Spin Class

Update: OK, the last picture was an entire two hour ride, when the only part I cared about was a 40 minute interval. So that wasn't really fair. In fixing it, I upgraded to GC v1.3, and it makes a little bit nicer plot.

Pop quiz: Can any of you geeks tell me what is going on here, and why I am pleased by it? Get it right and there might be a star for your forehead or something. Thanks for attending.

Update on comments: What is going on? This isolation of the 40 minute effort does a better job of showing what I am bragging about. If it wasn't obvious before, the black curved line plots whatever power value you plug into the Watts box on the left. With v1.3 of GC, it's hardly even needed, as now the background has these nice rainbow-like shadings to identify power zones for the rider in question. The value plugged in to the RPM box moves the Y-axis from left to right, to the corresponding pedal velocity, based on the crankarm length input. The horizontal black line really has no purpose, as you could use the intercept of the vertical line and the black curved line to see where the watts and rpms intersect. I guess it helps you find that point on the force scale, but other than that it has no meaning and is just in the way. Where the points land in relationship to the curved line and the vertical line is what matters.

So then what is the big deal? This plot represents a cruise interval. I've been doing this workout for years, since long before I got the stupid power meter. Normally I do these on an uninterrupted, 10k stretch of flat road, and they take 15-17 minutes, depending on wind, fitness, etc. My goal with these has always been to simultaneously maintain both a fairly high effort and a high cadence. Yesterday I was just fifteen minutes into my lunch ride when I realized I was feeling good and ready to begin. With light daytime traffic, I could navigate over to my normal course without stopping or having anything else get in the way. Therefore, as a change of pace I figured I'd try to do this for 40 minutes straight, with only a slight decrease in effort from what I normally maintain for 10k.

What I like about these plots in GC is they depict the "quality" of your spin. Anyone can spin the pedals fast with no pressure on them. That doesn't do much good though, does it? This is always the issue I've had with athletes using a fixed gear or single speed to develop allegedly good pedaling technique. Without pressure on the pedals, high cadence is rather meaningless. By the same token, all the pressure in the world doesn't do much good if you're at 40 rpm. We've all seen the DWI's and pathletes (and some of us even compete with them) chugging along in their 42x13. It may hurt, but it doesn't make you go faster. In fact, one of the real revelations I had after starting to use a PM was just how badly my power fell off the map when my cadence dropped, even though the effort seemed difficult. Anyhow, if you want to be like Cancellara, then you have to not only spin, but spin with some pedal force. And that is what I try to do.

As I noted in a post earlier this week though, I've been feeling like shit since coming off my rest week. The real indicator of shit-feeling to me is when I just can't find a gear that works. I can't muscle, and I can't spin. No matter what I do, I can't make the bike go fast. This was particularly disconcerting to me this week, as up until Turtle Pond, and even last Sunday riding with the Cronoman, I felt I was pedaling very well. The work I've been doing to free up my SI joint has helped me feel more balanced, and generally "loose," which in turn helps me maintain a good cadence even during more intense efforts. But since Sunday that was lacking, until yesterday.

And that's all there really is too it. If you look at the plot, which shows just the 40 minute interval (except the few black dots), the majority of it is on the high side of the 90 rpm line. The 289w black line is the average power for the entire effort. This is only about 10w less than what I normally do for 15 minutes. In fact, the best 15 minutes of this, which came at the very end, on the road where I normally do these efforts, came in at a PR of 318, and an avg cadence of 99. And that was after 25 minutes of 270ish. But what really counts for me here is that the pedal velocity is high, but the force is still there, thus the power was made at high rpm. I'm spinning with authority.

Dougie's comment about Blue Hill is a fly in my ointment though. I've still never been able to make a good run on Blue Hill at high cadence. My best times up there usually end up being an average of somewhere between 68-75 rpm. Nature of the beast I guess. The grade is pitchy and I stand a lot. Plus at anaerobic power levels, higher cadences seems to push me closer to the tipping point. On the other hand, when I do five minute efforts on the flats, I do my best at 100 rpm or better, but the power is generally 10% or so lower than what I get on Big Blue for the same duration. On the flats I think my efforts are more of a true 5-minute VO2 max indicator, whereas on Big Blue it's 4-minutes VO2 max followed by 1 minute of totally anaerobic. Of course, we don't have a lot of 40 minute climbs around these parts, which is why Doug does so much traveling to seek them out. Next weekend I plan to try some of the longer ones we do have in New England though, and I'll see if I can climb at decent cadences too, and if it seems to help. Yes, I realize that it's how fast you go, not how you go fast, but i think after all this time I know how to make me go faster, thus I work on it. Thanks for reading and commenting.