Training

Cyclocross power analysis: Slipping tires, run-ups, and short bursts add up

When some of your watts go straight to the mud flying off your rear wheel, you know it’s important to control your power carefully.

Member Exclusive

Become a member to unlock this story and receive other great perks.

Start Free Trial

Already a member?

Sign In

Cyclocross brings a unique set of demands on a cyclist: Competitors must be able to create quick bursts of effort over small obstacles or leap off the bicycle and run while carrying it for sections as long as 30 seconds, all the while maintaining a pace at (and above) FTP for 40 to 75 minutes.

Power meter files from ’cross races typically show an average of 20 to 40 watts below the actual FTP of the athlete. One reason for this is that there is so much downtime spent coasting down a technical hill or running with the bike. The other reason is that many of the courses lack good traction because they traverse mud, sandpits, and the like.

A cyclocross power analysis

The ability to put the power to the ground skews the power down, and one has to take this into consideration when reviewing cyclocross power files. Because of the running and coasting sections of the course, it’s also hard to determine the exact muscular demands of cyclocross. Through cadence and power analysis, we know a cyclocross race largely involves slow pedaling and higher force, but other combinations of cadence and force are also heavily involved.

In some ways the power file from a cyclocross race can resemble the power file from a criterium with stochastic power spikes, easily discernible laps, and big “race-winning” types of efforts. But cyclocross power files have some interesting differences, including power bursts, periods of reduced power in each lap, and the overall training stress accumulated. Keep in mind that power is not recorded when a rider is dismounting, running, and remounting, but this obviously contributes to the physiological (and technical) demands of cyclocross.

One thing that is important to identify in a cyclocross power file is the number of watts above FTP and the length of each of these efforts; in other words, how many “matches” the racer has to burn. A cyclocross match is a little different from a match in a road race or a criterium, however, because most likely the racer is already at his or her FTP when the need to do a hard effort arises. In this case, the matches are more like bursts of flames coming up from an already raging fire! Identifying these “flames” and being aware of their intensity will allow you to train more specifically for the kind of effort that cyclocross requires.

The 30-30-30 workout replicates race efforts

After reviewing hundreds of cyclocross race and training power files, we began advising that cyclocross racers incorporate a special workout into their training. We call this the 30-30-30 workout because it involves 30 seconds at 150 percent of FTP, 30 seconds of coasting (0 percent of FTP), and 30 seconds of running. At 30 seconds, the anaerobic capacity system is utilized, but the neuromuscular power requirements are reduced. The 30-30-30 workout is done continuously for 10 minutes. Rest for 5 minutes between intervals, completing three to five 10-minute intervals, and then cool down.

Training for the demands of the event is highly applicable here. The 30-30-30 workout is good training for cyclocross because it addresses the specific need for strong anaerobic capacity along with the need for highly tuned technical skills (dismounting, running with the bike, and remounting smoothly). In addition, cyclocross demands a strong FTP, so be sure to include workouts that develop your FTP. We recommend doing four efforts at FTP for 10 minutes each, or three for 15 minutes each, or two for 20 minutes each, in order to get in the needed threshold work in one of your workouts each week.

Train your strengths and weaknesses

Sam Krieg, a coach for the Peaks Coaching Group and an elite ’cross racer, says the 30-30-30 workout is a favorite. He likes “the structure it provides” and “the nearly identical similarities” to his ’cross races. “It forces me to go hard for the entire 10-minute set,” he said. Kris Walker, the national champion in the 2009 masters (45–49) time trial and the 2008 and 2009 masters cyclocross event, also found these workouts helpful, saying, “As a classic steady-state rider, my forte is my ability to hold a constant power for the entire event, and cyclocross is very challenging to me because I have to train my weakness, anaerobic capacity. After reviewing my power files with Hunter, we were able to determine just exactly how much anaerobic work I was going to need in order to be on the top step of the cyclocross national championship podium.”

Cyclocross is another discipline in cycling where racers are using power meters to train more quantitatively and also more specifically to the demands of the race. To a large degree, the improvement that can be made with power meters in cyclocross hinges on the athlete’s ability to mimic the demands of upcoming ’cross races and develop training routines for them accordingly.


Adapted from Training and Racing with a Power Meter, 3rd Edition by Hunter Allen, Andrew R. Coggan, and Stephen McGregor with permission of VeloPress.