Watching the Wheels Go By
Stephen S. Cheung, Ph.D.
Associate Professor, Dalhousie University
So if you’re like me spending your winter off-season dressing up like Bib the Michelin Man and doing extra-curricular resistance training by constantly shoveling your driveway of the white stuff that Bruce Hendler wrote so nostalgically about last week, you’re probably sticking weather voodoo pins over California and the rest of the warm parts of the planet right now. The off-season is great for cross-training and all, but your first passion is the bike, and indoor cycling can easily drive even the most hardcore of us to desperation. Rather than take it out on poor Bruce, why not devote some of your trainer time to working on optimizing your position on the bike?
While aerodynamics is critical (go ask Laurent Fignon about Le Tour ’89), the other equally critical part of the speed equation is maximising the power that you are able to generate in any given position on the bike. It’s no good to have your elbows tight and low if you can’t breathe or use your hips in a stable manner, resulting in a much lower power output at lactate threshold (the point right below where you’ll blow up), which is the name of the game in time trials and steady efforts (e.g., making or maintaining a breakaway).
How do you turn your indoor trainer into a testing rig? First, go write and thank Santa if he dropped a power sensor in your stocking. Barring that, you can also use a set of rollers with resistance, or even any type of mag or fan trainer. The key to testing is repeatability, so keep the equipment and testing conditions identical between tests. For rollers, make sure you use the same wheelset with the tires inflated to a consistent pressure for each test. For trainers (you will need a rear wheel speed sensor), do the same and add a coast-down test to standardise the pressure exerted by your tire against the resistance drum. How to do this? After warming up with light pedaling for about 5-10 min in order to warm and heat up the tire, spin up to a standard speed (e.g., 40 km/h). Then stop pedaling and time how long it takes for the wheel to stop spinning. If you can standardise this time for all your tests, then you can use speed as a substitute for power output.
What you want to do is find a position that allows you to have as high a power output/speed at a heart rate near TT pace while still maintaining good aerodynamic form (feel free to preen like Mario and have a mirror nearby!). I would focus on not only your time trial position but also your position with your hands in the drops and probably also on the hoods. The standard rules of only making minor adjustments (no more than 0.5 cm of saddle height per two weeks) applies, which makes the off-season trainer time ideal for position analysis. Good luck, and remember that your new test rig can also be used to test your fitness as the season progresses!
Stephen Cheung is an Associate Professor of Kinesiology at Dalhousie University in Halifax, Nova Scotia, Canada, with a research specialty in the effects of thermal stress on human physiology and performance. He has been an avid roadie since beginning university in the mid-eighties, and still has non-indexed downtube shifters on his winter bike and wool jerseys hanging in his closet. He can be reached for advice or comments at firstname.lastname@example.org