Why do you move your arms when you run?

Question:

my son says momentum. anyone got any other ideas?

i was running yesterday..with out thought i started moving my arms, then became aware they were moving.

i tried to run with them hanging straight down. felt odd. but i ran the rest of the way focused on keeping my arms hanging straight down.

p.s. i've been working all night..on day light savings..so i'm extra tired and thinking thoughts to keep me awake a couple of more hours

Answers:
for balance

I dont know maybe balence

You do it to keep your body in balance. The odd feeling you got was your brain trying to keep you in line.

it can make you go faster.

For Balance and the pumping motion that they provide. Try running up a steep hill with out pumping your arms, nearly impossible. It also helps your body flow better, when you pump your right hand and arm up your muscles tighten and stretch a little. For some reason that is the way our body works.

im not exactly sure either
but i kno that the faster u move ur arms, the faster ur legs will move
when u get tired, make sure ur arms are still moving
if u dont believe me, sit on the floor with ur legs straight out in front of u
move ur arms as if u were running
when u go fast, u will start to bounce, and ur legs will sway from side to side
the faster u go the more u bounce, and the more ur legs move
the slower u go, the less u bounce and the less ur legs move
theres def a connecton between them

it some how gives ballancing as much you accelerate your speed as you change their elbow angle and change their swing

For balance and to check it with you opposite side of your body.

Why do you move your arms when you run?

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