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Speed Intervals & HR Monitor(6 posts)

Speed Intervals & HR Monitorbisiklet
May 20, 2002 8:22 AM
How do you guys do speed intervals with a HR monitor? For example I do a 5 minute interval with 56x15 with 90+ rpm cadence. but i can see my HR goes up more than 85 percent after 2 or 3 minutes. So that means I can only do a speed interval for 2 or 3 minutes with more than 85 percent of HR. That doesnt sound right, does it? It should be something else measures the intensity of speed intervals.
lag timeDougSloan
May 20, 2002 8:26 AM
Your heart rate lags behind output, and your monitor lags behind heart rate. You are doing more work than you think.

If at the end of the interval where your heart rate is in the goal zone you are going, let's say, 28 mph, and you have sustained that speed the entire interval, you did the same work the whole time. Isn't that the goal?

If you went only by heart rate, you'd have to start out sprinting and then slow to a crawl by the end to keep rate constant. I don't think anyone recommends that.

well see the thing isbisiklet
May 20, 2002 8:31 AM
I cant see how i do because I have a very weird job that never allows me ride outside. I only ride inside.. but you are right.. only a HR monitor should not be something to determine everything.
May 20, 2002 8:35 AM
I'd recommend a device that shows you actual output in watts; they cheapest form for indoors is a trainer with a wattage display. Performance sells one.

I use one. It is the best way to do intervals, in my opinion. You can perfectly control the work you are doing by reading the watt display. You'll be really surprised to see how easy it is to make 400 watts at the beginning of an interval compared to the end, and how useless heart rate is after using a power display.

May 20, 2002 8:38 AM
well thanks Doug. Yea i saw that. I actually was thinking about buying it. I think i am going to go for that. I have a performance trainer so it would be a little cheaper to upgrade I think. Thanks man. You are good.
second vote for power meterDuane Gran
May 20, 2002 9:58 AM
I routinely use a power meter (Polar S710) in my training and swear by it. As Doug pointed out, HR is a poor benchmark for short efforts. Even on longer efforts you experience cardiac drift.

Based on conversations with others who use power meters, the devices are best suited for training your body at your anaerobic threshold. Heart rate is best for low to medium intensitites or as a guide to know when you are about to blow up at high intensity.