Just being able to stand up or to walk, is one of the most amazing tricks it is possible to learn! It is a trick, and it must be learned.
If a four-legged visitor from another planet came to see us, he would marvel at the ability we have to do this. If he tried to do it, it' would take him a considerable time to learn the trick, just as it took time for you to learn it when you were a baby.
When you stand still, you are performing a constant act of balancing. You change from one leg to the other, you use pressure on your joints, and your muscles tell your body to go this way and that way.
Just to keep our balance as we stand still takes the work of about 300 muscles in our body! That is why we get tired when we stand. Our muscles are constantly at work. In fact, standing is work!
In walking, we not only use our balancing trick, but we also make use of two natural forces to help us. The first is air pressure. Our thigh bone fits into the socket of the hip joint so snugly that it forms a kind of vacuum. The air pressure on our legs helps keep it there securely. This air pressure also makes the leg hang from the body as if it had very little weight.
The second natural force we use in walking is the pull of the earth's gravity. After our muscles have raised our leg, the earth pulls it downward again, and keeps it swinging like a pendulum.
When you see an acrobat walking across a tightrope and balancing himself, remember he is only doing a more difficult trick of balancing than you do every day. And like you, he had to learn and practice it for a long, long time!
If a four-legged visitor from another planet came to see us, he would marvel at the ability we have to do this. If he tried to do it, it' would take him a considerable time to learn the trick, just as it took time for you to learn it when you were a baby.
When you stand still, you are performing a constant act of balancing. You change from one leg to the other, you use pressure on your joints, and your muscles tell your body to go this way and that way.
Just to keep our balance as we stand still takes the work of about 300 muscles in our body! That is why we get tired when we stand. Our muscles are constantly at work. In fact, standing is work!
In walking, we not only use our balancing trick, but we also make use of two natural forces to help us. The first is air pressure. Our thigh bone fits into the socket of the hip joint so snugly that it forms a kind of vacuum. The air pressure on our legs helps keep it there securely. This air pressure also makes the leg hang from the body as if it had very little weight.
The second natural force we use in walking is the pull of the earth's gravity. After our muscles have raised our leg, the earth pulls it downward again, and keeps it swinging like a pendulum.
When you see an acrobat walking across a tightrope and balancing himself, remember he is only doing a more difficult trick of balancing than you do every day. And like you, he had to learn and practice it for a long, long time!
