4 Tips for Using a Power Meter Wisely

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Let's face it, triathletes like their gear: high-tech, beautiful, expensive gear.

But as a coach, I have to say some gear is more useful than other gear, and a cycling power meter is the one piece of high-tech equipment that can have a significant impact on your race-day cycling performance. First it'll help you train more effectively, and it'll allow you to better monitor your effort during a race.

But as your first training session with a heart-rate monitor did years ago, using a power meter involves a shift to a new way of thinking about your efforts. You can't just slap it onto your bike and look at the pretty flashing numbers as you ride. To get the most out of your investment, you have to use it, and the data it collects, wisely.

Here are a few tricks to getting more out of your power meter. Use them and, ultimately, two things will happen: You'll get faster on the bike, and you'll focus your training on productive workouts and stop wasting time and energy on those workouts that give less bang for the buck.

1. Calibrate Before Every Ride

The strain gauges that measure your power output are affected by atmospheric conditions, so it's absolutely essential that you calibrate your power meter before every ride. If you don't, the numbers you see in the file later will not accurately reflect the work you did.

You could end up taking it too easy because the meter spits out numbers that are too high or working yourself to death because the meter is registering numbers that are lower than reality. While there is a growing number of excellent power meters on the market, here's what you need to do to calibrate each of the two most popular brands:

To calibrate an SRM: SRM refers to the calibration process as Setting the zero offset. Spin the crank backwards to wake up the power meter. Press MODE and SET simultaneously so only two numbers appear on the screen. Spin the crank backwards until the top number stabilizes, then press the SET button to make the bottom number match the top number. Press MODE to exit, and go for your ride.

To calibrate a PowerTap: Saris calls this process Zeroing the torque. Toggle the MODE button until you get to current watts on the computer. Hold down the SELECT button until the word "watts" disappears. Torque is now being displayed. Now hold down the SELECT button until the value reads zero. Then press the SELECT button once to exit the function.

2. Download the Data

This point sounds obvious, but it is the number one issue my fellow coaches and I encounter with athletes who own power meters. The handlebar-mounted computer may give you some average and max data from your ride, but there's much more valuable information within the actual file.

A power file can tell you how you're fatiguing during intervals of different intensities, which in turn reveals specific areas within your cycling fitness that need attention.

For instance, you might have great average power for five-minute efforts but low power numbers for 30-minute efforts (as a triathlete, you want the opposite scenario). You have a tool on your bike that can save you a tremendous amount of time and energy by telling you when you've done enough work and when it's time to rest or focus on your swim or run, but if the data never makes it out of the power meter it's only marginally useful.

3. Use Your Kilojoules Wisely

The two main types of information your meter provides are power and energy, and many people focus only on power. However, one of the biggest benefits of training with power is being able to accurately measure the amount of mechanical work you're doing, which, by estimation, is approximately equal to the number of calories you're burning.

The work being done is the more important of the two variables because it allows you to adjust the length and intensity of your rides and achieve the training load you're after by accounting for the impact of headwinds, tailwinds, climbs and descents.

For instance, your workload for an Olympic-distance triathlon bike leg might be 1500kj in two hours. Thus, at some points in your training you might want to do 1500kj rides. But a hard 1500kj ride could take two hours and a 1500kj endurance ride could take three to four hours. It's important to know how hard you need to go and when you need to stay out longer, or go home earlier, to accomplish the desired workload.

4. Optimize Your Aero Position

There is a range of methods you can use to evaluate your aero position on the bike, and the level of accuracy tends to vary with price. Wind-tunnel testing is at the top of the range, followed by power-meter testing on a velodrome. (Slapping clip-on aero bars to your handlebars the morning of the race is at the bottom of the range.)

The method readily available to any athlete with a power meter is to ride a set distance on the road at your race pace. A half-mile stretch of clear blacktop is all you need. Assuming the wind and humidity are the same each time you ride, you'll be able to analyze the way your power output changes with each modification to your riding position.

You'll be able to figure out whether moving your bars lower or your saddle forward actually makes you faster. Sometimes it doesn't, because the most aerodynamic position can actually hinder an athlete's ability to produce maximum power over a prolonged ride. Odd as it may sound, you might go faster with a slightly less aerodynamic position—and your power meter can tell you.