腕立ては10秒間で最大何回できるか。物理的な限界【物理エンジン】

(Machine translation by DeepL translate)I wonder what the limit is for the number of push-ups.

The maximum number of push-ups per time seems to be determined by physical conditions, not muscle strength.

First of all, let's think about the shortest time you can take to lower your body.

When you lower your body, you can't pull the ground.

The shortest time is when you don't use your hands and let gravity do the work.

No matter how hard you work out, you will never be able to lower your body faster than this.

If we assume that the body is upright and model it on a board

The time to reach the ground (independent of mass) can be written as

If you are 170cm tall and θ0=15°, you will hit the ground in 0.25 seconds

If the height is different

Even if the initial angle is the same, the time will change a little.

This is the minimum time for lowering the body in a push-up

Next, the minimum time for lifting up the body

As soon as the body is lowered, push off the ground.

You want to lift your body as fast as possible.

But since your hands are not fixed to the ground

If you lift too fast, your body will float and you will lose time.

So I want to lift my body as fast as possible without floating.

Think of a board that bounces a lot.

The time it takes to return to the initial height where your arms are fully extended

The time it takes for the arm to return to the initial height where it is extended is equal to the time it takes for the arm to fall under gravity.

The minimum time required for one push-up can be approximated as follows

Now we know the maximum number of pushups we can do in one second.

If you are stretched out, and your height and arm length are not too extreme, the upper limit will be around 2 times per second.

The limit depends on gravity, so let's change the location.

The moon has 1/6 the gravity of the earth.

You can't do push-ups at the fastest pace on Earth because the time needed per push-up is longer.

The upper limit is about 0.8 times per second.

Let's go to a planet where the gravity is 10 times that of the earth.

Whether you can do it or not, the upper limit on this planet is more than 6 times per second.

This is how gravity changes the upper limit.

Earth again

We now know the theoretical upper limit of push-ups. But when I did a search for "high speed push-ups," I found

I found someone who can do 34 in 10 seconds!

So far, he should only be able to do about 20 in 10 seconds.

But all the "people competing for the most times" don't have their bodies in a straight line!

It seems that this is how they manage to avoid the limits of the plate model!

As long as you are chasing the number of times, it is physically inevitable that you will end up in a strange posture

That's what I thought.

The end