Friday, July 8, 2011

Heart Rate Monitors, what are they good for?

I recently got a Polar FT7 heart rate monitor, after 25 years of training without, or flying blind as some would say. Guys like Marty Gallagher and John Schaeffer swear by them. I used mine for a while after first getting it. My opinion on them is that they are good for what they do, but I would hardly call them essential. Even when training clients, there are much better indicators of intensity than heart rate, including:
* Panic breathing,
* Degree of sweating,
* Rep speed,
* Facial expression and trapezius tension, and
* Technique degredation.

I like using the heart rate monitor as a "objective" proxy for exercise intensity. Generally speaking, the higher your heart rate is, the more intense the effort is. This for example, allows you to objectively compare the intensity of TGU vs. 20kg snatches vs. 40kg swings vs. DDR. I like it for this purpose.

What I really don't use it for is counting calories. It is not that I doubt the accuracy of it, to the limits that I understand it is an estimation, but that I really don't have any need for the information. I don't really plan diets by the calorie. If I look at what I put in my mouth, I don't know what the calories are exactly. I don't know what my basal metabolic rate is. Using what Cornell University taught me about significant digits, it would be pointless to calculate my exercise to the nearest calorie. I better way it is eat for you are going to do/what your body needs. I have never found calorie counting to work simply because they are just estimates anyway.

In common fitness parlance, they are talk about different exercise zones related to heart rate, including:

* the Fat Burning zone: 65-75% of Max Heart Rate
* the Cardiovascular Conditioning zone: 80-85% of Max Heart Rate.

I don't pay much mind to this for a number of reasons:
1) I would rather focus on doing the work instead of what my heart rate is. I can look at the heart rate after.

2) Since a relatively small number of fat calories (for most people) are burned during exercise and most are burned at rest, why would I micromanage fat burning during exercise.

3) Max Heart Rate is an estimate based on age, and while that is true for the general population, that is definitely not true for the:
* Trained or
* Sick/Deconditioned
==> Well, these are the two groups I work with the most. Since the Max Heart Rate is an individual thing, why wouldn't I treat it that way.

4) There are other better indicators of exercise intensity (see above) that are less intrusive and more illustrative.

I tried the HR monitor with a lot of different activities:
* MaxVO2 snatches: 20kg x 8 rep cadence for 30 minutes
==> Average HR: 161; Max HR: 179; Cals: 425 (14.20/minute)
* Sissy Test (325 Burpees and 325 32kg KB swings in 46:25)
==> Average HR: 170; Max HR: 184; Cals: 761 (16.45/minute), I still don't give two shits about burpees
* Lying Down -- Heart Rate: 55-58
* Sitting -- Heart Rate: 61-65
* Walking -- Heart Rate: 72-90
* KB Military Presses: Typically at the end of the workout my HR is in the 85-100 range.
* DDR: 110-150, but I hit 200 during a 5 minute boss song after doing swings.
* Continuous 24kg snatches/burpees combo: Average HR: ~ 160; Max Heart Rate: 179
* Barbell Squats: After: 110; Right Before: 77

What I have found is that the HR monitor is just a too to measure your heart rate. It does give you a gauge on intensity. It is too much of a hassle to use everyday, unless you have no clue how to gauge performance and other physiological factors. Try it out, you will learn something. But don't be a slave to it. The heart supports the performance of the rest of the body, it is not the goal. Keep it in that perspective.

1 comment:

Michael Suggs said...

Good stuff Faizal. As you know, I just got mine and it's easy to get geeked out and pay too much attention to the numbers. Listening to your body and how it's reacting is important as well. Although, it is nice to see how high you can get your HR on a certain exercise.... Thanks for your thoughts on this.