Crunching the Numbers

I've been exercising regularly for a long time now. I started it when (surprise) I was on Weight Watchers back in the day losing my weight, and I've kept at it initially as a means to maintain my weight loss, but eventually because I got hooked on it and enjoyed it.

Over the years my routine has changed a lot, and it really started getting crazy when I was training for marathons. As some of you know for yourselves, that involves a lot of time, and you end up working out A LOT. For reasons that aren't important for the topic at hand, I stopped running marathons and am now what you'd call a gym rat. But longing for those days of endurance, I end up spending a few hours at the gym on the weekends cobbling together a mix of strength and endurance.

In all these years I've had a lot of gadgets, but never a heart rate monitor. Until today. I used a $50 Amazon gift certificate and finally bought one - a Polar F6 in case you're interested. Today was the first day I took it out for a spin.

I have a lot of information here. From my heart rate monitor I found out that:

Run - 61:00 (10K distance)
Calories burned - 626
Max HR - 174
Avg HR - 163

Bodyworks class - 60:00 (circuit training with free weights)
Calories burned - 424
Max HR - 172
Avg HR - 132

Kickbox - 60:00
Calories burned - 502
Max HR - 178
Avg HR - 149

Total calories burned - 1,552
Total exercise time - 3 hours, 1 minute

Now of course I have to log this stuff into eTools:

Jogging (oh how I hate that term) - 7 Points
Circuit training including some aerobic work with minimal rest - 7 Points
Kickboxing - 7 Points

Total Points Earned - 21

If I were to (ahem) log my activity on a free website that tracks calories, I might use their database to select activities, just like I would on eTools. Hypothetically if I were to do that at, oh I don't know, SparkPeople as an example, here's what it would tell me:

Running 10 min/mile (I was at 9:49 close enough) - 575 calories
Circuit Training - 460 calories
Kickboxing - 623 calories

Total calories burned - 1,658

Here's one last batch of data. My heart rate monitor tracks my exercise intensity level, since it knows my heart rate. Of the time I spent working out today, here's how it breaks down:

Low intensity - 41 minutes
Moderate intensity - 22 minutes
High intensity - 121 minutes

If I log these in eTools using the little calculator, here's what it comes up with:

Low - 1 Point
Moderate - 1 Point
High - 14 Points

Total Points earned - 16 Points

So. What did I learn from all of this? Databases with activities may not be the most accurate way to assess your calorie burn/effort expended/Points earned. While the SparkPeople database wasn't too far off, it still overestimates my calorie burn by about 100. If it does that today, presumably my totals for the week would be overstated as well. Using the database on eTools, I'm giving myself credit for 5 extra Activity Points - a big deal if I'm planning on swapping them for food later on tonight, less so if I'm not.

Basically, what eTools and SparkPeople (and the read out on the treadmill) can't tell me is just how much effort I'm expending. Let's take the run as an example. A lot of people think running is hard, and it is to some extent. But I found it interesting that in all of today's workouts, what spiked my heart rate the most wasn't the run, it was kickboxing. It was probably that 2 minute "Turbo Kick" portion where we're doing jumping jacks, burpies, and all sorts of high tempo stuff in quick succession. The run I did today was for endurance. To run an hour. Not to run balls to the wall fast.

I'll save that for the Iron Girl 10K on May 8th. We'll see what my heart rate is that day!

In short (too late!) I guess what my conclusion is...is why didn't I get one of these sooner? It does my accountant's heart good to sift through the numbers.

By the way, it strikes me that this is all so appropriate given last week's topic of self monitoring. I told you to go out this week and maybe track something you never have before. And here I am doing the same thing!