Power behind the Tour: Climbing
Posted by Matt Moran on Jul 12, 2012
Hopefully you’ve been enjoying the Tour de France as much as we have, particularly now that we’ve entered the high mountains and the General Classification challengers have come to the fore. We’ve been looking forward to seeing some of the data files supplied by the guys at Training Peaks from the likes of Jani Brajkovic who finished 8th on yesterday’s difficult stage in the Alps.
Some numbers from Jani on yesterday's stage via Training Peaks:-
- 60 minute Normalized Power – 322W (ascent of Col du Glandon)
- Stage Normalized Power – 307W
- Power to Weight Ratio - 4.5w/kg
Now, jump on your Wattbike, and after a warm-up, see how long you can sustain 322W for – it’s a crude but very illustrative way of understanding the performance levels of pro riders at the highest level.
In addition to the numbers we’re also interested in the technique of pro riders when they climb. What’s really obvious is that they rarely stand out of the saddle, and if they do it’s generally to stretch their legs and relieve the pressure for a few revolutions. If they stand to attack you’ll see that they quickly revert to a seated position once they have a gap and increase in speed.
So, why climb seated? With the Wattbike we can illustrate why very easily, via the Polar View, our unique real-time pedal technique analysis. If you’ve not seen the Polar View before then take a look at our guide to what the different pedal shapes mean. What we see from elite riders is a smooth and consistent sausage shape, as seen below from a rider who has participated in the Tour de France. Here we see 400W produced at 90 cadence.
So what happens when a rider gets out of the saddle, well, I jumped on my Wattbike this morning and did some out of the saddle efforts. First thing to notice is that it is very difficult to maintain a smooth application of power, which inevitably results in an increased heart rate (my heart rate jumped by 20bpm whilst my speed only rose by 2kph - we can safely say that it was not worth the effort!). A lot of force needs to be put down the front end of the pedal stroke to maintain momentum and the consistently good pedal technique is all but lost, this is true for the majority of the riders. The physiological cost of this is an increased heart rate which subsequently leads to an increase in the production of lactate and ultimately the rider having to slow to recover.
Now, having said all of the above, we have seen a number of pro riders on the Wattbike who can stand out of the saddle and maintain a good pedal technique as you can see below. Looking at this example though, you can see that there is still a loss in power as the riders brings the pedal over the top of the stroke, illustrated by a pinching in the middle of the 'sausage'.. Effective climbing out of the saddle takes many years of training and is generally shown by the lighter riders who spin a high cadence when climbing.
The important point for most of us is that climbing out of the saddle brings a loss of good pedal technique and results in a detrimental physiological cost, i.e. our heart rate climbs rapidly with consequential performance loss. Climbing in the saddle does mean that you’ll need to ensure you have the correct gearing for the terrain so that you are not labouring a very high gear with low cadence, again something which brings performance losses.
Only by training on a Wattbike can the physiological and pedal technique improvements be monitored in real-time.