I often find myself encouraging my athletes to focus on the metrics that really matter. Input versus Output is a great analogy for measuring fitness and understanding whether or not you're making the kind of progress with your training that will convert into real world race results. 

Some people ask me ''what cadence should I ride at'' or ''how fast should I be trying to finish?''. These questions become redundant when you start to look at the crucial metrics. If you produce the maximum output on race day in the most efficient manner then you'll guarantee yourself the best result you can muster. 

There are no prizes for the best cadence and also no prizes for a PB... unless that PB is a world record!

Efficiency is the key point here. If you produce the same power as the next guy but do it more efficiently which results in greater speed then you're more likely to win. So don't think that aerodynamics, rolling resistance and drive train efficiency are areas of focus reserved for the pros. They are all part of the efficiency equation which makes up your input versus output.

Have a read of this article to understand how you can use the measurement of heart rate versus power in your training to achieve better results. Ken