For access to all of our training, gear, and race coverage, plus exclusive training plans, FinisherPix photos, event discounts, and GPS apps, sign up for Outside+.
Running power meters haven’t gained sport-wide acceptance—yet. But if you’re power-curious, coach Jim Vance is ready to make you a full-on convert.
The power meter has transformed how cyclists train and race since the first one appeared in the late ‘80s. It quickly surpassed every other training tool because it delivers an objective, repeatable assessment of overall fitness. Unlike heart rate, for example, which external factors like fatigue and hydration can affect, power is absolute: It always measures your output regardless of how you feel. In fact, the advantages of the cycling power meter are so great, the margin of error so small, and the cost so generally reasonable at this point with at least one meter starting as low as $100, that there’s really no reason not to use one.
Now the tech is busting into the running market, and while it’s not yet as accurate, the potential advantages are something to get stoked about. Vance explains some of them and outlines how to get started for those not afraid to be power running pioneers.
The 8 Biggest Benefits
Boost your training specificity
Simply stated, in order to become better at a specific task, you must practice or train that task. Power meters help us see how well our specific training is improving our fitness because we can easily compare workouts—do the same workout twice, look at your power numbers, and it’s easy to see if you’ve upped your output, your efficiency or both.
Improve your running technique
Imagine making a small change in your run form and seeing a major change in power (good or bad). A running power meter can help you understand which aspects of your running technique you need to focus on and which you can improve or even abandon. It also is a huge asset late in a race, when you may be tired and need help to stay focused on going as fast as you can.
Predict a fitness plateau
When the number stops going up during key assessment workouts, you’re plateauing.
If you get injured, you can use your power meter measurements to understand exactly how much fitness you’ve lost, or better yet, bolster your confidence by showing you how little fitness you have actually lost.
Nail your power-to-weight ratio
Your power meter will identify your power-to-weight ratio, which can tell you a lot, including your ideal racing weight. If you’re looking to break 3 hours for the marathon, for example, reaching a certain power-to-weight ratio might be a very effective metric on which to base your training and diet.
Understand speed per watt
Possibly the biggest advantage of a power meter is a better understanding of how the watts you produce are converted into speed. This insight into your running is something you could never measure until now.
A power meter can help you establish and maintain the correct pace, even on courses where establishing the right rhythm is difficult. For example, if you’re preparing for a hilly course, your power meter can help you dial in the exact output you need to hold throughout the varying terrain.
Know when to open the throttle
Let’s say your race is going really well, perhaps even better than expected and you feel like you’ve got more you can give. Your power meter can give you an objective assessment of your running condition and can help you determine—even in the middle of a race—when you have the form to open the throttle.
Presenting three workouts that use the technology best.
Jim Vance’s 3/9 Running Functional Threshold Power (rFTPw) Test
You will run a 3-minute all-out segment and a 9-minute all-out segment with a rest period in between.
Warm up 15 minutes, preparing for a hard effort.
Start recording your power and run a 3-minute interval at maximal effort. Save your workout.
Recover with a 5-minute walk, 10-minute very easy jog, 5-minute walk, 5-minute easy jog, and 5-minute walk (30 minutes total).
Start recording your power and run a 9-minute interval at maximal effort. Save your workout.
Cool down 10 to 15 minutes.
Add the average power for each interval. Divide the total by 2. Multiply by 0.9.
This result is your estimated rFTPw value, which you can use to set your running power zones for training and racing.
You can run this workout using heart rate or RPE zones, but using a power meter and Jim Vance’s Running Power Zones will illuminate the efficiency or energy waste much more clearly—and on any terrain.
Run easy in Zone 1–2 for 10 to 15 minutes, then build to a moderate speed on the edge of comfort/discomfort. Look at the power zone you are in, likely Zone 3–4. Stay in that zone, but find a way to go faster. Push that envelope, trying to be quicker without raising your watts. It’s a balance of trying to hold or increase speed with technique. Focus on your rhythm, cadence, forward lean, soft foot strike, relaxation, eyes and head position. Finish the run with 10 minutes in Zone 1–2.
Constant Power Run
This workout is a mental exercise that will teach you invaluable lessons about how power works and how power relates to pace and effort. Choose a course that you know well, preferably one with varying terrain like some gentle rises or rolling hills. Select a power number in Zone 3, which is equivalent to tempo run pace. Run the course while trying to maintain your power number. This workout is much harder than it sounds, and you will feel the effort when you finish. Think about when you had to back off and speed up. Consider why the workout is harder than you might have expected.
Pick your weapon
There are currently two run power meters on the market: Stryd ($200) is a small pod that clips to your shoe. Using accelerometers and sensors, it measures your acceleration and deceleration in many planes along with vertical travel, then converts these numbers to running power. The other option is RPM2 foot beds ($500). These measure power at four places on the insole and can be used for cycling or running.
Adapted with permission of VeloPress from RUN WITH POWER by Jim Vance.