Sudden heart rate increase after certain amount of exercise?

Question

I am a runner and usually do elliptical workouts every other day (1000 calorie an hour pace for 1.5 hours). I drink 2 cups (cups as in the cooking measurement, more or less one tall glass worth) of gatorade about 45 mintes before each workout.

Every time I use the elliptical machine I notice my heart rate quickly goes up to 150 beats per minute within the first 6 minutes or so and stays at that rate until 40 minutes. However, after 40 minutes (with no change in pace), my heart rate jumps up to about 160-164 and stays at about this level (climbing a bit but not much as time goes on) until the end of the workout...yet I do not feel dyhydrated.

Is my body short of nutrients (and, if so, what is it most likely missing to help it run efficiently) or what is going on here?

Note: if you answer please do not say something vague like "ok, that means you are exercising too hard" that avoids the problem rather than solving it. Thanks. :-)

BTW, a few comments.
Yes I am a 26 year old training for a marathon and I have been running/training for several years 5K (since high school), and doing distances of 10K and over for the last year, I started doing 20K IE half-marathon-ish distances about 1.3 months ago.
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And, far as the comment about 130BPM, I wonder what age (and shape?) that person reporting that is. I'm not an expert on heart rates but I do know someone my age has a maximum cardio rate somewhere over 160 (not sure exactly how far over, though).
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Some info that might help about my physical shape I'm size 30 waist about 11% body fat not a pro but certainly not new to exercise so I doubt any "newbie to exercise" answers will be appropriate.
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Btw, so far, the cardio-ability test answer seems to be the most relevant.

Also, to answer the question about training for the marathon, yes I do long runs every other workout but don't reliable have a heart rate method for those workouts.
The reason I go on the elliptical is to work my heart and cardio strength without ruining my legs (especially bones) from impact.

Some extra info I snagged from Wikipedia:
"The recovery heart rate is one that is taken several minutes after exercise. It is taken anywhere between 2–10 minutes after exercise. It is taken for 15 seconds, and is multiplied by four in order to calculate beats per minute (bpm). The goal is to not exceed 120 bpm."
So, as I understand it, 120bpm is the goal RECOVERY heart rate AFTER rather than DURING exercise and I am talking about the rate DURING exercise (I am guessing this is where the person who thought anything over 120 was crazy got this idea from).
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The other thing I realized is my maximum heart rate in workouts, by Wikipedia's formulas, seems to be somewhere in the anaerobic zone (which tops out at about 170bpm for my age of 26) after 40 minutes and at the top of the aerobic zone (156bpm as I calculated it) before those 40 minutes.
So is it safe to distance exercise in the anaerobic zone (and how far into the red zone may be safe)?

Answer 1

OK, what is happening is you are reaching your maximum heart rate- did you ever have a stress test for your heart? What they do is exercise you on a treadmill and have you running while they keep increasing the resistance and speed to raise your heart rate and blood pressure. Now there is a formula that the Cardiologists use- and I would suggest that you call your GP or see a cardiologist- what you are experiencing is abnormal and has nothing to do with hydration but the way your heart is performing from the workout.

Answer 2

Why on earth are you doing cardio for an hour and a half? I could see if you were training for something like a marathon, but then you would be running. Your heart rate is jumping because your heart is having to work hard. You should be drinking water before a workout. Skip the gatorade until after. If you are working out that hard then your body needs to replenish its sodium and potassium.

Answer 3

It is probably not what you are eating. You say at 40 minutes it jumps up faster. Did you gradually work up to this like over a 2 months time or was it much sooner than that? If you did the 40 minutes less than over 2 months time you are probably overworking your body. If it is the 2months time get to your Doctor ASAP.

Answer 4

There are a few factors to consider here. Your age, your fitness and how long have you been exerciseing at this level.

What's happening is you're over working your heart. It's okay for 40mins (which is long enough for a good workout). If you keep doing this you may do irreversable damage to your heart muscle.

You may have to pace yourself, cut the amount you are doing.

Answer 5

You want to know the thruth? You are exercising way too much.
Your heart can only take so much abuse, any exercise over 120 means you're working way too hard which is not nessecary at all to get results.Your heart can not recover, you're in for a heart attack, and I am not kidding you. Stop it now.

Answer 6

Your heart is working harder to pump blood throughout your body. The faster you go the harder it pumps, thus incressing your pulse. Maintain a regulated pace and drink water during your run. Try it for a week and see how things go.

Answer 7

160 is way too high.. you really need to go see your Family Doctor and let him or her decide what is best for you.. but definatley dont excersise to the point of your heart rate getting that high.. thats not normal!

Answer 8

You are asking a question were the only way you will get a more concrete answer is to go to you physician and get a professional consultation.