Garmin now offers runners the ability to measure their running power, which adds a great level of sophistication to run training. Previously power measurement was almost exclusively limited to cycling, but now we have the same tech available for running. In short, a run power meter measures the power you generate when you exert power or force during a run. Scientifically spoken, it is the best way of measuring your running ability. It measures your running effort in wattage, meaning it would tell how long you would have lit up a bulb with the energy you generated. All athletes who know how training with power works, bear with us, as a simplified explanation is necessary for those of us who do not know precisely what it entails. The question is: why is it better than measuring other variables, such as heart rate or pace?
Why is power measurement better?
Power is a fixed variable, since it measures generated watts, irrespective of heart rate or perceived effort. Heart rate and pace are not fixed variables, meaning that fatigue, for instance, can lead to a higher heart rate at the same pace over the same distance, than on another day. As far as pace goes, factors like wind, road surface and elevation can lower your pace over a given distance. You can’t judge your effort to be inferior just because it is slow. Just ask any trail runner. They would easily expend more power to get up a mountain while going much slower, than you would on a flat surface, going much faster.
Measuring power has its own complexities, and it is by no means perfected, as all the variables that influence power are hard to capture. For instance, Garmin is the only company right now that allows for wind resistance to be added to their power reading. If your watch has been synced to “account for wind”, it will adapt the measurement to allow for wind conditions courtesy of the weather info it receives. (You can enable or disable this in the run power app settings) Nevertheless, as you might understand, this science is at the mercy of many other variables that are hard to control. It also needs to be mentioned that run power devices from different companies record readings that differ from each other. To get a scientifically proven power bench mark from which to depart is more or less impossible, but if you use the same device every time as a reference, it will serve the purpose of power training perfectly. You will identify trends and be able to evaluate your running prowess accordingly.
One advantage of Garmin’s run power measurement as opposed to other 3rd party companies is that power measurement stops when the watch is paused. When you pause your watch, third party devices do not know that you actually wanted to stop, and calculates the low power reading as part of your run effort.
How to interpret your running power stats.
Your aim would be to measure the highest power output, with the lowest heart rate, or at worst, perceived effort, when you run. In real life you would need to run the same course, in the same type of weather, at the same pace, at different times to compare your fitness over time. Your weight, nutrition, metabolism and all other factors that might constitute a good, or not so good run, will play a part. The end result will still reflect how efficiently your body generated power.
On the other side of the spectrum is the positive that you will be able to judge difficult run days, influenced by factors like extreme wind and elevation, in terms of power and not necessarily pace.
So how do you get your watch to measure your running power?
Step one is to download the app from the Garmin IQ store. There are 5 apps that enable your watch to measure power: Current Power, Average Power, Lap Power, Last Lap Power, and the fifth one which is called Combo Power. Combo Power is my favourite, as it is a combination of all four power data fields. The individual data fields can be added as a data field to any screen, whereas the Combo Power would get its own single field data screen. This screen will dutifully reflect all four power fields.
To record power you have to add one of the five power fields to your running app. It can be any run power data field, on any screen, but it needs to be loaded to your run app for the watch to record power.
The hardware you’d need is the Fenix 5S, the Fenix 5, the Fenix 5X, the 935 or the Chronos. These are the only Garmin devices that measure run power at this time. You’re also going to need a heart rate strap that measures running dynamics such as a the Run HR strap (old or new version), the Tri HR strap, or Running Dynamics Pod.
How to use it.
During your run you can view the data that would reflect most sensibly on your type of training, or the stats you are looking for. For instance, when you do manually recorded intervals, the last lap power would be great. When you press the lap button after say, 400’s, it will tell you the power of your last lap, and you can compare it with all the previous laps’ heart rate and pace. This will be a good indication of the interaction of four variables in the mix: the onset of fatigue, pace, and heart rate, and power. If you do long runs, average power would be a good field to watch. If you can identify a “long run” power trend, you will eventually be able to set power parameters within which you know you can sustain long runs.
All four fields at your disposal offer a different set of stats, for different reasons. After your run you can compare it with all the other run dynamics. Currently you can over indulge yourself in the 12 available parameters, as shown on the screenshot.
Garmin has put in a lot of research to make this available. Knock yourself out with the tech, but after all is said and done, enjoy every step you run for the pure pleasure of it.
(Cover photo: Oakpics)