Quantifying Improvement (with or without a Power Meter)

Often times when people start training they expect to get faster, noticeably faster right away. I’m guilty of this, sometimes after a long ride I dream about how much faster I’ll be because of that. It doesn’t work like that though. Sure there are sometimes where you have a breakthrough moment, but for the most part improvements are slow and steady. If you don’t keep a good log you might not even immediately notice them. There other issue is how do you measure improvements? I have three methods of measuring improvement, ranked in terms of highest, to lowest accuracy:

  1. Power meter data, over time
  2. Speed on a bike trainer, over time
  3. Speed on the same steady climbing course, over time

The power meter is the most accurate, with a direct force measurement device you can know your exact output on every ride with +/- 1.5% accuracy. Then through semi regular FTP testing, standard workouts such as 2×20’s, your normal everyday riding/training/racing, and power trend charts (such as the one pictured below) you can see training progress.

A Power trend graph, showing 5, 20 and 60 minute power in terms of w/kg over time.
A Power trend graph, showing 5, 20 and 60 minute power in terms of w/kg over time. We can see that this athelete has been steadily progressing and then had a ‘breakthrough’ moment. Trust, but verify those data anomalies!

The second option is actually quite similar, the major downside is that riding on the trainer sucks. With a trainer setup similarly everytime (tightened down the same amount, same tire) the trainer can be a fairly accurate proxy for power. You don’t ride the trainer everyday though, and you certainly don’t ride it in your races where you often can get the ‘best’ out of your body. However, through regular testing you can see progress as if speed goes up on the trainer and everything is setup properly so should power. In fact some, many trainers have known power curves and using tools such as TrainerRoad or PeriPedal, you can get an estimate of power output.

The last option is the least accurate, but can paint a decent picture of improvement  One of the problems with riding outside is that even on the same course, the air pressure, humidity level, wind speed and direction all affect speed.  If you wear a different jacket, but output more power you might be slower because you CdA (coefficient of drag area) is higher. It is however better than nothing! If you can find a long hill (10-40 minutes, greater than 5% ideally) where aerodynamics affect your speed far less than else where you can actually get a very accurate proxy for power. For a long time professional cyclists would use climbs such as the Col de la Madone (near Nice, France) as indicators of their fitness. It can be a great and rewarding way to test your progress. If you don’t have such a course nearby, you may be tempted to just use the same course for testing, and this can work ‘ok’, but it will be VERY variable. Speeds will change drastically based on wind, clothing,  pressure systems. Unfortunately if you don’t have a power meter or a mountain to climb, the trainer is your best option for measuring fitness.

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