For the larger effect, I agree that more fit people can consume more calories and produce more power.

But higher efficiency motor is the right analogy for the question I'm asking. As I've said, I've been told that more fit people can do the same activity using less calories. Meaning that their muscles are more efficient. In workout circles, there are a lot of trainers who tell you to mix it up because of this. That clearly doesn't make it true.

I still maintain that we need to find somebody for whom this falls into his/her field of study to answer the question.

It would be helpful to have an expert to chime in.

The basic of the biochemical reaction for energy conversion and muscle contraction have been worked out in fairly details already. Is there something you see that might suggest otherwise? One area there is a definite increase efficiency is neuromusclar coordination where the muscle fibers recruitment is synchronized during the contraction. But this doesn't take long for the body to learn. For example, if you never do weightlifting, within the first week or two, you'll see an increase in weight you can lift and that's strictly due to neuromuscular coordination improvement.

I didn't see this before and I don't mean to be rude and call you out, but being exact is kind of the point of science.

https://en.wikipedia.org/wiki/Scientific_method

Trying to be exact, which is not the same as being exact. But for BF purpose, I say it's close enough.

Being exact, getting the right answer, is the goal of science. But along the way one of the basic tools by which science advances is by acknowledging that the goal has not yet been reached and by trying to indicate how far off the goal one might be. Measurements in science always include an estimate of the likely measurement error. A lot of effort goes into analyzing errors or possible errors.

In physics where the systems are relatively simple, the errors can be understood and reduced more easily than with very complex systems like mammals, e.g. humans. With mice they have developed strains that are genetically identical which cuts out one source of variability. With humans there are also ethical issues that make the science even harder.

Ha, I didn't mean to start a philosophy type discussion.

Was just trying to say...scientists are taking their hypothesis and testing the hell out of it...most likely a lot more than ramblings by non scientists on a bike forum.

Er, no. One can use the scientific method to arrive at approximations. It is perfectly scientific to assert that X appears to be true within a given margin of error, and subject to y. Besides, physics is a science which has given us the uncertainty principle, and Godel's incompleteness theorem has shown that even mathematics cannot be shown to be both complete and internally consistent.

cplager, I sympathise but am still sceptical of your position. We mix it up in training because specific training produces very specific muscular (including neuromuscular) and metabolic adaptations, and we typically want a range or combination of those adaptations. And it may well be that the fit athlete finds it "easier" to lift a given weight or propel a bike not merely because they are aerobically fitter or stronger but because they recruit more muscles, or different types of muscle fibre, to the task. But finding it easier in this sense wouldn't equate to burning fewer calories. The power required for the task doesn't change, it is merely being deployed differently.

I'm prepared to accept that some people will be more efficient than others at converting their food energy into power output, though I suspect the differences will be small. And it isn't altogether clear to me what difference we would expect physical training to make to that process. After all, for most human activities the availability of fuel isn't the limiting factor - we can run along for days and days, at moderate intensities, on pretty small amounts of fat - and most of our food goes to maintaining our body temperature, rather than moving us around. Evolution-wise, I'd have thought the pressure to become more efficient at conserving energy would come not from a need to sustain higher levels of activity, but to withstand longer periods without food - hence hibernation, and the hummingbird's ability to slow its metabolism dramatically overnight. But as always, I could be wrong.

Hi,

If I didn't agree with me before, I don't think I'd agree with me now either on this one. :D

I'll repeat the snippet I posted earlier. It sounds plausible, but could be completely full of you-know-what.

From some random post on the internet:

And even if it is true, it answers (somewhat) "how" but not "how much".

Cheers,
Charles

Yeah, I have read, e.g. in Good Calories, Bad Calories, that this is why it just doesn't work to try to lose weight by radically restricting caloric intake. Your body can go into famine mode and just shut down and burn very few calories.

I think you are just confused. chasm54, sreten and others provide very good information. And there is nothing philosphical about scientic method. Its results can be but not the method itself.

See this paragraph:
Call me crazy, but I'm much more likely to believe a scientific theory until it's proven false than to believe a claim stated on the internet.

Needless to say, I took a comment out of context and made it more out of context. Just disregard and move on.

Hi,

No doubt an unfit person will become more effective at riding a bike as
they get used to it and their nervous system sorts out where, when
and how much for each muscle through the pedal stroke.

Some may say you become more efficient on the bike, but you don't,
you become more proficient using what muscles you have effectively.
The net result is not drop in calories, it is more power output, you
go faster and end up burning more calories as you improve.

I've no truck with the idea efficiency (calories used / power output)
improves significantly with exercise, with no suggested mechanism
other than some people think it does just because it possibly could.

That is a very unscientific opinion, and in the end it doesn't matter,
even if it did it would affect say your first month and be irrelevant
after that, extra calories burnt will = the work done, which =
the integral of power output over the time period ~.

~ Because involving the two types of fast twitch muscles, both
do anaerobic, one can also do aerobic as well, in some parts of
ride will increase the calories used, but not much overall.

Basically going faster over a given distance will burn more calories,
and for most people that is all they need to know. After six months
doing a distance in the same time you did after 2 months may feel
a lot easier, but the calories used up will be very near the same.
But you won't be doing that, you'll be just doing it faster.

rgds, sreten.

FWIW all space missions completely ignore Relativity. Newtonian
physics is exact enough for the circumstances, but Relativity
showed that Newtonian physics is hopelessly wrong under
certain circumstances and is never exactly exact.

Science is the best theory to use, not the truth.

Hi,

It doesn't answer how at all, nevermind how much.

More mitochondria increases power output, so does
more cells, bigger cells, better blood supply etc, etc.

The comment on efficiency is completely trite and meaningless.

Even though it pretty much has to be true if the resting metabolism
% higher of well developed muscle is nowhere near as much higher
than the extra % higher power output it can output over unfit muscle.

If you disregard static energy requirements you have no mechanism
for extra efficiency. I walk and (occasionally run) everywhere. The idea
my leg muscles could be an extra 10 to 20% efficient but they can't
be bothered unless stressed just doesn't fly, it makes no sense.

rgds, sreten.

First, that's not what was said. Second, given your level of expertise here, how much weight are we supposed to give your opinion just because it doesn't make sense to you?

Again, debating this without "proper adult supervision" is pretty much meaningless. If we want an answer, we need to find somebody who can answer the question. Having the same uninformed individuals argue for one side or the other isn't furthering our understanding here.

Hi,

Its pretty clear who round here overrates their own musings.

Trite "Your not an expert so you don't know" to any viewpoint
or opinion that doesn't suit you is toys out of the pram stuff.

Your uninformed, don't for a second assume so is everybody else.

Its you that in indulging in a pointless circular defense of your opinions.

Getting the right answer is asking the right questions, not insisting
a question is valid and needs an expert, no-one here, to answer it.

rgds, sreten.

I'm sorry. What are your qualifications on this topic? While I don't know what you do for a living, it seems pretty clear from your postings that it isn't as a scientist*.

I very clearly stated that (1) what I had was an opinion (that may not be correct) and (2) that I wasn't qualified to answer the question we wanted answering. I'm curious as how you see that as "overrating (my) own musings." And pray tell, how does you spouting uninformed comments after badly parsing what was reading advance us to our goal to answering this (actually interesting) question?

When it comes to the physics of bicycles, I am often qualified to respond as an expert. When it comes to the biology and biomechanics, I am not. You, on the other hand are posting basically anonymously on a bike forum with, well, a spotty record at best (would you like a review of the many posts you started that just went, well, badly?). Not to mention a quite mixed record as far as helpfulness or correctness of many of the opinions you've posted in the past (and by mixed, I really do mean mixed as some of your comments have been quite helpful and some have been dreadfully incorrect).

Getting the right answer isn't only asking the right questions. Forming a "consensus" in this forum on what the right answer is does nothing to making sure we have the correct answer, unless we make sure we involve the right people (which I know for this question isn't me and you seem hell-bent on demonstrating it's not you either). There is a best answer to this question out there, but honestly, what have you done to get us closer to it?

* Just to be clear, one does not need to be working as a scientist, nor even formally trained as one to be able to contribute usefully to these conversations. But your postings about science seem to indicate a significant misunderstanding about what science is and how it should be used.

I average 12mph for about 360 minutes (6 hours) a week. Casual riding for fun and fitness. I eat normal meals 3 times a day. and every Thursday on the dot I lose 1 pound. Ive lost 16 pounds in 16 weeks since I got my bike. This even includes eating fatty foods like McDonalds.

I don't count calories burned, your in your 20's and should know your body. You should naturally feel when you are bettering your body compared to when you are not. eat normal and ride! 1 pound a week adds up dont even worry about counting calories burned. You know when you had a good day.

Hi,

Disappearing up your own circular arguments is a skill I've never managed.

You think I'm not a scientist ? Your being a pompous idiot, who cares what you think ?
Which is basically to denigrate stuff you know nothing about on the phenomenally
stupid basis it must make some sense to you in some way or it must be wrong.

Such tedium adds nothing to threads. Personal comments are the pits, pathetic.

rgds, sreten.

Personally I'd say there is about an order of magnitude difference in
the understanding of science here, and hence the pointless nonsense.

You only need very basic physics to nearly fully understand bikes.

I got an odometer for my bike two years ago and now it reads 6300 miles. I average about 10 mph but it's pretty hilly around here. 30 feet of climbing per mile is typical. My BMI is pretty much stuck at 25, i.e. my weight has not changed significantly in 2 years.

Just another data point.