This month like never before the cycling press is awash with power meter stories. We’ve seen price cuts from Quarq, Pioneer and Power2Max. New devices from Powertap, Rotor, and Garmin – plus several other projects somewhere between prototype and mainstream. It would be fair to say that the power meter market is progressing at a speed few can keep a track of. So where is all of this precision hardware heading? Well, we’ve been saying for years that power meters are destined for ubiquity, like heart rate monitors and cycling computers before them. In fact they are significantly more useful, so ought to achieve even greater uptake. Indeed the only thing standing between where we are now, and a power meter on every serious cyclist’s bike, is the realisation that power is absolutely key to cycling.
But why is power so important? Well it’s what we like to call “the unifying variable” of cycling performance. It’s the one thing that completely explains everything a rider has got (in terms of human output) at the same time as everything he needs (in physical or engineering terms) to achieve a given speed on the road. Speed of course is the essential element of racing, so power is becoming the language of racing. Now take a look at the diagram accompanying this post – we’ve been opening power seminars with this for the last couple of years.
Power supply is really the sum product of all physiological energy systems (aerobic, anaerobic, etc) factored by a rider’s state of motivation and fatigue. All of cycling physiology can be boiled down to “how much power can I/he/she produce” while how it’s produced almost doesn’t matter. Almost we say, because the details and complexities have a role in developing training strategies that improve output, and in the finer points of performance modelling.
Notice how we said power supply is more than just physiology. Yes, power is the product of the human body mixing fuel with oxygen, then converting that into mechanical work, but it’s more than that. There is no better metric of fatigue or psychological factors too. Power is, as sport scientists would say, an inderdisplinary factor and it’s corollaries Watts/Kilo and Watts/CdA are continually demonstrated as the greatest explanatory factors in cycling performance.
Think of power demand as the combination of 1) the demands of the event (that set of prerequisites so famously analysed by Team Sky) including course, weather, required speed; 2) the state of the rider, size, weight, etc; and 3) equipment choices. Change any one of these elements and power demands change. The key point is that, once again, they can all be explained in terms of power.
Consider these “performance questions”:
• What ability does rider X need to complete course Y in time Z?
• How will that change if he’s fitter, lighter, or more aero?
• Which equipment choices will maximise his speed given predicted conditions?
All of these question and many more can be answered with a little research, power data, and the appropriate modelling techniques.
It will take a while yet before the current wave of power meters breaks across the cycling world. But when it does we expect to see a great realisation - that power is much more than just a number reported by the most fashionable cycling accessory. To think of it like that is to be stuck in the dark ages of heart rate monitoring. No, power IS modern cycling – the language of ability, the metric of goals and objectives, and the benchmark of equipment. And as physiologist Allen Lim put it recently “power has changed the language of professional cycling”. Parlez vous power?