My heart rate during an ironman marathon is usually low to mid 140s, unless it's in Hawaii where the climatic conditions can make it higher. Transcript: "So by the time I get to the marathon of an ironman, my heart rate is actually quite low, would be in the low to mid one '40s, which for me is quite low, simply because there is exhaustion from the rest of the disciplines. And of course, there is excitement, and you push, and it's a race, and all that. But unless it's Hawaii where the heart rate does climb higher because of the climatic conditions, I am mid to low one '40s."