Peter Hitchens on cycling and weight loss

[Sweep]

It’s worth being very wary of the “men need 2500kcal each day” thing too.

Just out of curiosity, I monitored my calorie burn on ‘non cycling’ days by using a Fitbit watch for a while, and assuming it to be accurate if demonstrated that c2500kcal amounts to a pretty busy/active day. When I was working full time and commuting I did get through that, like wise of at home on a busy day, or on a day out, but have an easy day, go to the cinema, spend s couple of hours driving somewhere and ….. far less energy burned. I reckon an easy day only uses 1500-1800.

a lot of truth in this I think.
The good news is that I think just sitting around maintaining the basics of daily life'keeping the body ticking over uses a fair chunk of calories - hence the effectiveness of tight calorie control.

[axel_knutt]

I think it is generally known and agreed that you cannot work/cycle weight off. AIUI, those people in the past who did manual jobs were thin because food was scarce and expensive.

"Analysis of the mid-Victorian period in the U.K. reveals that....their levels of physical activity and hence calorific intakes were approximately twice ours."

"Due to the high levels of physical activity routinely undertaken by the Victorian working classes, calorific requirements ranged between 150 and 200% of today’s historically low values....calorific expenditure ranges during the working week of between 3,000 to 4,500 calories /day (men) and 2,750 to 3,500 (women)."

"At the top end of the physical activity range were the ‘navigators’, the labourers who built (largely without machinery) the roads and railways that enabled the expansion of the British economy. These men were expending 5,000 calories or more per day."

"In short, the mid-Victorians ate twice as much as we do, but due to their high levels of physical activity remained slim"

Clayton & Rowbotham
How the Mid-Victorians Worked, Ate and Died
International Journal of Environmental Research and Public Health

Probably running burns slightly more calories per hour, but otoh you can cycle all day much easier than you can run.

Have a look at the ACSM Compendium of Physical Activities I linked above, it lists the energy consumption for just about every conceivable activity: walking, cycling, running, washing the pots, having sex........

I have cycled every day for 1-2 hours and not seen in any weight loss, and also cycled much less and lost weight. latter due to lack of food, former while eating lots of it

Firstly, an hours exercise would use ~400kcal, and the calorific value of bodyfat is 7800 kcal/kg, so that's about 50g of fat. That's far too small to measure over the course of one day, because the confounding variables affecting your weight are far bigger than what you're trying to measure. Hydration, stomach contents, bowel contents, and bladder contents can all contribute to a weight change of a kilogram or more.

The point is that weight change due to fat loss is small in the short term, but cumulative over the long run if exercise is sustained, whereas weight change due to the confounding variables is large over the short term, but it's non-cumulative because if your bladder goes from full to empty on consecutive days it can't be twice as empty a day later for example. This means that over a long enough time period, your average weight change due to confounding variables gets closer and closer to zero.

The secret to getting accurate measurements of your metabolic rate is to keep records of your calorie intake, exercise hours, and weight every day for months and months, preferably years. I've been doing it for 20 years, and you can see from my results plotted above that there are still quite substantial confounding variations around the underlying trend.

It also helps if you understand how to get the best weight measurement accuracy. You need to weigh naked first thing in the morning, after you've been to the loo, and before you eat. Bathroom scales are cheap consumer products not lab instruments, they give a different reading as you shift your weight left-right, forward-backward, so you need to practice the art of distributing your weight evenly and reliably. As you get different readings each time you step on them, you also need to step on the scale multiple times and average the readings. When you come to calculate metabolic rate, you need to do it over periods of at least three months, and the weights you use at the beginning and end of those periods need to be the averages of about 7 consecutive days.

Lastly, you could burn 2500kcal on a non-exercise day, and say 2900kcal on a day with an hours exercise, and if you do that on alternate days your overall average calorie use would be 2700/day, so if you eat that each day your weight will be maintained. However, the fact that you're eating the same calories each day doesn't alter the fact that if you were to cease exercise your consumption would fall to 2500/day.

[Jdsk]

I'm sure there's a simple correlation between the efficiency of the cycle as a machine and the way that weight loss might be achieved. In fact, I'd venture to suggest that it involves just fairly straightforward sums.

Unfortunately not. For a wide range of different reasons, including:

1 Metabolic rate isn't constant even at a given level of exertion. And we're only just getting an inkling of how it's regulated.

2 Calorific intake isn't easy to measure. We don't fully oxidise everything in the way that a bomb calorimeter does.

3 Because of the massive energy storage density of fat and the long periods of time that are of interest the input data would have to be very precise. (As you and others have described above.)

Jonathan

[axel_knutt]

It’s worth being very wary of the “men need 2500kcal each day” thing too.

The figure of 2500kcal/day was based on self-reported data, which is notoriously unreliable because people lie about what they eat and how much exercise they do, and fat people lie more.

The accepted gold standard for measuring metabolic rate is the doubly labelled water method, using that, the correct figure is nearer 2900kcal/day.

http://38r8om2xjhhl25mw24492dir.wpengin ... -Final.pdf

[axel_knutt]

The escape from this vicious cycle is exercise that demonstrates to your body that you need all the energy that its metabolising so that it won't be tempted to reduce metabolic rate, but it needs to be short duration, medium-high intensity, low intensity exercise just doesn't seem to curb the body's drive to save energy. Since my health has prevented me from doing anything but very low intensity exercise over the last 10 years, I've struggled to avoid weight gain, and gone up from 69kg to 79kg.

Spot the difference between exercising before I developed AF when my typical exercising HR was 115-125bpm, and exercise post AF, when I've had to actively avoid getting my HR above 85-90bpm:

If you want to lose weight, gentle exercise just doesn't cut the mustard, although I'd be willing to bet that the definition of gentle will be by reference to each individual's own personal activity history, and not simply a fixed fraction of MHR.

[thelawnet]

Probably running burns slightly more calories per hour, but otoh you can cycle all day much easier than you can run.

Have a look at the ACSM Compendium of Physical Activities I linked above, it lists the energy consumption for just about every conceivable activity: walking, cycling, running, washing the pots, having sex........

kcal per mile temp.png

This graph is rather unhelpful to the topic of exercise.

One exercises for an hour, or two hours, or whatever, not for a certain number of miles. Doing an hour at 20mph will burn hugely more calories than at 10mph, but this graph does not show that very well.

[horizon]

I've linked to Dr Yeo before, thanks to someone else posting the original link. I like what he says. AIUI, it's not how much you eat (i.e.calories) but what you eat (i.e. how available those calories are)

https://www.youtube.com/watch?v=GQJ0Z0DRumg.

[Pebble]

I think the body is just programmed to desire at least a 1000 calories per day than you burn, exercise just makes you more hungry. The only way I can keep my weight down is to not eat everything I see at every opportunity.

I have been calorie counting now for nearly two years and I know if I can keep my average below 3500 per day my weight is good. My average 130 mile per week riding allows me this extra 1000 calories per day ( recommended 2500kCal per day for men) but this extra food is just lost in my near permanent state of being hungry. I think I am only ever truly satisfied on days I consume 6000 calories.

If cycling does have an impact on diet it is only that food tastes better than ever.

a tad surprised that you can eat an extra 1,000 calories a day even with that cycling and not gain weight.
I did lose some weight a few years ago using the myfitnesspal app and trying to calorie count to 1,500 calories a day with some moderate cycling each day.
It did work and I can recommend the app.
One thing it did highlight to me - as simon says - cycling is damn efficient - even with the hills round my way I don't think I was burning off that many calories though it did help.
I was probably actually taking in a bit more than 1,500 a day - hard to count exactly - but a good aim.

Indeed - I have no idea what my non cycling calorie intake should be, since I started calorie count nearly 2 years ago I have not sopped cycling, I'm a fairly active person even without my cycling and maybe I could keep a stable weight with more than 2500 per day ?

During the two years of calorie counting all I have really established is below 3000 per day I loose weight, above 4000 I gain. More cycling (200 mile + per week) certainly looses weight at 3500 kcal per day but how much extra I could eat at 200 mile per week and not gain weight I have no idea.

I have also found that weight gain and loss is not that straightforward, there seems to be some sort of delay - ie eat 6000 a day for a week and it is may be a fortnight later before the consequences appear - its all a bit odd.

[mattheus]

Probably running burns slightly more calories per hour, but otoh you can cycle all day much easier than you can run.

Have a look at the ACSM Compendium of Physical Activities I linked above, it lists the energy consumption for just about every conceivable activity: walking, cycling, running, washing the pots, having sex........

kcal per mile temp.png

This graph is rather unhelpful to the topic of exercise.

One exercises for an hour, or two hours, or whatever, not for a certain number of miles. Doing an hour at 20mph will burn hugely more calories than at 10mph, but this graph does not show that very well.

Agreed - calories-per-hour would be much more helpful for most people in most situations. (and I think it's the more commonly stated metric)

Sorry for picking on your post, mr Knutt!

[simonineaston]

Peter Hitchens on cycling and weight loss

The linked article is a delight to read - a snapshot of a bygone day. Thanks. What a pair of brothers, Chris and Peter... so different!

[mumbojumbo]

Are they the ones that made the dodgy frames ridden by eccentrics.

[Blondie]

But is there a correlation between cycling and weight? If you took 10,000 people who cycled at least 4-5 days a week throughout the year, and had done for many years, and compared that to 10,000 sedentary people, how would their weights compare stratified by age and gender etc?

Weight gain isn’t an instant thing, it happens over many years and decades. It creeps up on people. Why people try to lose the weight in months, when it took years to gain I know not.

[Jdsk]

But is there a correlation between cycling and weight? If you took 10,000 people who cycled at least 4-5 days a week throughout the year, and had done for many years, and compared that to 10,000 sedentary people, how would their weights compare stratified by age and gender etc?

It might depend on which factors you match, but I'd expect the frequent cyclists to have lower body mass.

But there would be many possible causes.

Jonathan

[Dingdong]

It’s worth being very wary of the “men need 2500kcal each day” thing too.

Just out of curiosity, I monitored my calorie burn on ‘non cycling’ days by using a Fitbit watch for a while, and assuming it to be accurate if demonstrated that c2500kcal amounts to a pretty busy/active day. When I was working full time and commuting I did get through that, like wise of at home on a busy day, or on a day out, but have an easy day, go to the cinema, spend s couple of hours driving somewhere and ….. far less energy burned. I reckon an easy day only uses 1500-1800.

I think (from experience of using a variety of fit watches) you have to be very sceptical of any feedback you get from them. It's rarely accurate and is really just a good guess by a relatively simple algorithm. Measuring calorie expenditure is fiendishly complicated, but I did see a good Ted talk which explains the mechanism of losing weight, which actually boils down to the exhalation of carbon dioxide. 84% of fat burned is exhaled in the form of CO2, it is actually burned off, and the by product is a gas.

It's an interesting article:

https://weightlessmd.com/mathematics-of ... loss-tedx/

[Pebble]

But is there a correlation between cycling and weight? If you took 10,000 people who cycled at least 4-5 days a week throughout the year, and had done for many years, and compared that to 10,000 sedentary people, how would their weights compare stratified by age and gender etc?

It might depend on which factors you match, but I'd expect the frequent cyclists to have lower body mass.

But there would be many possible causes.

Jonathan

I keep myself very lean purely because being light means my cycling is easier and more enjoyable. I continuously diet because of my cycling obsession, if I had no bike I would eat a lot more and be a good bit heavier. So being a cyclist keeps me thin but has little to do with the exercise.