Introduction to Running Power
Often the butt of many jokes on Twitter and dismissed by many experienced athletes. I believe running power is a misunderstood technology which can provide an athlete with unparalleled insight into their training. Here I want to give a more balanced introduction to running power for those considering it. The running power meter was inspired by the bicycle power meter, which collects data from a strain gauge in a pedal, crank arm or wheel hub to calculate how much force is being applied by the athlete. This allows them to pace and race better on hills, into headwinds, at altitude and in the heat. The running power meter is not a true power meter in the respect that it is based on an algorithm, using accelerometers rather than a strain gauge. Combined with the pace at which an individual is running to generate a number measured in watts, this gives the athlete an insight into how much energy they are expending to achieve forward momentum. As a runner, I would put money on you having trained with pace, heart rate and RPE in the past. So to start with I’ll break the pros and cons of each method down to help you make the right decision for your training. RPE Rate of perceived exertion is how hard you feel you are running, whether you are going eyeballs out in a race (RPE of 10) of gently jogging along on an easy run (RPE of around 4). It’s an important skill to develop for runners of all abilities even if they also use technology, as data doesn’t have all the answers and can fail at any point. Pros: If you are having a bad day, RPE will make sure you don’t over exert yourself and push you towards exhaustion or overtraining It removes the risk of setting targets that are too high/low for an event Free Cons: Newer runners will struggle to understand what their bodies are telling them, and may be based on what they perceive as “getting a good workout” rather than achieving the goals of the session Will cause most runners to head out too fast when fresh, then fade as they didn’t pace themselves well enough Difficult to accurately measure training load, fitness or fatigue Requires many years of experience to dial in, and even then the best of us make mistakes Heart Rate Pros: Heart Rate gives us an unparalleled insight to how the body is performing, if your heart rate is outside of normal parameters, your body is trying to tell you something. This helps us avoid overtraining by pushing too hard Relatively inexpensive, most modern running watches will come with a heart rate monitor built in or come with a free chest strap Tracking your heart rate over time provides a valuable insight into how well your body is adapting to exercise. Cons: There is a large delay between your body’s exertion and and an increase in heart rate, so it is difficult to use it to pace races with lots of hills/surges as the feedback isn’t immediate, and your heart rate may continue to rise for up to 30 seconds after a tough section Lots of factors outside of training can artificially inflate our heart rate. A lack of sleep, high levels of stress, temperature, altitude and mensural cycle to name but a few will all affect our heart rate and may result in us running faster/slower than we should Prone to dropouts or false readings. Where 10BPM is a huge difference, battery or connection issues can leave you vulnerable Sticking to heart rate based training can be incredibly frustrating for new athletes as they feel they need to walk to keep their heart rate in the correct zone Pace Pace is probably the most popular method of measuring running intensity, and is still the most important. Let’s assume I put a running power meter on the foot of every athlete starting a 5K run. The winner wouldn’t be the one who put out the highest number of watts or the best horizontal power. It would be the one who ran the fastest. However there are issues when using a GPS watch to measure pace Pros: Cheap, comes with all fitness tracking devices, or you can use you phone The winner of the race is the athlete who runs the fastest, so it’s the purest way of tracking intensity Cons: GPS watches can lose signal, or struggle to find it in areas such as woodland or around high rise buildings Large events place so much strain on GPS systems that they cannot keep up. This resultis in athlete’s watches giving false readings, and getting out of sync with the race organiser’s distance markers. This can result in widespread confusion and frustration GPS watches are very sensitive to changes in direction. They expect you to continue running in a straight line. Making a U turn or sharp corner can leave the GPS struggling to catch up It does not take gradient or headwind into account. If you are running up or down a hill, pace data is of very little use Susceptible to headwinds Power Finally, this brings us onto the running power meter. For my money, this goes a long way to correcting the flaws of other methods: Pros: Takes hills and wind into account (new generation Stryd only) Provides advanced running metrics such as stride length, ground contact time, running efficiency, form power and leg spring stiffness Reliable data in all situations Measures distance precisely using the accelerometer inside the power meter, giving you an exact pace rather than GPS estimate Allows you to track improvements easily Unparalleled treadmill accuracy Cons: Can be confusing at first, requires time investment Expensive, at £200 for a Stryd unit, on top of a compatible watch, it’s a definite investment in your running The data can become all consuming, and athletes run the risk of losing sight of the bigger picture (running faster) Any long term
