Measuring your run

Jagannath. G.

There are many metrics that you would hear when you start running. This blog tries to shed some light on what those mean. 

Pace: The easiest "measure", which is the most commonly used one is the pace. It just means how long you take to cover a fixed distance - kilometer if you use metric; mile if you use US method. So when someone says they ran at a 6 pace average, it just means that they have taken an average of 6 minutes to cover a kilometer on average (ex: 10 km in 60 mins). It is possible to set alerts for a " pace range" in your watch.

Speed: This is similar to your speedometer on the bike/car. This measure is generally never used but just shows up on your stats on strava/race dashboards. So for the same example of 10k in 60 minutes, your speed would be 10 kph.

Heart rate (HR): This is another measure which can be used to assess the difficulty level of your run, on the go. Based on your age and fitness level (and preferably with a time trial), your heartrate is bracketed into different zones - primarily aerobic and anaerobic. The goal is ideally to keep at least 80% of the runs aerobic and the way to do it by setting alerts for HR zones within your aerobic potential. Repeating time trial and recalibrating your HR zones every six months helps! This measure further branches out into sub-measures like resting heart rate (RHR), maximum heart rate (MHR), heart rate range (HRR), lactate threshold heart rate (LTHR), etc. This topic will be expanded in detail in another write-up.

Rate of perceived exertion (RPE): This is a more simplistic and gadget-free methodology. You just assess the difficulty level of your run based on feel and decide whether you want to go easier or hard, on the go! Though this sounds the easiest methodology, any newbie (<= 2000 km run experience) is bound to actually get into anaerobic zones on these. Only a person who is pretty experienced and in good form usually is able to match the expectations of the workout withe RPE methodology.

VO2 max: As you all know, lungs take in and supply oxygen to your heart which in turn supplies oxygenated blood to rest of the body. VO2 max is the amount of oxygen the muscles can absorb. Higher oxygen intake by muscles implies higher efficiency. This is another parameter that cannot be observed on your watch while running and can be seen only in post run analysis. You cannot specifically do one workout to increase VO2 max but in general any workout that keeps your effort at 90% level for spurts (like interval runs) or any long aerobic workout helps in increasing VO2 max.

Cadence: Simply put, cadence means turn around time. It is the number of times you tap your foot in a minute. Higher cadence generally means more efficiency. This can be measured on the run, and alerts can be set with metronome in a few watches to get the cadence up.

Stride length: The average distance between two foot strikes of the same leg during your run is your stride length. So a longer stride length means that you are covering a good distance with your jump (any run can be defined as a single leg jump, repeated multiple times alternate legs). Though a good stride length is desired, this is not something that you can measure during run and also wider strides  more than what your height permits will lead to injuries.

(Note: Cadence and stride length combination increases your pace/speed. So rather than trying to increase the stride  length, go with increasing cadence.)

Ground contact time (GCT): Another of those seemingly useless measures that your Garmin throws out but actually good to understand and compare with others. The idea while running is to keep turning those legs quickly. A longer GCT means you are closer to mimicking a walk than a run. Longer GCT is used during "relaxed phase" probably when doing a hard run. Again, analysis post run is only possible but by feel can be assessed during run.

Every runner is unique and has a different height/weight/running form. It never makes sense to pit your numbers against anyone else but there are certain best practices that can be followed and some measures where we can train to reach "ideal" level - things like higher cadence, low GCT, staying aerobic, etc.

Will try to explain the different types of training runs in the next blog. Happy and injury-free running till then!!