Watts the future
By Joe Friel
Power. Think about it.
It’s what separates casual riders from the elite. You can be a precision bike handler, a wheelsucker extraordinaire, an elegant pedaler – but if you can’t crank when the crunch comes, you’ll be left behind.
But how can we improve our power rating? And how do we measure it? And isn’t power directly rated to out heart rate? Well, no, not exactly.
By focusing on “scientific” training, we’ve become too wrapped up in our heart rates. Many of us have even come to believe that high heart rates are the reason for training. But when it comes to racing, it doesn’t really matter how high you can get your heart rate. If it did, we’d just take everyone’s pulse at the start line and declare a winner. That would prevent a lot of suffering.
But there are very good reasons to monitor heart rates when training. On days when recovery is needed, the heart-rate monitor is an ever-present coach telling you to slow down. For long, steady rides that tax your aerobic system, the heart-rate monitor is also valuable. But for intervals, it is suspect as a good indicator of what is being accomplished. And the shorter the interval or repetition, the less valuable heart rate is.
There are other problems with using heart rate to gauge the intensity of a workout or race. Excessive heat, cold and humidity cause it to rise. A couple of cups of coffee before a ride will raise some confusion in judging intensity. To compound the problem, as a ride progresses heart rate increases even though the work-load remains constant. This is known as “cardiac drift.” Furthermore, a high cadence will produce a higher heart rate than a low cadence, even at the same rate of work. Even your position on the bike affects it. Try sitting upright versus in the drops while riding an indoor trainer sometime and see what heart rate does.