Cycle versus car - false economy?

[Ming the Merciless]

This is for a 69kg person, based on the additional calorie consimption over and above sedentary behaviour, and a food cost of £1.20/1000kcals, which is the average for my diet as of April 2022. (My food expenditure appears to be well below the figures I've seen bandied around at various times.)

View attachment 670257

Care to produce some evidence for that?

Suppose I drive my car 100 miles without stopping to fill the tank, does that prove it hasn't used any petrol? No, of course it doesn't.
Suppose I drive 10 miles on alternate days, and 90 miles on each day in between. If I stop and buy 50 miles-worth of petrol every day, does that prove the car will go 90 miles on the same amount of fuel it takes to travel 10 miles? No, of course it doesn't.
But that's exactly the same logic that you're applying to the bike. The point is if you stop driving 90 miles on alternate days, and drive 10 miles every day instead, your average daily mileage will have gone from 50m/day to 10m/day, and the amount of fuel you have to put in the tank will also have gone down accordingly.

Exactly.
And even if you are getting lighter, the journey is still being fuelled by fat that originally came from food, just like the car that's getting lighter if you don't stop for petrol.

I've given you the proof, you just choose to ignore it. The ACSM compendium is a peer reviewed data source that has been compiled from actual measurements of metabolic rate for over 800 everyday activities, specifically for the purpose of calculating the energy used. It's a standard reference that's been in use worldwide for nearly 30 years.

You've just admitted that you ARE using energy to get to Aldi, there.

Yes, you're absolutely right, and if you'd taken the trouble to calculate by how much, you'd see that it's trivial compared to the energy used by cycling. A 70 kg rider cycling 220 miles at 12mph (~6METs) will burn off about 1kg of fat (7800kcals), and in so doing will knock 14 kcals of his BMR. That 14 kcals is enough to take him 0.4 miles.

The cost of the bike/car/insurance/mot etc are only relevant if you're proposing to give one of them up altogether. Most people will want to own both and just be deciding which one to use, and which one to leave at home.

Either the fraction is 100%, or the cyclist will lose weight over the long term.

It's the emissions from agriculture you need to be looking at, they account for 26% of all greenhouse gases.

This. It's bleedin' obvious, innit.
Since my health put paid to exercise I'm eating less than 2000kcals/day, but when I was riding regularly it was about 3300, and on a 50m/day cycle tour 4500-5000. I've seen off as much as 7000 kcals in big day's ride.

You can multiply that cycling figure by several times over.

It can be, it depends what you're comparing with what:
View attachment 670258

If you go for a ride then fill up with a Big Mac on the way home, then your ride was powered by (mostly) beef, and your ride will have produced about the same emissions as a big 4x4.

The sedentary person simply puts on more weight, thus needing more calories to sustain themselves. The one who cycles stays in energy balance and eats less than the sedentary person.

 

[gzoom]

Sometimes you do wonder if cycle commuting is cheaper, especially when you've had a run on a new set of wheels, chain, cassette and chain rings, brake pads and tyres (all since summer).

Just paid for a first service on my commuter eBike. 5000 miles roughly, new drivetrain needed, £230. That's not too bad, but one of my two eBike batteries has developed a fault, £450 for a new one at todays prices. So 13.6p per mile.

Our EV costs 3p per mile in electricity, and tires are another 3p per mile. Maintenance over 45,000 miles was £900, so in total 8p per mile.

So based on cost per mile the EV is much cheaper than eBike. BUT the biggest 'issue' I have with commuting on the eBike is staying upright .

Two big offs this year already, the last one at the end of September literally knocked the socks off me, was pretty much immobile for a week, had to take time off work, and it was another 3-4 weeks before I could even think about riding a bike again. With temp going down to below zero this week, the eBike is going no where this week.

The bike is a fine toy for commuting/fitness, absolutely ZERO chance of it replacing the car for me, the fact it costs more to run than the car is just utterly mad, probably explain why so few people bikes for commuting in the UK,

 

[Ming the Merciless]

Our EV costs 3p per mile in electricity, and tires are another 3p per mile. Maintenance over 45,000 miles was £900, so in total 8p per mile.

So based on cost per mile the EV is much cheaper than eBike.

How much did the EV cost and how much did the e-bike cost?

 

[ColinJ]

Some - yes; all - no!

I don't drive and these days only get a small number of lifts a year. Nearly all of my utility journeys are done by bike or on foot. Most of the other journeys are by train or bus. I don't eat extra to fuel any of them.

Care to produce some evidence for that?

I'm sorry - the crew who were going to film me shopping and eating (and document details of all the food that I consumed) didn't turn up. You will just have to take my word for it!

You've just admitted that you ARE using energy to get to Aldi, there.

I'm not sure why you are adopting such a confrontational tone! It's a pity, because what you wrote was otherwise quite interesting...

I never said that food doesn't fuel my cycling, or that cycling does not burn energy. That would be plain wrong. Obviously!

I simply said that I don't eat or drink extra to fuel my cycling, unless I am riding, say, 40+ km. I eat the same amount - 1 or 2 meals a day - whether I am cycling or not.

At the moment, utility cycling costs me nothing extra in food and drink. You wouldn't be able to tell which days were utility cycling days by looking at my food and drink intake on those days.

At some point though, I will have to start eating extra or I will slowly wither away, but I am still a few kg over my target weight. I calculated in the past that I burn roughly 30 Cals/km on hilly rides so my 7 km shopping trips will cost me about an extra 200 Cals - say a couple of oatcakes or a few nuts and raisins.

 

[wafter]

This is for a 69kg person, based on the additional calorie consimption over and above sedentary behaviour, and a food cost of £1.20/1000kcals, which is the average for my diet as of April 2022. (My food expenditure appears to be well below the figures I've seen bandied around at various times.)

View attachment 670257

Care to produce some evidence for that?

Suppose I drive my car 100 miles without stopping to fill the tank, does that prove it hasn't used any petrol? No, of course it doesn't.
Suppose I drive 10 miles on alternate days, and 90 miles on each day in between. If I stop and buy 50 miles-worth of petrol every day, does that prove the car will go 90 miles on the same amount of fuel it takes to travel 10 miles? No, of course it doesn't.
But that's exactly the same logic that you're applying to the bike. The point is if you stop driving 90 miles on alternate days, and drive 10 miles every day instead, your average daily mileage will have gone from 50m/day to 10m/day, and the amount of fuel you have to put in the tank will also have gone down accordingly.

Exactly.
And even if you are getting lighter, the journey is still being fuelled by fat that originally came from food, just like the car that's getting lighter if you don't stop for petrol.

I've given you the proof, you just choose to ignore it. The ACSM compendium is a peer reviewed data source that has been compiled from actual measurements of metabolic rate for over 800 everyday activities, specifically for the purpose of calculating the energy used. It's a standard reference that's been in use worldwide for nearly 30 years.

You've just admitted that you ARE using energy to get to Aldi, there.

Yes, you're absolutely right, and if you'd taken the trouble to calculate by how much, you'd see that it's trivial compared to the energy used by cycling. A 70 kg rider cycling 220 miles at 12mph (~6METs) will burn off about 1kg of fat (7800kcals), and in so doing will knock 14 kcals of his BMR. That 14 kcals is enough to take him 0.4 miles.

The cost of the bike/car/insurance/mot etc are only relevant if you're proposing to give one of them up altogether. Most people will want to own both and just be deciding which one to use, and which one to leave at home.

Either the fraction is 100%, or the cyclist will lose weight over the long term.

It's the emissions from agriculture you need to be looking at, they account for 26% of all greenhouse gases.

This. It's bleedin' obvious, innit.
Since my health put paid to exercise I'm eating less than 2000kcals/day, but when I was riding regularly it was about 3300, and on a 50m/day cycle tour 4500-5000. I've seen off as much as 7000 kcals in big day's ride.

You can multiply that cycling figure by several times over.

It can be, it depends what you're comparing with what:
View attachment 670258

If you go for a ride then fill up with a Big Mac on the way home, then your ride was powered by (mostly) beef, and your ride will have produced about the same emissions as a big 4x4.

Crikey - that was comprehensive. Nice work

You make a very good point about energy expenditure above resting level. Working on a requirement for 1800kcal to satisfy basal metabolic rate suggests around 75kcal per hour when sedentary (not going to try to factor in the difference between sleep and waking) so at 50kcal/mile and 12mph (600kcal/hr) the cycling requires around four times BMR.

Your food seems cheap at £1.20/1000kcal - what's that based on? Do you live off bags of raw sugar?

The CO2 consumption is an eye-opener too, when compared to figures quoted for cars.. but again of course the vehicular argument only takes into account that released from the fuel during driving and neglects to account for production and transport of the fuel itself.

Unless you believe cyclists have the same weight as non cyclists, this must be true.

Bit of a bizarre, sweeping, unquantifiable statement that, is it not? Besides, I don't really see the relevance of rider mass to this argument. It's a basic premis of physics that you cannot create or destroy energy. Cycling expends energy. That energy comes from food. When energy intake exceeds expenditure the excess is stored as fat and the individual gains mass. When energy expenditure exceeds intake, fat is burned and the individual loses mass.

Yes, cycling might change fitness and metabolic rate (increasing the maximum rate at which energy can be burnt as well as the efficiency of energy conversion), but fundamentally for fat reserves to remain constant net energy input and net energy output must be equal.

Just paid for a first service on my commuter eBike. 5000 miles roughly, new drivetrain needed, £230. That's not too bad, but one of my two eBike batteries has developed a fault, £450 for a new one at todays prices. So 13.6p per mile.

Our EV costs 3p per mile in electricity, and tires are another 3p per mile. Maintenance over 45,000 miles was £900, so in total 8p per mile.

So based on cost per mile the EV is much cheaper than eBike. BUT the biggest 'issue' I have with commuting on the eBike is staying upright .

Two big offs this year already, the last one at the end of September literally knocked the socks off me, was pretty much immobile for a week, had to take time off work, and it was another 3-4 weeks before I could even think about riding a bike again. With temp going down to below zero this week, the eBike is going no where this week.

The bike is a fine toy for commuting/fitness, absolutely ZERO chance of it replacing the car for me, the fact it costs more to run than the car is just utterly mad, probably explain why so few people bikes for commuting in the UK,

View attachment 670266

That's interesting - the 'leccy for the car seems suspisciously cheap, while the ebike battery seems horrendously expensive (yet another reason I have no wish to own one).

Again I suspect this comparison is somewhat skewed as it doesn't take into account the depreciation on both vehicles - I suspect that of the car could pay for a complete bike in its entirity many times over!

 

[fossyant]

An ebike is going to sting you when either the motor or battery fail, and it's common. I'm in the car at the moment as covid lungs not great.

 

[roubaixtuesday]

Bit of a bizarre, sweeping, unquantifiable statement that, is it not? Besides, I don't really see the relevance of rider mass to this argument. It's a basic premis of physics that you cannot create or destroy energy. Cycling expends energy. That energy comes from food. When energy intake exceeds expenditure the excess is stored as fat and the individual gains mass. When energy expenditure exceeds intake, fat is burned and the individual loses mass.

I agree with you on the physics.

There is an assumption in that physics that nothing else changes between cyclists and non cyclists.

It's also a fact of biology that the more massive a person is, the more they metabolise.

I suggest to you that assuming that regular cyclists maintain the same mass they would without cycling is false - regular cyclists lose weight as a result.

Ergo, as well as the extra food they need due to the direct energy needed to cycle, they also need less as food as a result of maintaining a lower body mass.

So ascribing 100% of the extra energy to food intake is not the whole story - on average it will be less.

 

[All uphill]

I bet if I selected my data carefully enough I could prove that travelling by Boeing 747 is more economical than riding a Dawes Kingpin.

 

[Alex321]

I suggest to you that assuming that regular cyclists maintain the same mass they would without cycling is false - regular cyclists lose weight as a result.

Indeed. I started cycling regularly at the start of the first lockdown after very little for 20 years (I was swimming regularly, but not really enough), and without eating very differently, have lost just over 2 stone since then.

 

[Ming the Merciless]

but fundamentally for fat reserves to remain constant

Which is not what happens with sedentary individuals

 

[Ming the Merciless]

Plus

“
Although the commonly held notion is that more intensive workouts mean a person can burn more calories, a study has found that this view is not necessarily correct. The study reports that above a moderate level of physical activity, the total amount of energy consumed in one day by the body tends to level off—that means you don’t burn more calories, even if you increase your physical activity.

“Populations that have more active lifestyles don’t always have higher daily energy requirements than more sedentary populations,” says Herman Pontzer of City University New York and the lead researcher of the study.”

In other words whilst energy expenditure is higher during exercise the energy expenditure measured over a day is not higher.

 

[Jameshow]

Plus

“
Although the commonly held notion is that more intensive workouts mean a person can burn more calories, a study has found that this view is not necessarily correct. The study reports that above a moderate level of physical activity, the total amount of energy consumed in one day by the body tends to level off—that means you don’t burn more calories, even if you increase your physical activity.

“Populations that have more active lifestyles don’t always have higher daily energy requirements than more sedentary populations,” says Herman Pontzer of City University New York and the lead researcher of the study.”

In other words whilst energy expenditure is higher during exercise the energy expenditure measured over a day is not higher.

Wrong conclusion....

A more active population will have a lower metabolic rate than a sedentary population and thus will need to eat less.


In current days I wonder if you need more food to keep warm in a cold 15° house than if you did light or heavy exercise?!

 

[Ming the Merciless]

Wrong conclusion....

A more active population will have a lower metabolic rate than a sedentary population and thus will need to eat less.


In current days I wonder if you need more food to keep warm in a cold 15° house than if you did light or heavy exercise?!

Nevertheless a more active individual doesn’t necessary burn more calories per day than a sedentary equivalent

 

[gzoom]

I bet if I selected my data carefully enough I could prove that travelling by Boeing 747 is more economical than riding a Dawes Kingpin.

Did you not attend man maths University .

My previous calculations informed me our current EV is almost 'free' to own for the last few years, and currently am woekinf up a thesis on why a £5k eBike that I will never ride but in middle of summer is an 'essential' purchase!!

Biggest 'issue' I have with bike vs car is essentially my inability not to throw my soft squishy flesh against hard tarmac.

The car is infinitly better at keeping my limbs attached to my body versus the bike.

 

[Jameshow]

Nevertheless a more active individual doesn’t necessary burn more calories per day than a sedentary equivalent

I agree unless doing serious miles!

I reckon doing a century requires 1000cals!