The Cadence Conversations

LarryOz

Cruzeum Curator & Sigma Wrangler
Do you think that the crank length has an effect on the natural cadence as when I went from 175 mm to 153 mm, my natural cadence, on the flat, went from 80 up to 92, with the same power, AND the same pressure on the pedals.
Good point Slim, Yes I totally forgot to bring the short cranks into the discussion - how silly of me. :rolleyes:
Think about it - the shorter your cranks are the "less" distance your legs have to move with each rotation. That is a lot of mass that you have to move less distance, therefore saving energy. You can spin quicker, and spin up to speed quicker with shorter cranks. Like everything else, at some point of shortness <90-100mm, other factors start coming into play, but many people have tested crank lengths on both bents and DF's and have come to the conclusion that there is no power loss when going to shorter cranks.
I am not sure if the crank length to power requirement is linear, although I believe it is: but you are correct when you say same power and same pressure on the pedals with increased cadence from 80 to 92. Reducing crank length from 175 to 153 = 12.5% decrease. This 12.5% reduction in length would require an addition 12.5% power with each pedal stroke since the moment arm is shorter - but since cadence went up from 80 to 92 (13% increase), this in effected cancelled out the increased demand of power per stoke. win, win
 

Osiris

Zen MBB Master
What is the crank length of the stock FSA crankset on my V20? I can't see it indicated anywhere. My other bents use 165 mm cranks. Maybe that's why I can pedal them at a faster cadence?
 

jond

Zen MBB Master
Ratz you nailed it.

I too on trainer have a higher cadence than on road. I put that down to variability of the road.

And yes as I start to tire the cadence ....heck everything slips. To a self selected 70 75.

I use 172.5 and 175 mm cranks. I think shorter cranks on the flat would be good for me at 187cm.

I reckon higher cadence has obvious advantages as you duly note and it is worth pursuing for the form gains alone.

But as you lose that form and start to fatigue increased cadence leaves you more prone to cramping. We all pedal slower before that cramp onset.

I note most of us during a century see a 10 15 rpm cadence decrease over course of ride.
 

DavidCH

In thought; expanding the paradigm of traversity
Here's an interesting video about sustaining 440watts for an hour. It can be done.

 

LarryOz

Cruzeum Curator & Sigma Wrangler
Here's an interesting video about sustaining 440watts for an hour. It can be done
That was an interesting video to say the lease.. :eek:
I agree in the pedal cadence, foot angle on the pedal for his position, and also that much of the fight is in the mind when you are maxed out. He did however seem to imply that this 440 watt effort could be possible for many other people. I beg to differ with that comment. Some people are just stronger than others. Some of it slowly starts going away as we age. Wiggins is only 37 - so still in prime. (Unlike me at 58!) Yikes - He is also 6'2"and weight more than me at 152 lbs. No wonder so fast. It would be neat to see how fast he could go on a Vendetta! :cruzbike::cruzbike::cruzbike::cruzbike::cruzbike::cruzbike::cruzbike::cruzbike: (Send him one Jim and see what he does with it!)
You still have to know what you top end is, your Lactate Threshold (LT) - If you ride much above that for a sustained period you cannot go on.
I think we could all learn to suffer harder and push ourselves, but that is also a skill not too many people like to learn. Pain is pain, and you need a high motivation level to be able to learn to endure the pain, first in the solitude of training, then in the big event.
 
That was an interesting video to say the lease.. :eek:
I agree in the pedal cadence, foot angle on the pedal for his position, and also that much of the fight is in the mind when you are maxed out. He did however seem to imply that this 440 watt effort could be possible for many other people. I beg to differ with that comment. Some people are just stronger than others. Some of it slowly starts going away as we age. Wiggins is only 37 - so still in prime. (Unlike me at 58!) Yikes - He is also 6'2"and weight more than me at 152 lbs. No wonder so fast. It would be neat to see how fast he could go on a Vendetta! :cruzbike::cruzbike::cruzbike::cruzbike::cruzbike::cruzbike::cruzbike::cruzbike: (Send him one Jim and see what he does with it!)
You still have to know what you top end is, your Lactate Threshold (LT) - If you ride much above that for a sustained period you cannot go on.
I think we could all learn to suffer harder and push ourselves, but that is also a skill not too many people like to learn. Pain is pain, and you need a high motivation level to be able to learn to endure the pain, first in the solitude of training, then in the big event.
I completely agree @LarryOz I wish I could train that hard (even when my training regime is not interupted by lack of time and sleep deprivation). I have a natural aversion to pain and I just can't motivate myself to go on unless I am seeing results i.e. if I am going fast with a tail wind I will continue to do so and push myself harder; however if I am fighting a head wind and feel that all this effort is getting me nowhere I get demorialised and decide to take it easy. I did have a minor win riding into a headwind on last nights ride but the ride out sleep deprivation and exhaustion was my demon.
 

Osiris

Zen MBB Master
however if I am fighting a head wind and feel that all this effort is getting me nowhere I get demorialised and decide to take it easy.

I used to suffer from that demoralizing effect as well, but since I've been using a power meter, I forget about speed when encountering a headwind and just turn my attention to how much power I'm putting out. Now I can enjoy even steep hill climbs, which I used to loathe.
 

bladderhead

Zen MBB Master
LarryOz said:
I think we could all learn to suffer harder and push ourselves
I do not think I will ever get anywhere near the pain threshold. In order to do so I have to go through the breathlessness threshold, which I seem to reach really easily. My lungs are my power meter. I like to keep my effort constant. Would it be better training to sprint unto the point of heart failure and then slow down?
 

LarryOz

Cruzeum Curator & Sigma Wrangler
I do not think I will ever get anywhere near the pain threshold. In order to do so I have to go through the breathlessness threshold, which I seem to reach really easily. My lungs are my power meter. I like to keep my effort constant. Would it be better training to sprint unto the point of heart failure and then slow down?
The key is to find that spot "just before heart failure" and then back off 1%, it is amazing how long you can stay at that level - especially if you imagine a black bear is chasing you or something.
 

super slim

Zen MBB Master
The key is to find that spot "just before heart failure" and then back off 1%, it is amazing how long you can stay at that level - especially if you imagine a black bear is chasing you or something.
OR carry a portable battery powered heart defibrillator, AND ride with someone who knows how to use it!!!
 

LarryOz

Cruzeum Curator & Sigma Wrangler
Maybe I will be as fast as Larry when I reach Larry's age. Maybe I will never reach Larry's age, and the bear will get some self-slaughtered meat.
It is just that we tend to get faster as we get older. I do not know why - but that is just the way it works for some reason. I can't wait to see how fast Jason is when he is my age. Of course then I will be 90 - and gosh, by then I should really be fast. :rolleyes::rolleyes::eek:
 

Bill K

Guru
It is just that we tend to get faster as we get older.
In my case (65) it seems like the brain slows down instead of the bike speeding up.
At least it feels faster so the fun factor is preserved:)
Or maybe I just need more time on the trainer...

OR carry a portable battery powered heart defibrillator
That might make an effective training aid: If your heart rate gets too low, you get zapped.
Pedal harder... or else!
 

Rod Butler

Well-Known Member
I do not think I will ever get anywhere near the pain threshold. In order to do so I have to go through the breathlessness threshold, which I seem to reach really easily. My lungs are my power meter. I like to keep my effort constant. Would it be better training to sprint unto the point of heart failure and then slow down?

"My lungs are my power meter..." profound! Always have been, always will be. You can't burn fuel without oxygen.
Strengthening the muscles involved in breathing (intercostals & obliques as well as Lats and the diaphragm)
will always pay better time/effort dividends, especially as we all age, in so very many aspects of our lives.
Try taping your mouth shut when you ride, then slow down until you reach a steady manageable pace.
This is where the strengthening process begins, in yoga this is pranayama (sans taping...!) Nameste
 

DavidCH

In thought; expanding the paradigm of traversity
The key is to find that spot "just before heart failure" and then back off 1%, it is amazing how long you can stay at that level - especially if you imagine a black bear is chasing you or something.
Three great big wild dogs with gnashing teeth at 7 in the morning does it for me.
 
Coming late to this, with no power meter data to throw in here, I tend to use HR as the proxy for power/effort/lactate, having used HR based training for years. I do notice that as I fatigue my cadence tends to drop, the key is to notice it and change gear. Last time I went out on the M5 I deliberately went in the 34T ring all the way to avoid the low cadence bad habit. I ended up higher up the block (smaller cog) but the same average speed.

I'd wholly agree with the idea that recovery must be recovery (I think that's in another thread) and I use the turbo trainer to allow me to train at high cadence (90+) and low HR (<140) for those recovery sessions. Seems to be working overall for my target ride type which is audax, I'm normally home at the head of the field.

As for crank length I took a look here http://www.recumbents.com/wisil/misc/crank_angle.asp. For my data it came back with interesting results.

For a medium BB - 150 - 155mm cranks, which is what I have on my M5 M-Racer - recline angle nearer a Vendetta and BB at nose height .
For a low BB - 165mm cranks. For my Silvio I'm building that with an Ultegra triple with 170mm, and seems to have less than half of the height difference between BB and seat
So those would seem to be about right, although the article is not clear what constitutes H/M/L BB
 
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