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Re: Scientists say high cadence is inefficient
Posted: 20 Feb 2019, 3:16pm
by Vorpal
Marcus Aurelius wrote:531colin wrote:Marcus Aurelius wrote:………. and high force high Cadence pedalling forces the muscles to feed mostly from fat, so a rider with a low body fat percentage can’t afford to do high force High cadence pedalling for very long, and that’s why the skinny pros do it the way they do it.
No. The body stores fat as energy source. Even "skinny" people have enough energy stored as fat so that they can survive for days without eating.
The body stores relatively little carbohydrate, as glycogen (a polysaccharide) in muscle and liver.
The article you linked compares 2 different ways of achieving the same power output.....
High cadence/low force
Low cadence/high force.
High force requires the muscles to metabolise carbohydrate. Glycogen stored within the muscle fibre is rapidly used up, and this means more muscle fibres must be recruited to maintain force, glycogen rapidly runs out and the muscle fatigues. More glycogen can be mobilised from the liver, and the liver can synthesise carbohydrate from fatty acids (gluconeogenesis) ....but not quickly enough.
At low force, muscle can metabolise fatty acids, and the supply is virtually limitless, although the ability to mobilise fatty acids benefits from some "training"....for example, exercising before breakfast.
So high cadence is better simply because it allows the rider to develop power without using high muscle force thereby conserving the energy supply.
No you’re wrong there.
Read this.
https://www.active.com/cycling/articles ... =pepperjamIt explains the what and why with numbers.
That seems like it says more or less what Colin said, only it specifies which type of muscle is using the glycogen.
Re: Scientists say high cadence is inefficient
Posted: 20 Feb 2019, 3:44pm
by Tigerbiten
Why bring up Chris Froome's data ??
The whole point of the initial article was that it's inefficient to ride at a high cadence in a low gear if you're not outputting enough watts.
When Chris Froome climbs a hill in a low gear with a high cadence, he's putting out enough power so that he's still at almost at peak efficiency.
That's how he's trained.
Joe average cyclist riding along the flat with a high cadence while in a low gear is nowhere near peak efficiency.
He just think he is because that's the dogma going around at this time.
Due to the loss of an arm on my bent trike my hill climbing is limited by how fast I overheat.
I very quickly worked out that I overheated faster if I tried to climb with a high cadence in a low gear vs a medium cadence in a slightly higher gear even though I was climbing at the same speed.
I'll admit I need more effort per pedal stroke which come down to how strong/fit your my legs where.
Ut because I wasn't overheating as quickly, I must have been more efficient.
YMMV .........
Re: Scientists say high cadence is inefficient
Posted: 21 Feb 2019, 12:57am
by Marcus Aurelius
Tigerbiten wrote:
The whole point of the initial article was that it's inefficient to ride at a high cadence in a low gear if you're not outputting enough watts.
Yes, I know.
Tigerbiten wrote:When Chris Froome climbs a hill in a low gear with a high cadence, he's putting out enough power so that he's still at almost at peak efficiency.
That's how he's trained.
Yes.
Tigerbiten wrote:
Joe average cyclist riding along the flat with a high cadence while in a low gear is nowhere near peak efficiency.
That’s right.
Tigerbiten wrote:He just think he is because that's the dogma going around at this time.
That’s right.
Re: Scientists say high cadence is inefficient
Posted: 21 Feb 2019, 1:09am
by Marcus Aurelius
Vorpal wrote:
That seems like it says more or less what Colin said, only it specifies which type of muscle is using the glycogen.
Yes and no. It also explains why anyone who thinks that high force, low cadence cycling will deplete fat reserves over Glycogen is wrong, and why exactly the opposite is true. ‘Conventional wisdom’ seemed to dictate that high force high Cadence cycling was a predominately Glycogen fuelled, it’s been proven that it isn’t, and why. The reason why low power high Cadence cycling isn’t efficient, is also encompassed. Running and cycling really don’t work the muscles in the same way, so they aren’t comparable enough to glean any useful information. It also explains why the often repeated “pedal at 90 rpms, its the most efficient way” isn’t quite right, you need to be making sufficient power at that 90 rpms to make it efficient, if you don’t, it’s not efficient at all.
Re: Scientists say high cadence is inefficient
Posted: 21 Feb 2019, 10:22am
by NATURAL ANKLING
Hi
Yes, high cadence low force is a waste of time and effort.
Only concentrate on high cadence if I wanna put a maximum power, which is normally only training on the turbo.
Fat burn, although they say that if you want to burn fat you need to stay around about 65% Of maximum heart rate, it is true that if you concentrate on high force which might include high cadence as well you will still burn fat.
Also are aerobic and anaerobic it’s not a line that you cross, it’s simply a transition of a mix of the two.
But at say 70% and 90% you are definitely more in one camp than the other.
Also it’s fair to mention that cadence is not simply cadence, It’s more to do with muscle dynamics, so with a peddling system that has different mechanics You’re comfortable cadence is likely to be different.
Has anyone any information on the burning fat in the Aerobic zone?
Re: Scientists say high cadence is inefficient
Posted: 22 Feb 2019, 5:50pm
by 531colin
Marcus Aurelius wrote:………. ‘Conventional wisdom’ seemed to dictate that high force high Cadence cycling was a predominately Glycogen fuelled, it’s been proven that it isn’t, and why. ..........
Please show me exactly where it says high force isn't down to glycolysis.
I have read and re-read
https://www.active.com/cycling/articles/why-fast-pedaling-makes-cyclists-more-efficient?cmp=39N-DP260-BND80-SD220-DM20-pepperjam&clickId=2489604936&publisherId=21181&source=pepperjam, and it says high force means glycolysis.
Re: Scientists say high cadence is inefficient
Posted: 22 Feb 2019, 6:55pm
by Boring_Username
So have I understood correctly?
- high cadence is efficient if I am going hard
- low cadence is better if I am going easy
But how do I know if I am going hard enough to raise my cadence?
Re: Scientists say high cadence is inefficient
Posted: 22 Feb 2019, 8:21pm
by Marcus Aurelius
Read it again. High force lower cadence = Glycogen. High force high Cadence = fat.
“However, athletes broke down the carbohydrate in their muscles at a greater rate when the 50 rpm strategy was used, while the 100 rpm cadence produced a greater reliance on fat”
Re: Scientists say high cadence is inefficient
Posted: 22 Feb 2019, 9:52pm
by Tigerbiten
Boring_Username wrote:So have I understood correctly?
- high cadence is efficient if I am going hard
- low cadence is better if I am going easy
But how do I know if I am going hard enough to raise my cadence?
You need to understand that the power band for each gear gets narrower as the gear size increases.
And the optimal cadence also increases slightly as the gear size increases.
So a low gear may have a power band of 60-80 rpm, while a high gear may only be 75-85 rpm.
Also efficiency wise it's better to sightly under-spin then over-spin.
So if you rigidly stick to a 85 rpm because that's what you've told is the correct cadence then it could well be right for high gears while you could well be over-spinning for low gears.
That what this article is about.
I work on how much pressure I put on the pedals.
If it starts to feel to easy then I'll climb a gear and if to hard I'll drop one.
I'll only increase the pressure on my feet if I run out of gears downwards.
If I'm doing it correctly I can keep the same feel all day even though my cadence can alter with speed.
YMMV .........
Re: Scientists say high cadence is inefficient
Posted: 22 Feb 2019, 10:02pm
by 531colin
Marcus Aurelius wrote:
Read it again. High force lower cadence = Glycogen. High force high Cadence = fat.
“However, athletes broke down the carbohydrate in their muscles at a greater rate when the 50 rpm strategy was used, while the 100 rpm cadence produced a greater reliance on fat”
Look at the context. immediately above your quote.....
"In one case the cyclists pedalled their bikes at 50 revolutions per minute (rpm) while using a high gear. In the second case, the athletes pedalled in a low gear at 100 rpm. The athletes were traveling at identical speeds in the two instances, so their leg-muscle contractions were quite forceful at 50 rpm and moderate -but more frequent- at 100rpm.
As it turned out, the athletes' oxygen consumption rates were nearly identical in the two cases, and heart and breathing rates, total rate of power production, and blood lactate levels were also similar."
So 50 rpm is "quite forceful" and 100rpm is "moderate" contraction force.
50 rpm ...."forceful" contraction = glycolysis
100rpm ..."moderate" contraction = fatty acid breakdown
The article doesn't consider high cadence/high force at all.
Re: Scientists say high cadence is inefficient
Posted: 23 Feb 2019, 7:20am
by Boring_Username
Tigerbiten wrote:I work on how much pressure I put on the pedals.
If it starts to feel to easy then I'll climb a gear and if to hard I'll drop one.
This is what I did before I heard about the science...
Re: Scientists say high cadence is inefficient
Posted: 3 Mar 2019, 8:03pm
by david7591
“So why do newbies try spinning in a low gear when it is isn’t worth it? Formenti has a theory. “They might presume that the smoother blood flow at a higher cadence keeps the exercising muscle well oxygenated.”
They may do, but they may just find it easier spin a low gear
Re: Scientists say high cadence is inefficient
Posted: 3 Mar 2019, 8:05pm
by david7591
Good point in the article about not pedalling like Chris Froome. After all he’s soooooo inefficient!
Re: Scientists say high cadence is inefficient
Posted: 4 Mar 2019, 3:27pm
by Vorpal
I'm not sure that we are all talking about the same things, here.
Form the link in first post, despite the silliness about not imitating Chris Froome...
For riders with experience this is not a problem because they tend to change up through the gears until comfortable with the higher intensity of exercise at their preferred cadence.
But novices and recreational cyclists sometimes stay in a low gear and spin quickly, even though the overall intensity of their exercise is relatively moderate.
I'm pretty sure that my 'spinning' is reasonably efficient. But if I am averaging 15 or 16 mph on a hilly 40 miles ride and my 'normal' cadence is about 80 rpm (it does slow a bit on hills) it's a bit different to someone going 8 mph at 100 rpm, which I think is more what the article is talking about.
In my experience, new and returning cyclists are much more likely to be pushing too big a gear, rather than too small. The bikes sold to recreational cyclists are often over geared. Though, that's another problem, it's not likely to lead to new cyclists spinning inefficiently. The group of folks who are ineffcient because they are spinning too fast for the exercise they are doing is probably pretty small, and limited to recreational cyclists who spin because they've heard that's more efficient.
Re: Scientists say high cadence is inefficient
Posted: 4 Mar 2019, 3:54pm
by geocycle
Boring_Username wrote:So have I understood correctly?
- high cadence is efficient if I am going hard
- low cadence is better if I am going easy
But how do I know if I am going hard enough to raise my cadence?
I think you are right and the answers are all relative. My high and your high will probably be different, and certainly different from Mr Froome.
One other point. My experience is that using a high for me cadence and low gear (again for me) puts less pressure on my knees such that I ache less next day. So, as well as cardiovascular exertions we might need to think about structural issues? Or should I just put up with the pain of grinding a high gear because my muscles will get stronger??