Wednesday, February 16, 2011

Counting Chickens, Mad Scientist Style

The view from my bike
CompuTrainer Real Course Video (IM St. George)
I thought long and hard about writing this article because I don't like to jump the gun in declaring success in any aspect of my training for fear of impending race disaster. The reason for this is because in the past, statements such as "my training is going well" or "I've noticed a measurable improvement in x, y or z,"  have caused the planets to instantly align against me and anger some cosmic deity who will then extend a giant hand from the sky and thwack me down.

In light of this, blabbering about increased speed or fitness without repeatable (or race) evidence has become somewhat of a no-no for the Disaster Magnet. But this week, after analyzing performance graphs of my weekly long rides on the CompuTrainer (CT), I've discovered something rather neato - something that might, ever-so-slightly, fall into the "progress in cycling" category.

First, a little background. For the last six weeks I've been doing three bike workouts per week as part of a "CompuTrainer Challenge" among a group of local cyclists and triathletes. My workout intensities are all based on my FTP (Functional Threshold Power) - a wimpy 196 watts - obtained in a time trial in January. Two of the weekly workouts involve intervals at paces from tempo (76-90% FTP) to anaerobic threshold (91-105% FTP) to VO2 max (106-120% FTP). The third weekly workout is usually a long ride of 1.5-2 hours on the trainer to be done at an average power output of 76-90% FTP.

Because my first race is very early in the season (May 7) and it's an Ironman, I've replaced the weekly "long ride" with my own "very long ride" (double-it-and-add-some) of 4-5 hours. For several of these, I've ridden the simulated Ironman St. George (IMSG) course from Racermate's library of Interactive Real Course Videos. The most recent was this past weekend - February 12. Because I'm a geek (some use the term "mad scientist"), after Saturday's ride, I could not rest before coming up with a way to compare my performances from these same-course rides. (Note: doing things like this have illustrated to me the power of the CompuTrainer as a training tool. They have also illustrated to me my husband Jim's mad skills at Microsoft Excel, my lack thereof, and all the reasons I find Excel to be a maddeningly-frustrating program.)

I plotted all sorts of data for several rides on the CT IMSG course - power, heart rate, speed, cadence, etc. versus miles and time. I decided the graphs I like the most, i.e., that make the most sense to me, are the ones that compare power and heart rate versus time or miles. This way, I can see exactly what happens each time I ride the same course. With Jim's help, I now have a single plot - see below - of power (left y-axis, upper data) and heart rate (right y-axis, lower data) versus miles for three CT IMSG course rides. Two were in January and one was this past weekend. Note on January 15, the blue line, I only completed about 56 miles of the 67-mile course (also known as "getting to the top of the BIG hill").

Power (upper data) and Heart Rate (lower data) vs. Miles for rides on same CT course (click on image for larger version)
 Note: data was smoothed by simple averaging of nearby points
In comparing the three sessions, I try not to focus on speed because it depends on the CompuTrainer calibration, which might change from one workout to the next (note in the table below that my average speed on Feb. 12 is lower than on Jan. 22, and yet my average power output is higher, and on Jan. 15 my speed would likely have been higher had I made it to the downhill portion of the course). Still, my ride averages were as follows:

AVE:Power (Watts)Heart Rate (BPM)Speed (mph)
Jan. 1515713915.6
Jan. 2215614517.0
Feb. 1216313716.9

So, then, the big question: does this graph and table indicate progress on the bike? I'd like to think so and here's why:
  • My latest ride, Feb 12 (red line), shows the highest power throughout the ride, especially in the late stages (close to 4 hours effort). In comparison, the first two rides were only a week apart and even though they were different in length and time, my average power for each ride was almost identical.
  • The heart rate plot shows that on Feb 12, I was able to maintain this higher power/wattage over the distance/time at a lower heart rate than in January. Even during the hardest climbs (between 35 and 55 miles), my heart rate was lower in my latest ride. I'm guessing this indicates an improvement in my cardiovascular fitness.
Other than these rides on the CT IMSG course, my regular workouts have not been as taxing (or next-to-impossible) as they were in the first few weeks. It will be interesting to find out if and how much the increase in FTP will be when I do my next time trial. Or better, if and when I ever get out on the road again (assuming winter 2011 comes to an end before April), I am very interested in seeing how fast I can go on my old tried and true road courses.


  1. Hmmm... I'm thinking that the only way I will be able to ride with you is if I'm on a trainer next to yours !! :-)

  2. It’s obvious that you’re becoming a better cyclist and your training plan is working. Lower heart rate AND increased power will not only give you the results your looking for on the bike they’ll give you a much better run. Assuming you take on fuel correctly on the ride, you’ll have a strong run on your way to that Kona spot.

    Great post,