Back on 12/30/11, I got my first metabolic test. This involved putting me on a bike, then pedaling at a steady cadence as they ratchet up the wattage. They do this until I cross my anaerobic threshold. The measurements are taken via heart rate monitor and a facemask that measures inhaled/exhaled oxygen and CO2. By measuring the gasses, we can infer how much fat and carbohydrate I’m metabolizing at any given wattage/heart rate/cadence/time. It’s a very interesting approach to measuring your limits. In my case, I wanted to measure my aerobic base and improve it.
In the December test, my fat utilization at low wattage was terrible, about 40%. This means my aerobic base was practically nonexistent. 60% of my energy at 100 watts was coming from carbohydrates! My threshold heart rate was 157 bpm and my threshold wattage was estimated to be around 320. While this was a good threshold, my body was eating itself up to that point. It was clear that I’d need to focus on base training in order to become a more well-rounded rider. I especially needed this for the longer racing we do in cat3. So I developed a plan.
The goal was to come back and re-test in 6-8 weeks after focusing on base training. I bought a nice trainer that keeps me honest and locks in the wattage range. All I have to do is pedal. One or two times a week, I’d do an hour or two on the trainer. Then on group rides, I’d really focus on that endurance wattage and heart rate. It was really boring sometimes, but the group trainer workouts helped me a bunch. Also, the slower pace on team rides helped me take it all in. I needed that.
The follow-up test
I went in for a test today (3/2/2012) and the results were crazy.
- 90% fat utilization in my lowest power/heart rate zone (up from 40% !)
- 168 bpm heart rate @ my anaerobic threshold
- 360-380 watts @ my anaerobic threshold
- Bonus: V02 max increased to 73.1 ml/kg/min (my weight also decreased 1 kg between test 1 and 2)
So what does this all mean? Well, I sure accomplished my goal…and then some. I jacked up my aerobic base and continued the hard Magnolia hill rides, which maintained my high-end strength. Based on this test and my race performances, my threshold wattage probably lies around 330-340. The 380 is just was was used to make me crack in this test. My physiology points to a pretty good vo2 max as well. Now I have new training zones, both in power and heart rate, which I will overlay on all my planned riding for March and April. My goal is to show up to Walla Walla and crush some souls!
In the end, these are just numbers. I still need to become a smarter and more controlled racer. There is so much to learn. I’m just pumped to get this base training nailed down so I can build and build into the Summer for some fast racing!
Regardless of the numbers, race performance really is what matters most. Although, I sure do enjoy experimenting on myself as a human test subject. It is my second year racing, so I had no idea about base training before this season.