Having finally got myself a Bluetooth HRM I’ve now done a couple of workouts with it and a little bit of analysis. (I already had an ANT+ HRM but I use TR with an iPad Mini which has the Lightning connector and you can no longer get the 30 pin to Lightning connector so my ANT+ dongle won’t work with the Mini, progress eh?)
First workout was Mount Goode with its fifteen minute intervals close to FTP. Ignoring the initial minute of each interval where my HR ramped up to get to its “steady” rate then my Cardiac Drift for the three intervals sat between 3.4% and 3.9%. That’s well below the 6% drift quoted as the boundary between adapted and non-adapted.
The problem with Mount Goode is that the workout as a whole is too short and at the wrong intensity. Joe Friel in one of his Training Peaks articles reckons that you should use a workout or activity at least two hours in length at Aerobic Threshold (AeT). So today I did Boarstone.
One slight problem: at 15mins the TR app on the iPad froze, no idea why and it’s never done it before. Had to quit the app, restart and resume the workout. Only did it the once. Annoyingly this meant that when the data was exported to Strava and Intervals.icu only the first fifteen minutes was exported so I’ve had to work out the aerobic coupling values by hand, OK, via a spreadsheet.
What I ended up with were seven “intervals” with decoupling of: 4.7%; 0.16%; -0.17%; 0%; 0.33%; 0.5%; -2.39%. Yes there are two minus values and a zero in the series. I think it’s safe to say I’m aerobically coupled! Then again I shouldn’t be surprised as I’ve had nearly fifty years of endurance type activity, I’m the archetypal diesel - light the blue touch paper and … wait and watch me plod away.
So the question is: what do I do with it? Joe Friel notes:
When heart rate and pace or speed are coupled (less than 5% decoupling) for the goal duration then aerobic endurance fitness is considered to be optimal and you are ready to move on to the next stage of training-the build period.
Now my goal duration is more like 12hrs riding not three or four but I’m not spending six hours on the trainer as Friel suggests, I’ll just extrapolate the results. I’ve just started the Sustained Power Plan so have implemented that takeaway from the above quote but how else do I use this info? If I notice an upward drift (in the, err, drift) does that indicate overtraining or perhaps the potential onset of illness? It almost seems like an afterthought - “oh we can calculate this …”
Finally, is there a reason TR don’t do the calculation in the workout summary? It’s a much easier calculation than Normalised Power for example, notwithstanding the above comment.