Riding non-stop

[Mick F]

I've just got back from a 43mile ride and I didn't stop once. Average moving speed 13.5mph, active time of 3hrs 10mins.

Question:
By riding non-stop, do I consume more of my flab than if I'd stopped a few times to admire the view?
(granted that the active time and average moving speed would be the same)

ie do I burn more calories by keeping going?

[swansonj]

As a general rule of physics: for a strictly linear system, it matters not: half an hour at 150 W followed by half an hour's break is the same as an hour at 75 W. But nothing in life is ever linear, and bicycles and bicyclists are certainly not. Wind resistance increases faster than linear, and assuming you achieve a higher speed in part by pushing harder rather than spinning quicker, I think that is non-linear too. In the presence of non-linearities, the lowest-energy solution is always the one with least variation.

So I suggest that for a given average speed over a given distance, the lowest energy consumtion will come from doing it as uniformly as possible. Doing part of it quicker then stopping will, I suggest, take more energy. (Whether "as uniformly as possible" means uniform speed or uniform power output, or put another way, what is the optimum balance between those two, will depend on how much of your energy is expended on the road and how much in wasted heat in your muscles.)

Of course, I've made the naive physicist's assumption that energy used = weight lost - any physiologists out there are welcome to explain why that may not be true...

[meic]

I have heard that your body continues to metabolise at an increased rate for around 20 minutes after you finish exercising, so I imagine that a few breaks like that may increase the overall burning of fat.
Unless it is exactly that time needed at the re-start before metabolism recommences.

[Mick F]

swansonj
Sorry, perhaps I wasn't clear.
I mean that if I'd stopped, I'd have had the same "active" time and the same "active" average speed as if I did it non-stop.

ie 3hrs non-stop at 13.5mph - or - 4hrs with two half hour breaks but still do an "active" 13.5mph average.
Active average speed NOT average speed.

[RickH]

With the breaks it is possible that you are consuming slightly more calories by having a couple of breaks.

Of course if you are also in a teashop consuming cake during the breaks then that will tip the balance the other way!

Rick.

[Paul-S]

ie do I burn more calories by keeping going?

In the short term, probably not. But do it often enough on regular basis and you probably will.

Cheers,

Paul.

[531colin]

You would use more "food" if you pushed your body into a less efficient metabolism.....
But I can't remember if for example anaerobic is less efficient than aerobic?
I think having a break will enable your muscles to get back to an aerobic condition, but pushing on you would be in oxygen debt for more of the time?
"Feeling the burn" means oxygen debt, I think....havn't thought about this for a very long time!!

[hubgearfreak]

ie do I burn more calories by keeping going?

no. stopping consumes kinetic energy which is evident by the heat in the brakes/rims. to start off again requires muscle.

go and do the same ride, but this time stop every time you get up to speed if you doubt it.

[Mick F]

Now that's an argument I can handle!
Take an argument to extreme and you show all the foibles!
Yes, ride for a minute and stop. Repeat all day. Knackering!

However, not taken to extreme, would I have used more fat and flab by stopping a couple of times in the 40odd miles? Just to relax and let my HR fall.

[tatanab]

You would use more "food" if you pushed your body into a less efficient metabolism

On a Sunday I usually go for about 25 to 30 miles before breakfast, just a cup of tea and then go out. I remember reading that this is good for fat burning. I often do this on tour because if camping I like to be on the road by 7am so ride for an hour or two before stopping for food.

[vjosullivan]

Resting allows the lactic acid build-up in your muscles to disperse. But that's neither here nor there. If you're not stopping from time to time to admire the view, you might as well just buy a static trainer and stay at home.

[karlt]

You would use more "food" if you pushed your body into a less efficient metabolism

On a Sunday I usually go for about 25 to 30 miles before breakfast, just a cup of tea and then go out. I remember reading that this is good for fat burning. I often do this on tour because if camping I like to be on the road by 7am so ride for an hour or two before stopping for food.

I'd be looking to top mesen through low blood sugar if I tried to do that!

[swansonj]

swansonj
Sorry, perhaps I wasn't clear.
I mean that if I'd stopped, I'd have had the same "active" time and the same "active" average speed as if I did it non-stop.

ie 3hrs non-stop at 13.5mph - or - 4hrs with two half hour breaks but still do an "active" 13.5mph average.
Active average speed NOT average speed.

Yes, sorry, I didn't pick up the significance of "moving average" and "active cycle". I always start my cycle computer at the start of each day and stop it when finishing for the day (or start and finish of each leg of the commute), so I think in terms of the average speed averaged over all stops, lunchbreaks, traffic lights etc. I think that's more reflective of fitness level than recording a higher average over a series of short spurts with long breaks between to recuperate.

[531colin]

You would use more "food" if you pushed your body into a less efficient metabolism

On a Sunday I usually go for about 25 to 30 miles before breakfast, just a cup of tea and then go out. I remember reading that this is good for fat burning. I often do this on tour because if camping I like to be on the road by 7am so ride for an hour or two before stopping for food.

I'd be looking to top mesen through low blood sugar if I tried to do that!

Riding on "empty", eg before breakfast, is a good way to "train" your body to metabolise fat as an energy source (as fatty acid). If you never ride on empty, you will need to be constantly snacking to maintain a work rate.(If you are looking to maintain a high work rate (racing, audax) you will need to snack anyway.)
For the same exercise, and the same eat, it makes no difference to any weight loss if you exercise then eat, or eat then exercise.....when its all over, its simply a case of X amount in, Y amount out.

Normal diurnal rhythm establishes a "normal" blood sugar before your normal wake-up time. Anybody who has done night-time call-out, or had kids who wake up in the night will be familiar with that desperate sick/cold/giddy/legs like pipe-cleaners feeling when you are jolted from deep sleep in the wee small hours.....thats low blood sugar, when your body is absolutely convinced it should be asleep.

[Ayesha]

Look at it as kCals/mile + the climbing.

An average touring bike with the average bloke on it gets through about 50 kcals/mile.
For the climbing, 4.2 Joules is 1 Cal.
kg weight x g x metres climbed = J. Devide this by 4200 and that's roughly the kCals added for climbing.

Take a slow ride with no stops or a fast ride with a stop, and its roughly the same calorie burn.

The difference is the intensity while riding. Do the cycling at close to your VO2 max and you'll use more carbs. Do the cycling as gently as possible and you'll metabolise fat for energy.
If you chose the former, the physiology keeps your heart beating and blood pumping to 1/ flush out lactic acid, 2/ cool your muscle tissue and 3/ expell H2O from the energy process.

PS Colin. I didn't know Audax was "high work rate" , and yes, one can train to be ketogenic.