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Exercises Movements, technique & proper execution

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Old 01-21-2008, 09:20 AM   #1
Matt Thomas
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Wall ball

Just a question I had out of curiosity. Does throwing a 20 lb wall ball at a 10 foot target require the same power as throwing a 10 lb wall ball at a 20 foot target?
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Old 01-21-2008, 09:30 AM   #2
Jake Oleander
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Re: Wall ball

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Originally Posted by Matt Thomas View Post
Just a question I had out of curiosity. Does throwing a 20 lb wall ball at a 10 foot target require the same power as throwing a 10 lb wall ball at a 20 foot target?
interesting physics question, i would venture that the 10lb ball 20 feet high might be the harder exercise. its definitely not exactly the same since youre dealing with the acceleration of gravity.
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Old 01-21-2008, 09:39 AM   #3
Darren Zega
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Re: Wall ball

Yes.


The power generated by the exercise is equal to m x h x g:

Where m is the mass moved, h is the height and g is the acceleration due to gravity. If you double one and half the other, the overall power generated stays the same.


That said, you will experience different CNS effects due to having to accelerate your muscles faster. Additionally, the higher ball requires more precision due to the longer distance and will fatigue your stability/precision muscles faster than the 20lb 10ft version will.

Conversely, the 10ft, being a shorter distance, has more room for error and will require less overall aiming and less precise muscle coordination.
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Old 01-21-2008, 09:56 AM   #4
Joey Powell
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Re: Wall ball

the distance the ball is thrown is OVER twice the distance, since you are probably 7.25 ft or so when the ball leaves your hands it is only traveling 2.75 feet or so vertically to hit the target at 10ft.

At 20 feet, the ball must be thrown 12.75ft. With the effect of gravity on the ball, I would venture 10lbs at 20ft is considerably harder and definitely not the same power output. when you factor in time of travel, I bet it is not even close. 10lbs over 20ft, definately more power.

Eeven during the thruster portion of the movement you are only adding 10lbs to your body weight vs 20lbs. So there is no significant power generated on the thruster with 20lbs as compared to 10lbs. Though arm fatigue may be dramatically more noticeable, but that is separate from the pure math of power generated.
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Old 01-21-2008, 10:01 AM   #5
Steven Low
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Re: Wall ball

Joey is correct. If you were standing underground so that your hands would reach "0 ft" then Darren would be more or less right (I think.. not gonna check the physics). But since your hands are around 7-8 feet up it's like 5x more for 20 ft than 10ft regarding the approximate 2.5 vs 12.5 ft difference. This would equate to more or less at least double if not more in the power required.
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Old 01-21-2008, 10:19 AM   #6
Darren Zega
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Re: Wall ball

I just checked my math, Steve's right.


Whoops.


Although, that second half about requiring more effort from the fine motor muscles is still correct, in addition to the excercise being more difficult overall.
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Old 10-21-2008, 02:25 PM   #7
Sean Dunston
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Re: Wall ball

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Originally Posted by Steven Low View Post
Joey is correct. If you were standing underground so that your hands would reach "0 ft" then Darren would be more or less right (I think.. not gonna check the physics). But since your hands are around 7-8 feet up it's like 5x more for 20 ft than 10ft regarding the approximate 2.5 vs 12.5 ft difference. This would equate to more or less at least double if not more in the power required.
Steven-
Hopefully you'll post on the board again.
nice meeting you at the Hopper Challenge - sorry I wasn't more cordial, I think I was in a daze the entire day.

Hey - have you figured out how to start the wallball shot by "standing underground" yet? That would a pretty neat trick!
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Old 10-22-2008, 01:00 PM   #8
Brian Lawyer
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Re: Wall ball

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Originally Posted by Darren Zega View Post
Yes.


The power generated by the exercise is equal to m x h x g:

Where m is the mass moved, h is the height and g is the acceleration due to gravity. If you double one and half the other, the overall power generated stays the same.
Doesn't the fact that the ball is falling from 20 ft versus 10 ft have an effect on the g variable.
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Old 10-22-2008, 01:10 PM   #9
Jake Oleander
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Re: Wall ball

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Originally Posted by Brian Lawyer View Post
Doesn't the fact that the ball is falling from 20 ft versus 10 ft have an effect on the g variable.
this thread is nearly a year old...
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Old 10-22-2008, 02:16 PM   #10
Skylar Cook
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Re: Wall ball

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Originally Posted by Brian Lawyer View Post
Doesn't the fact that the ball is falling from 20 ft versus 10 ft have an effect on the g variable.
No. g = acceleration due to gravity, 9.8m*s^-2. 20 ft vs 10 ft affects h, the height.
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