A question about the gym

[TheBitterEnd]

torque required from the engine is the same

I don't think it is. On the treadmill the torque is that required to hold the car in place, i.e. sufficient to counterbalance the gravitational acceleration but on the ramp the torque has to be greater than the gravitational force to not just hold the car in place but move it up the ramp.

But on the treadmill, that energy doesn't become gravitational potential energy - so where does it go?

It becomes heat. Consider dong a hill start in a car, you can remain stationary by balancing the downhill force with clutch slip, which heats up the clutch.

 

[ChrisB]

the torque has to be greater than the gravitational force to not just hold the car in place but move it up the ramp.

The torque has to be greater to accelerate it up the ramp, but once it's moving it only needs to match gravity.

The hypothetical car had a control mechanism to regulate its speed that doesn't produce heat.

 

[mikem]

Work = force x distance
Steve Mould is correct with the horizontal treadmill comparison, but not the vertical component, as the treadmill makes no height, whilst the hillwalker does (on a low incline the horizontal effort will be proportionally greater than the vertical, so difficult to notice latter). Similarly on the rolling ladder they didn't climb anything like the same distance when it was stationary (which is precisely the problem he noted with doing it inside a lift, although the other way around)...

 

[mikem]

& he did in fact get a 10% greater power usage for the hill over the inclined treadmill (his explanation of the car slipping on the latter doesn't hold water, as that would require more power to regain its position, so the difference may have been greater)

 

[Cantclimbtom]

Work = force x distance
Steve Mould is correct with the horizontal treadmill comparison, but not the vertical component, as the treadmill makes no height, whilst the hillwalker does (on a low incline the horizontal effort will be proportionally greater than the vertical, so difficult to notice latter). Similarly on the rolling ladder they didn't climb anything like the same distance when it was stationary (which is precisely the problem he noted with doing it inside a lift, although the other way around)...

Not exactly.
Imagine you are standing still on the belt of an incredible long treadmill, let's call it infinite.
The treadmill is moving slowly at a constant speed and inclined downwards. It takes no work for you to stand still.
You are descending due to the downwards inclination but if you shut you eyes you couldn't tell. Any work done/changes in potential energy due to gravity are all happening with the treadmill. You are just standing still on the belt.
As a result, if you walk up the treadmill from some mark on the belt belt you are gaining height relative to the mark in the belt. That takes your effort.

If you don't believe me set a treadmill to 15 degrees (max of many commercial treadmills) and 4kph and walk for 5 mins, it's only 4kph. You will not gain height relative to the room. Come back and tell if that is easier or harder than jogging on a flat treadmill

 

[TheBitterEnd]

f you don't believe me set a treadmill to 15 degrees (max of many commercial treadmills) and 4kph and walk for 5 mins, it's only 4kph. You will not gain height relative to the room. Come back and tell if that is easier or harder than jogging on a flat treadmill

Back to the original question then, yes an inclined treadmill is harder than a flat one but not as hard as a real hill. Consider a point on the walker's head. On the inclined treadmill the walker steps up and starts to lift their body, the point on the walker's head starts to move up but as the walker's leg extends the foot moves down as the belt moves so the point on walker's head never moves up by the full height of the step.

On an actual hill the walker's head does move up by the full height of the step

 

[Cantclimbtom]

Back to the original question then, yes an inclined treadmill is harder than a flat one but not as hard as a real hill. Consider a point on the walker's head. On the inclined treadmill the walker steps up and starts to lift their body, the point on the walker's head starts to move up but as the walker's leg extends the foot moves down as the belt moves so the point on walker's head never moves up by the full height of the step.

On an actual hill the walker's head does move up by the full height of the step

Personally I believe whether dressed up using fancy terminology like "Galilean relativity" or just from thinking about it, that the height gained whether relative to the treadmill (descended point on belt) or relative to altitude and ground in real hills is equivalent.

But comparing walking on a perfectly smooth/even rubber and slightly springy treadmill is not a fair comparison to hard and uneven ground outdoors. I think this is the answer. A similar disparity can be felt comparing jogging on a flat treadmill and jogging on flat pavements.

You could argue that treadmills are some the least useful bits of kit in a gym given most of the time you could've walked or jogged outdoors.

The Stairmaster/stair climber I thought was just some joke equipment for sweaty fat people. Trying one was a humbling experience and I learned they're to be respected! And probably has closer equivalence to climbing real hills/stairs

 

[Jim MacPherson]

The Stairmaster/stair climber I thought was just some joke equipment for sweaty fat people. Trying one was a humbling experience and I learned they're to be respected! And probably has closer equivalence to climbing real hills/stairs

At the prices they seem to be asking that's just as well but I'll just stick to doing a few sets of five up my single flight of stairs (even that's rather boring). I shall have to wait until my hip/thigh muscles can take more punishment and I can start to do some walking, preferably up and down hills, other than a trundle to the village shop and collecting doggie gifts in the garden. Sorry to be grumpy but I'm rather disliking aspect of older age and hip replacement/muscle weakening and envy people that have the options.

Jim

 

[Cantclimbtom]

At the prices they seem to be asking that's just as well but I'll just stick to doing a few sets of five up my single flight of stairs (even that's rather boring). I shall have to wait until my hip/thigh muscles can take more punishment and I can start to do some walking, preferably up and down hills, other than a trundle to the village shop and collecting doggie gifts in the garden. Sorry to be grumpy but I'm rather disliking aspect of older age and hip replacement/muscle weakening and envy people that have the options.

Jim

Years ago my mum had a hip replacement and it did wonders for her. She was given dire warning not to sit with legs crossed or swim with the kick of breast stroke (no more frog kick if you're a diver). But apart from those restrictions it worked for her!!
Get well soon

 

[Chocolate fireguard]

Isn't it lucky that years ago, when scientists were sorting out the Principle of Conservation of Energy, they didn't have exercise treadmills, toy cars or UKC to distract them?

 

[mikem]

That's why he got a higher result for inclined treadmill than flat one, but still lower than actually going up the slope...