Critical Power: Knowing How Fast is Too Fast
1) Our final five-minute profile. This year, we’ve focused on sustained power, using the five-minute effort block to build endurance. A healthy rider should be able to pedal for five minutes continuously, regardless of age. I’d say about one-third of indoor riders can perform that aerobic feat. Closer to two-thirds in my classes… on a rainy day when the outdoor riders attend:)
2) A recent New Yorker article speaks to this phenomenon: “Indoor fitness companies, such as SoulCycle and Peloton, have reinforced the image of cycling as a high-octane cardio workout.” Indoor cycling started as a way to train for a cross-country bike ride — thank you Johnny G! As the “cardio-party” branding grew, no one ever asked “How Fast is Too Fast.” So folks started pedaling 130 rpms and calling it fast.
“[Peterson] sees the glorification of speed—personal bests, constant quantification, metrics, leaderboards—as discouraging to entry-level riders who might otherwise enjoy life with a bike.”
3) We’ve used functional threshold power to gauge aerobic effort. Many riders still struggle to maintain an intensity that allows for a multi-minute effort. “Pedal fast, breathe slow.” Few riders realize that they must learn to ride slowly before getting faster. FTP is a good barometer of aerobic power, but it can underestimate a rider’s maximum power. You simply ride within your limits for 20 minutes . . . never fully exerting.
4) Critical Power is a newer metric used by cyclists to complement, or even replace FTP. Your critical power is the watts you can maintain indefinitely. The high zone three, the low zone four, we often talk about. Steady, consistent, and demonstrable effort (see 2023 Fitness trends from Outside Magazine) is what cyclists aim for. Learn more about Critical Power here and here.
5) Once defined, a second maximum effort is needed to find your Work Prime (W’). Work prime (W’) measures the watts you can generate above your Critical Power. This metric speaks to your anaerobic engine.
“We are more than a decade into high-intensity interval and hard core circuit training––a “go hard or go home” mentality. I think we are going to see people challenge themselves to be consistent without feeling like they need to go all-out. ”
6) We’ve been working on accelerations in class. I am not advocating Critical Power per se, but the distance between your ‘normal’ pedal stroke and your aggressive pedal stroke should be noticeable. High intensity doesn’t mean pedaling fast, there does need to be a physiological response, measured in watts. Your watts will decrease as a function of time. Understanding your Power Curve, the watts you can sustain over specific durations, helps define intensity.
7) Perhaps Critical Power is too much for you. It’s understandable. Linking your fitness tracker to Strava or another fitness app can remove the computational onus. I’ve been using Strava for many years and appreciate its recordkeeping capabilities. More advanced tools are needed to capture shorter (less than a minute) efforts. When coaching others, I use GoldenCheetah for analysis.
Strava Numbers (on left) @drucycles
Golden Cheetah screenshot (on right)
8) Our banner comes from Henri de Toulouse-Lautrec. The Simpson Chain was supposed to revolutionize cycling. Lautrec was hired to market the concept. Of note is the woman cyclist pacing competitive cyclist Constant Huret behind. Pretty progressive for 1896!
9) The sprinter is the next type of cyclist in our overview. The average sprint in a professional race is 9-12 seconds. Kinda crazy. The ability to generate massive watts is what differentiates a sprinter from the rest of the pack.