Power versus Cadence

Danielle Santucci

Question:  I am in week 17 of the advanced HIM plan and today I did my Wed bike workout (on my trainer due to sick child at home).  I dont have a power meter, so I train based on heart rate.  My question is, during a workout such as today when Im going in and out of HR zones, what should my cadence be?  Should I be doing high cadence, low power or vice versa to stay within the appropriate HR zone? 

Thanks, Danielle

Scott Alexander

Unless the plans specifically identify a cadence range for you to stay in, you need to "self select" your cadence. What works best for you to get the workouts done, with minimal impact to downstream workouts.

Generally though, most people TRY to hover from 88-95 RPM for their rides (I'm usually on the lower end of that range). There's many discussions, both in and out of da haus, about which is best for cycling, cycling vs tri, and running off the bike like we do in tri.

Danielle Santucci

Thanks Scott. I guess since I am so new to EN I have yet to have the time to go through all the info on the website and read through the forums. I'm racing a very challenging HIM in 4 weeks (Eagleman) and want to get the most out of the training program with maximum results. So much to learn in such a short period

tgarson

@Danielle

I just want to point out one thing, your comment about high cadence, low power jumped out at me. I get what you are saying, but it is important to realize that power is a measure of work rate. That is, power is just as influenced by our cadence (rate) as by how hard we are pushing (roughly, work).

So high cadence does not imply low power, in fact high cadence allows us to do less work per pedal stroke since we are doing that work at a higher rate. This goes back to the point about self-selecting cadence, you can put out the exact same power at a variety of different cadences, you simply are doing more or less work (pushing harder/less) per pedal stroke to maintain the same power.



Most people seem to arrive at a cadence that just feels 'right', but there are physiological differences between low and high cadence riding. Generally speaking, lower cadence relies more on musculature and high cadence riding is more cardiovascular. This is what Scott is alluding to with the target range of 85-95 RPM that is generally believed to be the 'right' cadence range for triathletes since we still have to run after riding, and tend to be more cardiovascular and less muscular than say a time trial specialist.



Of course, in practice, there are lots of exceptions to this and we see pros who grind massive gears at low cadence and then run 2:XX marathons, so this stuff is not exactly written in stone.

William Jenks

Technically, it's high cadence, low Torque.

(Torque is the angular analog of force, and you should think of them in the same way.)

tgarson

Technically, it's high angular velocity, low torque.

William Jenks

At least cadence is directly proportional to angular velocity using only fixed constants.... I'm close!