Today’s file analysis is relevant for runners/triathletes who are considering running to power. Whilst the technology is relatively new (around 3 years), the insights from running with power are undeniable.
Qualifier – running power curves look different to cycling curves and are not comparable.
The image shows two files from the same athlete. The first file is from a 5km Parkrun which was a personal best for the athlete. Pink is power, red is heart rate and green is pace. You can see how evenly paced the run was (flat terrain). You can also see the lag in heart rate coming up to threshold, which is a normal response. This is why heart rate is a difficult metric to train to.
The athlete ran the 5km in just over 15 minutes at a power of 276W. From this, and using WKO5 analysis it is possible to determine that his critical power is 273W for 31 minutes.
Move from this to the second file which is an 8km cross country race which was completed in 29 minutes. The athlete went out way too hard to try and stay with the lead bunch, with the first 2.5 minutes done at 307W. This has been marked on the file. The start was uphill, hence the slower pace (green). Heart rate again demonstrates the lag coming up to threshold. For these reasons the athlete could not rely on either heart rate or speed to guide him initially. Power, however, could have done this.
The athlete chose to ‘run like a Kenyan’. For those not familiar with this term – many Kenyan runners go out really hard in races and try to hang on. They know they will probably blow up. But they do it anyway. Each time they do it, they may hang on a little longer. Until ultimately they will pull off a victory.
Theoretically we know this athlete should be able to hold his critical power of 273W for 31 minutes. But you can see he only held 253W for this race because he went out too hard. And it is not because he was not trying. You can see that from the average heart rate being higher in the cross country race than it was for the 5km PB run.
Lesson learned? Perhaps. Sometimes it is good to put it all on the line and not die wondering.