Why is it easier to lift a person when they are standing upright, as opposed to when they are lying on the floor, or lifting a dead weight?



Like it’s easier if you hug their legs while they are standing up and hoist them up. I had a short friend who was able to do lift me when I was a kid, and could hold me in the air for at least a few seconds. How was this possible? Which muscles were important? Was it more about strength or technique?Is lifting someone heavier than you an impressive feat?

In: Physics

I would say you have to bend over less but also there’s a lot of friction involved in a hug lift that is missing lifting from the floor. Friction means you don’t need as much strength to maintain grip. All the strength goes into lifting. Try a hug type lift with just your hands to give you grip. Should be much harder.

If you think about it in terms… has anyone ever seen a dancer being lifted in the ballet or perhaps a gymnast or an acrobat? Now it might not look like the person being lifted is actually doing very much. It looks like the person doing the lifting is doing all the work but actually, that dancer or that gymnast is doing a lot. They’re using their core muscles to help hold themselves up and I think that’s probably what your daughter does when she’s awake. She’ll be sort of holding her muscles in a way that makes it easy to pick her up. She might even sort of wrap her hands around your neck and hold on and that helps spread her weight so that you’re carrying her with you arms, but some of her weight is actually going down through your shoulder and your back which is stronger than your arms so she doesn’t feel as heavy. Now when we go to sleep, we basically lose all of the control of our muscles. We become paralysed, we become completely relaxed and floppy and you may have noticed if you pick up someone when they’re asleep, they can be a bit like a rag doll sort of flopping all over the place. So her muscles won’t be engaging in order to help with the lifting and, actually, what you’re doing, you’re feeling her full weight. It’s not any more than she weighs, she hasn’t actually put on any weight but you’re feeling every pound of that weight because she’s not helping.

Very simply: the weight of a person (who’s alive and ideally awake) is more evenly distributed.

The reason for that is their body trying to balance itself on the point of contact where most of their weight lies. Your whole body is always actively working to keep you from falling over. The majority of its experience with that is while being upright (walking, standing, sitting in various positions).

Lifting an upright person while grabbing them anywhere from their hip downward and while their torso is upright is the most likely scenario where their weight will be most evenly distributed.

Why evenly distributed weight is easier to lift is another question. More weight being directly above your movement is a factor. Imagine trying to lift a gallon of water in a thin plastic bag. It’s variable form will make that harder.

All of this is very simplified, but should point you in the right-ish direction.