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Q: I have a high heart rate (160–170) when I work out, regardless of perceived effort. Will this limit me in longer distances?
A: The short answer is no. Age and athletic history will certainly impact your heart rate, but genetics play a huge part as well. Some people just naturally have higher than usual heart rates, and you might be one of them. As an example, I’ve worked with two 30-year-old Ironman racers with nearly identical athletic histories. Both are sub-nine-hour Ironman finishers, yet one races the marathon at 150 beats per minute while the other races at more than 180!
The more important question—and the longer answer: Is 160–170 the right heart rate for you to be training at? Perceived effort is obviously not the most accurate indicator of exertion level, and what feels easy for a 30–60-minute run might not feel so easy after a 112-mile bike ride. Lactate testing is a great way to determine your optimal training and racing zones, but if you don’t have access to a portable lactate analyzer or lab, you can run an all-out 30-minute effort with your heart rate monitor on. Take the average beats per minute for the last 20 minutes of the run and consider this your threshold rate. Generally speaking, a safe percentage of threshold for an iron-distance event is 80–85 percent, and 87–92 percent for a half.
Greg Close is a third-year professional triathlete and the owner of TriBy3 Performance Coaching in Brooklyn, N.Y.