A big concern among triathletes is being able to ride steady on the bike—regardless of hills or unpredictable terrain. But what is "steady riding?" And how do you maintain it during a race?
The ability to ride steady is essentially the ability to maintain a nearly constant effort, regardless of uphills, downhills, winds or other threatening terrain, with few to zero surges of power/effort. To explain why this is important let’s toss out some power-geekery terms:
- Average Watts: The physics of you riding your bike—rider with weight X, aerodynamics of Y, puts up Z average watts for 112 miles on the Ironman Wisconsin bike course and puts up a 6:xx bike split. "Average watts" is the physics of what’s going on there.
- Normalized Watts: A construct created by Hunter Allen and Andy Coggan, normalized power attempts to account for the fact that all watts are not created equal. The metabolic cost of watts gets much, much higher as watts increase and normalized watts tries to account for this. In short, "normalized watts" is how tired you felt after producing your average watts.
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Normalized watts allows us to compare two very different rides, and normalize them.
- Timmy does a flat ride and his average power (Pavg) is 200 W.
- Billy does a big climbing ride and averages 200 W. (Assume Billy and Timmy are identical twins on identical bikes.)
- Timmy’s normalized power (Pnorm) is 210 W, however Billy’s Pnorm is 225 W. In short, although Billy and Timmy both produced the same average watts, Billy’s ride was harder and more costly to his body. In other words, Billy’s style of riding made him more tired.
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How a Steady Ride Comes Into Play
If we divide Pnorm by Pavg we get Variability Index (VI), a measurement of how variable or "non-steady" each ride was. In the example above, Timmy’s VI is 1.05, Billy’s VI is 1.125. A low VI ride is more steady than a high VI ride.
Using these definitions of average watts (physics of riding your bike) and normalized watts (how tired you got while producing those watts), we can now talk about how we (at Endurance Nation) want you to ride your bike on race day:
The Idea: Produce your optimal average watts while expending as little energy as possible.
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