# What is the maximum acceleration a human can generate? With which body part?

As I was reading the description on the back of a gaming mouse carton, "50g of acceleration", I was thinking: "A human hand cannot possibly get close to this kind of acceleration!" The ensuing google-search only came up with results as to how much acceleration the human body can withstand, not how much it can produce, so that is why I decided to ask here:

How much acceleration can an average human being generate? (Even if it is just a short burst)

What body part generates the most? How much is it?

How much can the elbow/wrist (whatever is involved in moving a computer mouse) generate?

• I'd vote for snapping your fingers or closing your eyes. Both produce a fast movement really fast. No idea how large the acceleration might be though. – Jens Schauder Jan 26 '14 at 9:03
• I guess one could take measurements from this video: youtube.com/watch?v=isuMXCYhto4 – Jens Schauder Jan 26 '14 at 9:08
• I'd second finger snapping, although blinking makes the eyelid accelerate greatly without a "force acumulator", such as the holder finger used in finger snapping. – Severo Raz Jan 27 '14 at 2:42
• This may be more of a physics question. Do note that the effects of changing direction very quickly can generate more "G" forces at the peak of the direction change. Moving a light weight object like a mouse back and forth quickly would be one reason that the mouse would have to be engineered for excessive G forces. – Berin Loritsch Jan 27 '14 at 16:17
• Baseball - 40 G's - science20.com/science_20/… - Now, if you consider implements, golf drives can exceed 100 g's at impact, hockey is similar, lacrosse sticks, etc. – JohnP Nov 6 '14 at 14:37

As far as I know, the fastest movements and possibly the biggest acceleration are due to eye saccades, that is rapid movements of the eye as it scans the environment. Those are involuntary and have to do with perception.

Wikipedia quotes the speed at 900 degrees/second (2.5 revolutions, for comparison with ADAM). As for acceleration, "Unsupervised clustering method to detect microsaccades" (graph cut-out below) puts peak angular acceleration at cca 7000 degrees/second^2. My arm is ~84 cm long. Earlier this evening, I timed myself doing arm swings at 20 circles/(10 seconds). That's 2 revs/second. With a 84 cm radius, my fingertips were therefore moving 2*[2*pi*(0.84m)]/sec ~ 10 m/s.

• I don't have enough reputation to comment on the other post, so I am leaving a comment here: `7000 deg/sec^2 = = 122 rad/sec^2` - wow! That's really high. The eyeball is tiny, though, so the G-forces are not all that big: angular acceleration alpha `= 7000 deg/s^2 = = 122 rad/sec^2` linear acceleration (tangential to radius) `a = alpha * r` Assume the eyeball has a radius of 1 cm = 0.01 m `a_linear = 122 rad/sec^2 * .01 m = 1.22 m/s^2 ~= 1/8 of G.` – Adam Nov 6 '14 at 18:36
• How about centripetal accelaration? This is highest when the angular speed (omega) is at it's max: `omega = 2.5 revolutions /s = 2*pi*2.5 rad/sec = 15.7 rad/sec` [note radians are actually dimensionless, so the units here are really just per second] `a_centrip = omega^2 *r = 246.7/s^2 * 0.01 m = 2.5 m/sec^2 ~= 1/4 G` So the highest angular acceleration is the eye movement. The highest linear acceleration is probably swinging your arm in a circle. – Adam Nov 6 '14 at 18:37