Question: This has been bugging me for the 20 years I’ve been in cycling. Coaches say you need a smooth pedal stroke, which is typically defined as even power transfer through the complete turn of the cranks. But I still haven’t seen any evidence that a “smooth” rider is actually more efficient than a “masher,” except maybe in a time trial. Are there any studies proving that a “round” pedal stroke is better at converting body energy to pedal energy? — Scott B.
Coach Fred Matheny Replies: You bring up a good point, Scott. It’s always fun to get probing questions like yours because it makes me think again about subjects I’ve been pondering since the 1970s.
I’m wary of cycling studies, although I read them frequently. The main problem is that lab conditions are rarely transferable to the road. Also, the number of subjects is often low and they may not be trained cyclists.
If you do a search of the literature on nearly any subject in physiology, you’ll find studies that “prove” both sides of the question and anything in between. In my skepticism, I often think that studies only prove that people need to do studies to get their Ph.D.
I’m not sure it can be proved that a smooth rider is more efficient than a masher. Cycling efficiency, as exercise physiologists define it, has little to do with the pedal stroke and a lot to do with the workings of the muscle on the cellular level. Efficiency is less a matter of style than of enzymes.
However, there are plenty of practical reasons to pedal smoothly. They include saving your knees, conserving energy and minimizing dangerous wavering when near other riders. Aesthetics count, too.
You’re right that smooth pedaling is more important in a time trial than in a road race. The reason has to do with differences in power production.
TTs require a steady application of force over an hour or so. A smooth stroke saves energy because the force required is steady for the distance (except for the turnaround or any particularly steep hills). Studies have shown that a smooth stroke means less variation in wattage during each individual stroke to produce a specific average wattage.
On the other hand, look at how road races or crits are won. Good riders hide in the pack and use as little energy as possible until the crunch comes. Then they explode, either to establish a break or sprint for the win. Mashing is how you get maximum power for short periods.
Power production is an area where there are good studies because data has been collected on the bike during elite competition. Leading the way is Allen Lim, who during his doctoral studies found that a road race winner usually has the lowest average power for the race but the highest spike of power production when the winning move takes place.