Adventures in heart rate

Update: Steve and I are now members of Gold’s Gym. We pulled the trigger tonight and signed up. I am still leery of not having free parking between 8-5, but I suppose I will have to deal with it. An unexpected perk: the free parking before 8am and after 5pm is valet. Bonus! Steve is there running right now, so I can’t wait to hear how it went when he gets home.

Warning: what follows is a totally geeky heart rate monitor post. If you don’t care to know every detail of my heart rate during my run this morning, you can probably stop reading right here.

I have owned a Polar Heart Rate Monitor for at least five years. I have used it a handful of times, just for fun. I have always been to lazy to actually figure out how to use it as a training tool, so in the drawer it sat. I busted it out earlier this winter when I had high hopes of becoming a spinning maniac on the bike trainer this year. I did the 30 min HR test, which may as well have been called the to hell and back you will be drooling and snotting all over your bike and want to die but not before nearly puking workout. From that little gem of a workout I was able to determine my HR zones on the bike. I put this wonderful information to use exactly one time before I threw in the towel and decided I would not be biking until spring.

Fast forward to Tuesday, when I came across this article by Mark Allen. I was fascinated. Please read it if you are interested in a way better description than I am about to give. I always kind of knew the basics of HR training, but I never had it explained to me in this way so clearly before. Basically what he says is that you need to use your HR as a gauge to develop your aerobic system. There are three components of training for endurance events: strength, speed, and endurance. The first two are straight forward. To gain strength you spend a couple of days a week in the gym doing a full body strengthening routine. To build speed, you do focused interval and tempo workouts that train your body to move fast. To develop endurance means slowing things down enough during training sessions to develop the aerobic system. Very few endurance athletes take the time to do this because it means running slow enough to keep the heart rate in the aerobic zone. Sometimes this pace ends up being much slower than the athlete is used to running, even on their “easy” days.

Allen provides a formula to estimate the number for your max aerobic heart rate, or the magic number to keep your heart rate under during aerobic training.
1. Take 180

2. Subtract your age

3. Take this number and correct it by the following:

-If you do not workout, subtract another 5 beats.

-If you workout only 1-2 days a week, only subtract 2 or 3 beats.

-If you workout 3-4 times a week keep the number where it is.

-If you workout 5-6 times a week keep the number where it is.

-If you workout 7 or more times a week and have done so for over a year, add 5 beats to the number.

What is so magic about this number? Your max aerobic heart rate is the maximum heart rate you can workout at and still burn mostly fat for fuel. If you consistently workout above this number, you are essentially training your body into a chemistry that can only burn carbohydrate for fuel. Since your body is not able to take in and process an equal number of calories that you burn per hour in an endurance event, you can see where this would be a problem. There will be a point where you will simply run out of fuel.

Mark Allen describes how he started to keep his heart rate under 155 while running, and his pace was a full three minutes slower than he was used to running in training. After a few months of running this way exclusively, he was able to run as fast as he used to while still keeping his heart rate under 155. So now he was running at paces that used to take him to his max heart rate while maintaining his heart rate in the aerobic zone. Cool, huh?

I’m sure if you are a runner, you have heard the saying that most people run their hard runs too easy and their easy runs too hard. I was sure that this would apply to me as well. I hate running super-slow, and I know I sometimes pick up the pace a little too much on my easy days. According to the formula above, my max aerobic heart rate should be somewhere between 150-155 bpm.

I decided to dust of my heart rate monitor and wear it for my tempo run this morning, just out of curiosity. I wanted to find out at what pace I would go anaerobic. I started at an easy pace for my warm up. I fully expected to go over 150 bpm right away, but I did not. I stayed in the 130’s for quite some time during my warm up. I slowly increased the pace, and to my amazement I didn’t hit 150 until I was down under 8:30 pace. This tells me that my easy runs have probably been right on pace-wise.

I was interested to see what would happen when I cranked up the speed. My workout today called for 5 miles at tempo pace, which for today was 7:20-7:30. I started off at 7:30 pace, and the number climbed a bit, but very slowly. I stayed in the low 160’s for quite some time. Probably half-way through the tempo miles I hit 165. From there I hovered between 165-170 for a while before I sped up to 7:20 pace. Then I think I cracked 170 and stayed there for the duration.

During the cool down things got interesting. When my 5 miles were up, I immediately went down to 8:00 pace. I stayed there for 1 mile, during which my heart rate barely dropped, except for when I had to stop and re-start the treadmill. Once I went down to 8:20 pace, it still only dropped a couple of beats at best. It wasn’t until I was done running and slowed to a walk that my heart rate plummeted. I was back to 130 within 1 minute of walking.

Here’s where I had a light bulb moment. Even as I was slowing down at the end, my heart rate was barely dropping after my 5 mile hard effort. Now I get what happens when you go out too fast in a marathon and end up crashing and burning later. Once you get your heart rate too high, it’s really hard to bring it back down and keep it within that aerobic zone. I could be totally wrong on this by the way, but it makes sense in my head so I’m going with it.

I am going to wear my HR Monitor for a while when I run and bike, really just to gather information. I think I am convinced enough to incorporate some heart rate based training once Ironman training begins. Sorry about the long-winded and probably really boring and nerdy post. I promise to be more fun next time.

Do you ever train with a heart rate monitor?



Filed under The run

2 responses to “Adventures in heart rate

  1. All good info! I never use a heart monitor – tried it once, but the chest strap drove me crazy. I probably should though, I can guarantee my heart rate is higher than where it should be… I can “feel” that much!

  2. omols

    Ha I love the cats. Very interesting. I sometimes run with my Garmin and the HR strap but I have no idea what it means, so this was helpful. 🙂