I recently purchased a new heart rate moniter and it confirmed what I'd suspected for a while; when exercising at anything more than an extremely moderate pace, my heart rate goes above the 85% range of my maximum and stays there. I have considerable drop in the first minute after ceasing exercise, (as much as 45 beats per minute). My question is: am I doing harm by regularly and repeatedly exercising in the "performance zone" of 85%+?
I've actually been able to take my heart rate above what it calculates my maximum heart rate to be.
A few stats for some background:
39 years old, 6'2" 195 lbs. Resting heart rate:42 beats per minute. I do 3 different cardio workouts, 1 is a sprint workout for about 15 minutes, one is a combination run (2-3 miles) bike 10-30 kms and run 1 1/2 to 2 1/2 miles and the third is a long slow distance run of at least 6 miles at 10 minutes per mile.
I find I have to work hard to keep my heart rate below the 85% range even when doing 10 minute miles. In my shorter runs I run at about a 6:40 and am able to run a sub 6 minute mile. I also use weight training and am ramping up the on bike workouts as the weather warms up.
I'm training for bike race season, both road and mountain and duathlons but I'm wondering if I should be emphasizing the "fitness zone" of 65-85% more than the "performance zone" of 85% plus.
While I appreciate all responses, I would actually only like to hear from well qualified persons, I dont mean to be rude, but I can speculate just fine on my own and would like serious answers from people trained, qualified and experienced in high performance training. THanks, no disrespect intended

If you specifically want a detailed answer by a qualifyed pro who would have to take time out of there working day to cater for your exact needs then you'll have to pay them.

Here we answer question in a way that will help everyone that reads them.

so... If your trying to loose fat, then yeah, keep your heart rate slightly lower so that you can run for longer, but if your trying to get fit, then the higher the better. There is nothing better than HIIT for fitness.
Distance running will only shatter your knees and break down your hard earned muscle.

Keep it short (20mins) and your heart rate high.

Also try to forget about these "Zones". they are just made up words like "tonning" to get people in expensive gyms and make them stay there.

Honestly, I don't know about the effects of exceeding 85% consistently. I remember during a cardiac stress test (on a treadmill), they were trying to get my heart to >90% but that was under controlled settings and for just 30 minutes or so.

I would wonder about blood pressure. Maybe monitor your resting BP and contrast that against the readings as you're doing 80-85%. Then I'd probably check it out with a doctor just to be sure.

Firedude,

I am assuming your heart rate is in the 150bpm range but you are shooting for about 135bpm (for 75% of max) range?

When you are calculating your target heart rate are you using the general 220 minus your age calculator that says 39 y.o. man THR = 108-135 bpm

Or are you using a more detailed calculator (I found this one: Target Heart Rate Calculator) that takes into account your physical fitness, and still coming out too high?

Based on your RHR (very low at 42) and the description of your workout, although Father Time may say you are 39 you are probably much healthier than most 30 year olds out there (who HR at 70-75% would be in the 133-142 range) . Your target heart rate, is probably higher than the general calculator would indicate.

If, however, your heart rate is off the charts even for a virile fit dude like yourself at a 10 minute mile, then you should definately see a doctor to make sure everything is kosher.