HR under lactate threshold (or power under LT). If there are a few hills that are steep enough to send you over LTHR, even in your easiest gear, then you just get up them and recover once you’re over the top by pedaling (easy-mod) on the downhill to flush your system instead of coasting. On the run, the same principle applies - keep your HR under LT as best you can and walk through the aid stations to take whatever you need (starting early). Bottom line, remember why you’re out there, what your goals are and remember to check in with yourself every so often to make sure your efforts are in line with those goals.


Thank you. I’ll have to have a look. That sounds like taking my planning to a whole new level!!

Thank you so much! Nutrition is a huge struggle of mine. I have a sensitive stomach and I tend to not get enough in on the bike, so certainly going to try and be better so that the last lap of the run is not hell.
A further question though, how do you find your lactate threshold on the run? My watch has given me figures, but I think that’s based on my age. I have my 5 km run test this week, but the link for the info once you have your results doesn’t seem to work?


If nutrition has always been a struggle, I recommend you put a lot of time into experimenting with different fueling strategies to find what works for you, well before event day. Everything from the pre-race meal to what you take in during the bike ride and run. You’ll want to do this before/during sessions that are at race effort since your body will respond differently at different effort levels.

As for the run link, try this one:

As instructed in the 5k test, you’ll run a 5k at best sustainable effort. Take splits every 1k (you can usually set your heart rate monitor to do this automatically) and then analyze the data afterwards to find your average heart rate for the final 20 minutes (which will be your LTHR) and your threshold pace (RTP) is
determined by adding 15 seconds to the average of your 1 kilometer splits.
Does that make sense?
Let us know if you have any more questions, and best of luck!