Cycling equivelant to marathon

[captainhastings]

I think this article gets it about right for me and my experiences as a cyclist and runner.

http://davesbikeblog...g-calories.html

Good article and feels about right too me too I have been doing a 15-20 mile ride instead of my normal 5 mile run due too injury and it sort of feels the same amount of effort just in a different way.
Not that it matters one jot at the end of the day as long as I am doing some thing

 

[Angelfishsolo]

superman.

That should have been 26 mile btw

 

[twobiker]

The London marathon course seems to be fairly flat and therefore there wouldn't be much chance for freewheeling if you rode it on a bike, its not like with like, its just the runners trying to make out its harder than cycling, the kenyans don't seem to find it that hard, if you had to run 26mls where I live it would take a lot longer than 4hrs, don't forget runners don't have to stop at red lights.

 

[oldfatfool]

The cyclist can also freewheel, if the runner stops moving their legs, they come to a stop. Also on a bike, you arent carrying your own weight, your weight is being carried by the machine. Not forgetting that running utilises a larger muscle group.

I have to disagree with most points you make, in order to freewheel the cyclist must have provided the stored energy in the bike to allow it to move, it is not free it as to come from somewhere. You are still carrying your own weight on a bike, be it through your arse bone or your feet, you are also having to provide the energy to move the extra weight of the bike, they don't come with a lifetimes supply of free kinetic energy from the lbs.

Yes the way in which your body supplies the energy as greater impact with running and it is a lot less efficient (greater heat loss) but the actual kinetic energy used will be greater in cycling. Kinetic energy = 1/2 MV[sup]2 [/sup](M = mass, V = velocity)

The bike does come with free potential energy but this is only converted to kinetic energy by the input of the rider or some external force eg. gravity, downhill. Unfortunately in order for gravity to provide 'free' energy the bike as got to be at the top of a hill, in order to get to the top of the hill and freewheel then gravity must be overcome in the first place and the extra energy to do this is =[sub]>[/sub] the 'free' energy on the other side.

It is only due to the inefficiencies of running and the fact that it is a high impact activity over a LONGER PERIOD for the equivalent distance that it is more draining on the body. I will stick to with my own conclusions

a) A marathon is a marathon in terms of energy required to move an equivalent weight an equivalent distance (not taking into account heat losses through friction etc etc)

b) In order to replicate a marathon on a bike (to take stamina heat loss etc in to effect) it will be a distance slightly shorter that the average person can cycle in the time it took the same average person to do the marathon.

c) If you have any sense you are better off cycling than running

edit: just read the article refferred to above which would appear broadly agree with my statement b) ie if the average person takes 4 1/2 hours to complete a marathon then the equivelent is a 41/2 hour bike ride, from the article that would mean cycling at an average of 18 mph

ie a marathon 26 miles, costs a runner 2860 cals in order to burn this number of calories over 4.5 hours a cyclist must burn 635p/h ie approx 18 mph and hence 81 miles on a bike = a marathon in terms of calories (less than I originally thought in my 1st post)

Don't get me wrong, I can cycle 81 miles and on the flat probably do it in 4.5 hours, I can walk 26 miles and not break a sweat, and according to the article both will cost me the same amount of energy and be equal to running the 26 mile at any speed. COULD I RUN A MARATHON could I coco

 

[twobiker]

I have to disagree with most points you make, in order to freewheel the cyclist must have provided the stored energy in the bike to allow it to move, it is not free it as to come from somewhere. You are still carrying your own weight on a bike, be it through your arse bone or your feet, you are also having to provide the energy to move the extra weight of the bike, they don't come with a lifetimes supply of free kinetic energy from the lbs.

Yes the way in which your body supplies the energy as greater impact with running and it is a lot less efficient (greater heat loss) but the actual kinetic energy used will be greater in cycling. Kinetic energy = 1/2 MV[sup]2 [/sup](M = mass, V = velocity)

The bike does come with free potential energy but this is only converted to kinetic energy by the input of the rider or some external force eg. gravity, downhill. Unfortunately in order for gravity to provide 'free' energy the bike as got to be at the top of a hill, in order to get to the top of the hill and freewheel then gravity must be overcome in the first place and the extra energy to do this is =[sub]>[/sub] the 'free' energy on the other side.

It is only due to the inefficiencies of running and the fact that it is a high impact activity over a LONGER PERIOD for the equivalent distance that it is more draining on the body. I will stick to with my own conclusions

a) A marathon is a marathon in terms of energy required to move an equivalent weight an equivalent distance (not taking into account heat losses through friction etc etc)

b) In order to replicate a marathon on a bike (to take stamina heat loss etc in to effect) it will be a distance slightly shorter that the average person can cycle in the time it took the same average person to do the marathon.

c) If you have any sense you are better off cycling than running

edit: just read the article refferred to above which would appear broadly agree with my statement b) ie if the average person takes 4 1/2 hours to complete a marathon then the equivelent is a 41/2 hour bike ride, from the article that would mean cycling at an average of 18 mph

ie a marathon 26 miles, costs a runner 2860 cals in order to burn this number of calories over 4.5 hours a cyclist must burn 635p/h ie approx 18 mph and hence 81 miles on a bike = a marathon in terms of calories (less than I originally thought in my 1st post)

Don't get me wrong, I can cycle 81 miles and on the flat probably do it in 4.5 hours, I can walk 26 miles and not break a sweat, and according to the article both will cost me the same amount of energy and be equal to running the 26 mile at any speed. COULD I RUN A MARATHON could I coco

My 16yr old daughter rode 81 miles on an old Hybrid bike with knobblies, the time element is the difference, you can do a marathon in a diving suit, it depends how long you want to take.

 

[Rob3rt]

The London marathon course seems to be fairly flat and therefore there wouldn't be much chance for freewheeling if you rode it on a bike, its not like with like, its just the runners trying to make out its harder than cycling, the kenyans don't seem to find it that hard, if you had to run 26mls where I live it would take a lot longer than 4hrs, don't forget runners don't have to stop at red lights.

You can still momentarily relax by freewheeling even on the flat. As for the red light thing, then go running and find out for yourself, not stopping, means no rests. In addition, coming from my experience, green lights are the runners enemy as they stop your progress when you cant cross a road and either have to stop or run detours to keep moving.

I have to disagree with most points you make, in order to freewheel the cyclist must have provided the stored energy in the bike to allow it to move, it is not free it as to come from somewhere. You are still carrying your own weight on a bike, be it through your arse bone or your feet, you are also having to provide the energy to move the extra weight of the bike, they don't come with a lifetimes supply of free kinetic energy from the lbs.

Yes the way in which your body supplies the energy as greater impact with running and it is a lot less efficient (greater heat loss) but the actual kinetic energy used will be greater in cycling. Kinetic energy = 1/2 MV[sup]2 [/sup](M = mass, V = velocity)

The bike does come with free potential energy but this is only converted to kinetic energy by the input of the rider or some external force eg. gravity, downhill. Unfortunately in order for gravity to provide 'free' energy the bike as got to be at the top of a hill, in order to get to the top of the hill and freewheel then gravity must be overcome in the first place and the extra energy to do this is =[sub]>[/sub] the 'free' energy on the other side.

It is only due to the inefficiencies of running and the fact that it is a high impact activity over a LONGER PERIOD for the equivalent distance that it is more draining on the body. I will stick to with my own conclusions

a) A marathon is a marathon in terms of energy required to move an equivalent weight an equivalent distance (not taking into account heat losses through friction etc etc)

b) In order to replicate a marathon on a bike (to take stamina heat loss etc in to effect) it will be a distance slightly shorter that the average person can cycle in the time it took the same average person to do the marathon.

c) If you have any sense you are better off cycling than running

edit: just read the article refferred to above which would appear broadly agree with my statement b) ie if the average person takes 4 1/2 hours to complete a marathon then the equivelent is a 41/2 hour bike ride, from the article that would mean cycling at an average of 18 mph

ie a marathon 26 miles, costs a runner 2860 cals in order to burn this number of calories over 4.5 hours a cyclist must burn 635p/h ie approx 18 mph and hence 81 miles on a bike = a marathon in terms of calories (less than I originally thought in my 1st post)

Don't get me wrong, I can cycle 81 miles and on the flat probably do it in 4.5 hours, I can walk 26 miles and not break a sweat, and according to the article both will cost me the same amount of energy and be equal to running the 26 mile at any speed. COULD I RUN A MARATHON could I coco

On a bike your body does not need to support itself to the extent it does when running, in addition a larger muscle group is used running due to the more complex motion, plus the muscles required to stabilise the body consume energy.

Also when running the direction of the forces your body must exert and overcome are presented differently to when cycling, so your equations for a 'point object' are not very illustrative here (btw I'm fairly familiar with high school physics). Cycling you are essentially pushing mostly downwards (even an efficient rider with a smooth pedal stroke will most be pushing downward), this application of force is aided greatly by body weight, in running not only is your weight supported by your muscular system, your major effort is to progress forward, involving a complex motion that involves downward and backwards forces which must be balanced with frictional forces.

The bicycle essentially converts downward force (aided by body weight) to forward motion, running involves overcoming downward forces in order to progress forward. You can talk about inertia here being that both sports require you to overcome inerta if you really want to, it doesnt make much difference to the arguement though.

I think you are vastly over simplifying the science here, to get to the bottom of the science is beyond the scope of this thread really imo.


In downright, equivalent terms of difficulty between a marathon and a set cycling distance, you would not only need to exert similar levels of exertion on the energy supply systems, but also give the body an equal battering and the mind a mental battering. Its just daft to reduce this comparison to the body's energy systems and silly high school equations which barely apply. IMHO in the real world they just arent comparable.

 

[Bobtoo]

Cycling becomes less efficient as you go faster due to wind resistance, while on foot the efficiency is much the same regardless of speed. That's why there can never be an equivalent based on distance alone.

 

[oldfatfool]

In downright, equivalent terms of difficulty between a marathon and a set cycling distance, you would not only need to exert similar levels of exertion on the energy supply systems, but also give the body an equal battering and the mind a mental battering. Its just daft to reduce this comparison to the body's energy systems and silly high school equations which barely apply. IMHO in the real world they just arent comparable.

Well of course I have simplified the science, but to dismiss the laws of thermodynamics (and how the universe operates) as silly school equations which don't apply is just ludicrous

The faster you run a marathon the quicker you will burn the 2900 cals but at the end it will still be 2900 cals.

So to be accurate and compare a run to a cycle we would have to have the cyclist burning the same 2900 cals in the same time, same expenditure of energy over the same time, OR completing 26 miles and having done so expanded 2900 cals. which looking at the table from the above link would have the cyclist averaging approx 55 mph for approx 35 mins.

I would argue that the latter would be mentally and physically more taxing than running the marathon, but the same amount of energy is used.

I agree it is impossible to compare the two in real life, a good runner may be a crap cyclist and vice versa so the only way you can express it is by looking at the energy required.

 

[amaferanga]

Well of course I have simplified the science, but to dismiss the laws of thermodynamics (and how the universe operates) as silly school equations which don't apply is just ludicrous

The faster you run a marathon the quicker you will burn the 2900 cals but at the end it will still be 2900 cals.

So to be accurate and compare a run to a cycle we would have to have the cyclist burning the same 2900 cals in the same time, same expenditure of energy over the same time, OR completing 26 miles and having done so expanded 2900 cals. which looking at the table from the above link would have the cyclist averaging approx 55 mph for approx 35 mins.

I would argue that the latter would be mentally and physically more taxing than running the marathon, but the same amount of energy is used.

I agree it is impossible to compare the two in real life, a good runner may be a crap cyclist and vice versa so the only way you can express it is by looking at the energy required.

I would argue that the latter would be impossible by a long, long way. The Wattage required to do that (around 1380W) would be way way beyond what any person could do. 1380W for 5 seconds would be considered pretty decent for a world class sprinter! Even to burn 2900kCal in 2 hours would require a Wattage of around 400W. For the hour record set by Boardman his power output was around 445W so I doubt anyone could average 400W for two hours.

But as has been pointed out and alluded to several times there's more to it than just the energy used since cycling isn't weight bearing.

 

[twobiker]

I've come from a running back ground the big thing in that world is the marathon 26.2 miles is there a cycling equivelant i.e distance in miles as don't do kilometers if I can help it.

Perhaps if you tell us how long a marathon takes you then maybe the answer would be clearer?.

 

[oldfatfool]

I would argue that the latter would be impossible by a long, long way. The Wattage required to do that (around 1380W) would be way way beyond what any person could do. 1380W for 5 seconds would be considered pretty decent for a world class sprinter! Even to burn 2900kCal in 2 hours would require a Wattage of around 400W. For the hour record set by Boardman his power output was around 445W so I doubt anyone could average 400W for two hours.

true, but this extreme proves my point when folks are saying running is harder than cycling, it all depends on the time over which the energy is delivered.

But as has been pointed out and alluded to several times there's more to it than just the energy used since cycling isn't weight bearing.

It is still weight bearing, just on a differant part of the anatomy and with lower pressure due to greater surface area, and cycling is a low impact activity ie your entire weight is not being transferred through a couple of sq " with every step as it is with running, instead on a bike the bulk is constant through the size of your bum, (larger arse less effort?????)

If you where to stand the entire time on your pedals then maybe the comparison would be closer??

 

[Rob3rt]

Well of course I have simplified the science, but to dismiss the laws of thermodynamics (and how the universe operates) as silly school equations which don't apply is just ludicrous

The faster you run a marathon the quicker you will burn the 2900 cals but at the end it will still be 2900 cals.

So to be accurate and compare a run to a cycle we would have to have the cyclist burning the same 2900 cals in the same time, same expenditure of energy over the same time, OR completing 26 miles and having done so expanded 2900 cals. which looking at the table from the above link would have the cyclist averaging approx 55 mph for approx 35 mins.

I would argue that the latter would be mentally and physically more taxing than running the marathon, but the same amount of energy is used.

I agree it is impossible to compare the two in real life, a good runner may be a crap cyclist and vice versa so the only way you can express it is by looking at the energy required.

Forgetting that this arguement is completelly stupid in the real world, where do pull that the amount of energy used would be the same from?

true, but this extreme proves my point when folks are saying running is harder than cycling, it all depends on the time over which the energy is delivered.



It is still weight bearing, just on a differant part of the anatomy and with lower pressure due to greater surface area, and cycling is a low impact activity ie your entire weight is not being transferred through a couple of sq " with every step as it is with running, instead on a bike the bulk is constant through the size of your bum, (larger arse less effort?????)

If you where to stand the entire time on your pedals then maybe the comparison would be closer??

It doesnt prove your point at all. You might consider it proved, but I think that you are talking bollocks.

Its idle weight baring on your sit bones, that weight is supported for you, when running all of your weight is supported by the skeletal and muscular system, if you cant see that this is different then I'm at a loss.

 

[oldfatfool]

then I'm at a loss.

I can tell from your reasoned and well thought out argument

To give you a simile. If you try to lift a 50 kg weight through 1 mtr then the amount of energy you need will be X we will call this the runner. It will be hard.

If you then attach a system of ropes and pulleys you can make the job much easier but at the end of the day the amount of energy to move the weight 1m will still be X ie the same. (this is your cyclist)

 

[Rob3rt]

I can tell from your reasoned and well thought out argument

As opposed to yours?

 

[PorkyPies]

It doesnt prove your point at all. You might consider it proved, but I think that you are talking bollocks.

Its idle weight baring on your sit bones, that weight is supported for you, when running all of your weight is supported by the skeletal and muscular system, if you cant see that this is different then I'm at a loss.

I agree with you. You have a point and old guy dosn;t.