Flat or Uphill performance

It's a 'phenomenon' which I have also experienced. It's basically that uphill you just don't produce the same wattage numbers as 'easily' as riding on the flat. I experienced this the first time a year ago when I went up the Ventoux a few times. One time I tried to ride it fast as I could, but for some reason I just could not produce the numbers wrt my FTP at that time (apart from not being able to finish it because the weather went completely upside down along the climb). I could only average approximately 300 watts for one hour which is about 8% lower than FTP at that time. That ride was my 4 th ride up the mountains when I was in that region.

 

At the moment a similar discussion is going on on the wattage group. Several possible reasons for this are brought forward. I have put them below (most of them come from Alex Simmons, Bill Black, Nathan Townsend, Tom Anhalt,and if I have forgotten someone sorry!):

 

1) Different cadence / forces which lead to different application of musles

2) Different angles / joints which causes body position to change and can cause a power compromise

3) Forward/lower torso position requiring more emphasis on hip-extension (vs. knee-extension) for commencement of pedal stroke over the top and into the power-phase

4) Climbing recruits greater calf muscle activity (plantarflexion) across the bottom of the pedal stroke and consequently, slightly more force is applied through the bottom of the pedal stroke (approx 135° - 225°) which contributes to the overall power production throughout an entire pedal stroke

5) Longer tibia relative to femur equates to better climbing power relative to flat-land power. 58:42 femur to tibia length seems to be the norm ('correlation' instead of causation)

6) Different air flow / cooling

7) Power meter error and/or system biases (e.g. error due to non-round rings on crank based meters is amplified on climbs as the crank velocity variance within each pedal stroke increases)

8) Psychological / motivational factors

10) Difference between power-speed relationship on flat v climbs giving different feedback to the rider: More concentration required on the flat to maintain power

11) Different inertial load = different acceleration profile per crank revolution (it’s about double or more on steeper climbs compared to flats) = different feel and neuromuscular demand
12) ''Kinetc energy argument (energy of motion): when Climbing you have low kinetic energy, traveling slowly, gravity holding you back: your motor patterns are significantly different between time trialing and climbing. There are subtle differences in how a rider moves his or her legs and the speed at which he or she moves them. The pedal stroke is not uniform. There are many accelerations and decelerations throughout the movement which are dictated by the load'' (last part from http://cyclingtips.com.au/2013/09/climbing-and-time-trialling-how-power-outputs-are-affected/)

 

A list of multiple possible factors and hence probably not one factor being the only one that plays.

 

 

However as you also might see for yourself that indoor vs outdoor FTP may differ (for different reasons) climbing FTP vs flat (time trial) FTP may also differ. However adaptation (read improvment) will certainly come when training under those circumstances; I do not doubt that. I cannot prove it, but I think a lot of you will underwrite that if you live in a flat country and when you go and ride uphill the first few times it just feels different and it feels like you have to work your whole body; your body position (hands on the bar), different cadence, different forces on your body / legs, pedal style is different, adjustment of breathing (or at least more aware of breathing): in all it's just different.

 

As someone also put it: Performance is relative to the theater of performance. I will add to this that practice makes perfect.

 

Note: I did not take into account a possible loss of performance due to the altitude of the mountains, which might also play a role