cyclezen

Finally got a nice working HRM yesterday - been without one since mid-90's and forgot how AB FAB they really are!

Anyway along with a bunch of info from yesterday's ride, there's this, which I'd like to get BFer's interpretations on:

while steady tempo riding, middle of ride so already well warmed up, on a flat section, positioned on the hoods:

riding in a 79 inch gear - 100-105 rpm - reading 23.6 to 24 mph - my heart rate was steady 140-142

same section, now riding in a 91 inch gear - 85-90 rpm - also reading 23.7 - 24 mph - heart rate was 150-154

How would you interpret this...

lillypad

Your muscles are becoming oxygen-deprived and your heart is working harder trying to get more and more oxygenated blood to the muscle cells.

fuzzthebee

You came upon a slight headwind?

cyclezen

good comment, but I guess I wasn't clear enough
this is not a trick question. If I didn't note it, the conditions were same,same.
sections were back to back and not putting me anerobic.
and, btw, there was no real headwind, just a gentle breeze plus the 'apparent wind' from movement.

what I mean is the fact that one gear/cadence vs another gear/cadence, with both at the same road speed, showed a difference in heart rate - meaning one actually caused me to do more 'work' than the other.
ideally, everything else being equal - both should show the same heart rate...???? (my other expectation was that the higher cadence might show a higher heartrate, even if only minimally so - it didn't...)
What I'm trying to come to is what the 'difference' implies relative to my current state of conditioning.
This is telling me something and should be pointing me in a direction for further training. I'm just not sure what its telling me, and someone else might 'read' this differently than I do.
So I'm really anxious to hear any and all thoughts.

socalrider

Simple explanation would be that your body is more efficient when spinning a smaller gear rather than grinding a bigger one..

The data shows that fact if all conditions are the same...

cyclezen

that was initially my conclusion also, but
85-90 isn;t really 'grinding', although 91 is big, its not really that big...
and 15 years ago at 40-41, moving a 90 inch gear was 'easier' than twiddling a lower gear at the equivalent road speed. (my comparo cause I have some HRM data from back then... but not younger).
Is this a 'muscle strength' V 'aerobic capacity' thing, maybe? age-related?
if so, is it telling me what I need to focus on for the coming pre-season months?

WarrenG

First interval was the warm-up, second was after you were warmed up. Your HR will generally be able to go higher (and do more work for you) once you are fully warmed up. You might try repeating your test by doing the lower rpm's first.

It's possible that your natural cadence is the higher one and that's fine. Forces at the lower cadence are _slightly_ higher so this may indicate a weak area for you but I think the mechanical efficiency you have developed at the higher cadence is simply better. Probably best to stick with 95-100 rpm's and worry about other things that matter more.

socalrider

I am now 40 and find that holding a higher cadence, right in the 100 rpm is ideal for me.. When I was racing and much younger that would easily of been 10-15 rpm's less..