I've started doing BFL this week with 20 minutes on the elliptical for my cardio, and I'm having kind of a hard time determining the proper intensity levels and how they relate to heart rate. When I just picked what was comfortable, I started out at about 45 RPMs for my level 5, going up to 78-80 at my level 10. This seems like the right degree of workout difficulty to me -- I'm sweating and breathing hard, but can speak in short sentences (except at level 10, when I'm sprinting as hard as I can).

However, my heart rate, as measured by the elliptical's sensors, is *very* high -- 135-140 within 30 seconds of stepping on it, even though I don't really feel like I'm working hard at that level. Levels 6 through 9 range from 170-190, bumping 200 at level 10. I know I should feel like I'm about to stroke out at that rate, but I feel fine -- I'm not faint or dizzy, and I could probably do an extra level 6-9 if I wanted.

My fiance saw the heart rate number and got kind of freaked out, and he wanted me to try and step back a bit. For Friday's cardio, I tried to do just that, so I just did 20 easy minutes to try and figure out where my heart rate needed to be. I was at a level 2 setting on the machine, no more than 50 RPMs, and wasn't even breathing hard or sweating. I actually carried on quite a long conversation about the war, in fact. I could have gone on like that for another hour, and actually did 10 extra minutes just because I didn't feel like I'd actually done any work. The whole time, my heart rate was 170-180 . By what I've read, that should be very close to my absolute max rate, but it felt like a leisurely stroll. I shouldn't be working at more than 145 based on my age (26), but even poking along at warmup level takes me higher than that.

My resting heart rate is about 96-100 bpm, and while I wouldn't call myself in great cardio shape, I have been doing 25-minute Tae Bo for the last two months without too much difficulty. I do smoke, and I assume that's affecting me some. Other than that, the only thing unusual about me is that I have a huge lung capacity (always won swim team underwater-lap contests and stuff by a pretty substantial margin). I don't know if that could explain why I'm not at all winded at high heart rates?

Given that even a pathetically low level of exercise seems to raise my heart rate well beyond acceptable levels, what should I be doing about the cardio? I don't see how a workout like Friday's could possibly have done me any good in terms of burning calories or getting me in shape. I'm not kidding about the pace being slow, felt like an after-dinner ramble rather than a workout, and my heart rate was still way high. I don't want to keel over with a heart attack, either, though. Can anyone offer any helpful advice?

The sensors on those machines are notoriously poor. I would suggest buying a Polar heart Rate monitor or just double check the machine by counting your pulse for 15 seconds and multiply by four to get your heart rate. I think you'll find your heart rate is much lower than the eliptical says.

Hi Atlee,

Remember, your maximum heart rate is individual. You obviously have a max of over 200, which is unusual but fine. You have to estimate your individual max heart rate to determine your training rate.

I recommend the Polar monitors also, although it usually matches the machines numbers pretty well.

Amy

kaypeeoh: you're exactly right, the machine was the problem! Taking my pulse by hand came up consistently 40 beats lower than the elliptical. I'm taking a spin class tomorrow, and am really interested to see what the heart monitors show. I suspect that will give me a much better idea of the various heart rate levels!

You need to figure your target heart rate for the best fat burning results. Too high, and it becomes catabolic. YOu start burning muscle instead of fat which is counter productive when weight training.

Kat

I'm not sure I agree with that. The "fat burning zone" is a simplistic idea. At low heart rates, you are burning a high percentage of fat. As you increase the heart rate the ratio of fat to carbs being burned shifts. At a sprint you are burning predominately carbs. But that's not necessarilly bad. Studies show that working at 90% of max heart rate stimulates Growth Hormone, which leads to accelerated fat loss for several hours after the exercise is over.

It doesn't need to be that hard. If you can converse easily while running, you're going slowly enough to be in the fat-burning zone. Or you can buy a Heart Rate Monitor. The new ones let you program 70% of maximum heart rate. If you go too fast it'll beep annoyingly. It will also do 90%. If you slow down it'll beep.

For doing 90% on the treadmill, I crank the level up to 12% grade. Then I try 400 yard sprints with one minute rest breaks. If you can barely catch your breath and can feel your heart hammering then you're probably at 90% of max heart rate.

I was a phys ed major about 1 million years ago. One of the interesting things we learned is the researchers who did the infamous heart rate charts basically guessed at the maximum rates for training.


Superbly trained athletes will train in the high 190's but their recovery is the thing that sets them apart from us "mortals." I can push my heart rate up there but as I am getting oler my recovery is taking slightly longer. I used to be able to get up to 180 and down to 100 within 1 minute. Now I get up to 180 and 1 minute recovery is 112.

For some other bit of information. No such place as fat burning mode. If you train at "sprint" conditions for 20 minutes you will burn x calories. Now if you train at a lower, more comfortable rate without pushing for 40 minutes you will probably burn the same amount of calories you burned in 20 minutes at high level. I would much prefer to do the 20 minutes cardio at high levels myself.

I understand when physiologists study runners and running, they put the runner on a treadmill and make him breathe into a tube that connects to devices which monitor carbon dioxide. From this it's determined how much fat is being burned during the exercise. That's where the "fat burning zone" idea comes from.

But you're right, that at a given distance the same number of calories are burned regardless of pace. There was a study using two runners with about the same size and ability. One did a 4-hour marathon on a treadmill. The other runner did a 3-hour marathon on a treadmill. They each burned exactly the same number of calories but the 4-hour runner burned a higher percentage of calories from fat.

The article didn't go into it, but I guess the 3-hour runner stimulated a greater degree of Growth Hormone post-run which lead to accelerate fat loss post-run. Just a guess.