From the point of view of the Law of Conservation of Energy.

A note, in no way connected with Bell Kaufman’s novel “Up the stairs leading down”!

But also, in a way, “autobiographical.”

I live on the eleventh floor of a nineteen-story building and try to walk up and down stairs instead of using the elevator. Not because I don’t like or am afraid of “enclosed spaces” (claustrophobia), but simply to maintain physical tone.

When I lived in another thirty-storey building on the tenth floor, I also often ran up the stairs from below to my floor in 47 seconds “for sport.”

And such an “energetic” oddity has been scratching at the brain for a long time: whether we climb with our LEGS to a certain height or descend, our muscles do the same work, and if we spend the same time, we develop the same power.

So why don’t we feel any stress or fatigue when we go down, but HOW do we feel when we go up?

After all, in both cases it is the same potential energy of our body, and in both cases, when we ascend or descend, our kinetic energy is zero, both above and below. This means that when descending, our muscles take on all the potential energy accumulated by altitude and, contracting, “extinguish” it. So, why is there such a difference in sensations?

A seditious idiotic thought flashed across that this Conservation Law could not be applied to a living organism. But I immediately rejected it, especially since the doctor Robert Julius Mayer discovered this great basic law of nature by invetigatoing the color the blood of sailors on a ship in the forties of the nineteenth century!

In general, I realized that it was necessary to reason “NOT AT ALL” from the point of view of conservation of potential and kinetic energy, but to consider in DETAIL the difference in muscle function when climbing stairs and descending.

Here in the “little details” lies the solution!

When we descend, of course, many muscles of our body work, but the main work of dampening the speed of descent on each step is done only by the calf muscles. We bend the leg a little bit, that is, the thigh muscles are activated, tightening the lower part, shin and foot, slightly upward and that’s it.

Immediately– there is an intermediate conclusion: DURING DESCENT AND ASCENT, the work of muscles is incomparably different energetically and there is no connection at all with the law of conservation of energy, because the cost of muscle effort is DIFFERENT!

When climbing, before each step, we use our muscles to lift the leg up to the hip joint to the height of the step (which we did NOT do when descending!). And the leg WEIGHS a lot!

Secondly– when we put it on a step, a whole series of muscles are triggered, tilting our body slightly forward, then the extensor muscles of the leg begin to contract with great effort, and “working” against the “unfavorable lever” in order to straighten the leg bent at the knee and it lifts the entire body weight to the next step, the centipede muscle of the other leg helps it., also “working” against the unfavorable leverage of one to seven!!! This is all a very significant effort, incomparable in terms of energy costs with the descent. And this happens with a step-by-step ascent.

(I’m not even talking about my way of taking one step at a time and taking steps up, immediately overlapping two steps vertically. There, the load on the sartorial muscles, calf muscles and all the others is even greater, and many must work against an UNFAVORABLE LEVER.)

I remember from Ralph Gerrard’s excellent book “The Functions of the human Body”, which I read in my youth, that the force of contraction, for example, of the calf muscle is enormous!

He gives this example:

If you weigh 70 kg. and stand on tiptoe, standing on one leg, your muscle develops a force of 490 kg, because pulling the foot up from behind, it works against the lever one to seven. And if you wrap your arms around another with the same weight person and lift up on one leg with them, then only ONE of YOUR calf muscle develops ONE TON of strength!

So, the summary:

The Law of Conservation of Energy is unshakable, but it simply does NOT APPLY to this case, because different muscles work in different ways!

I answered my stupid question with a sober and sensible explanation!

Moral: Don’t ask stupid questions, or at least try to avoid them!

5 I 2026