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az native
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Combining Feed and Hands Power

04/18/2012 5:15 AM

Dear all. I have an idea for an inflated boat, that should be propelled by feet, my friend asked me why wouldn't I use hands power as well, combining the feet muscles with those of the hands which are free?

I answered him that as much as I know, the total power that we can use, is limited by our fitness-the ability ouf the heart-lungs system! Rather than by feet muscles, which are stronger compared to the hands and consume much more blood!

But after thinking, I thought that probably, if the work would be done not only by the feet muscles, but by the upper body muscles- hand and chest muscles would join the effort,then the heart's strain on the blood vesels of the working limbs would be devided ,so the hydrodynamic resistance, would decrease and allow a higher output.

Is this calculation correct?
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SolarEagle
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#1

Re: combining feed and hands power

04/18/2012 5:43 AM

The question can be answered by swimming....Try it with just legs, then just arms, then together....

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szwasta
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#11
In reply to #1

Re: combining feed and hands power

04/19/2012 8:17 AM

And to inflate the boat, just inhale

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JohnDG
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#2

Re: combining feed and hands power

04/18/2012 5:50 AM

Watch how these guys are rowing <click here>. It's a whole-body effort.

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az native
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#4
In reply to #2

Re: combining feed and hands power

04/18/2012 9:12 AM

The question is not if feet muscles can add power to hand [arms] muscles, this is obvious!

The question is vice versa!
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JohnDG
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#5
In reply to #4

Re: combining feed and hands power

04/18/2012 10:49 AM

The answer to that is also obvious

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ky
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#12
In reply to #4

Re: combining feed and hands power

04/19/2012 8:19 PM

Maybe you could show the machine you are using? It seems you have something special/new to present.

John has concluded that the whole body will be involved and that will be the case whatever you have come up with, never mind the vice versa.

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phoenix911
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#3

Re: Combining Feed and Hands Power

04/18/2012 9:02 AM

but now, who needs a boat.

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WJMFIRE
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#7
In reply to #3

Re: Combining Feed and Hands Power

04/18/2012 2:28 PM

CR4 ADMIN: Deleted Post

Inappropriate Image: This post (or part of this post) was deleted because it included an inappropriate image that violates the CR4 Rules of Conduct.

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WJMFIRE
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#8
In reply to #7

Re: Combining Feed and Hands Power

04/18/2012 4:03 PM

Wow, that didn't seem inappropriate to me. Sorry.

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phoenix911
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#9
In reply to #8

Re: Combining Feed and Hands Power

04/18/2012 4:07 PM

Thats ok, I just didn't know how to respond.

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SolarEagle
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#6

Re: Combining Feed and Hands Power

04/18/2012 12:38 PM

This is the hot design...

Greg Kolodziejzyk setting a new human powered boat record for 24 hours, pedalling 173.76 km.(as he prepares for the first human powered crossing of the Atlantic ocean)...2007

http://www.gizmag.com/go/7402/

http://www.gizmag.com/pedal-the-ocean-project/13996/

from 2010...

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marcot
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#10
In reply to #6

Re: Combining Feed and Hands Power

04/19/2012 7:52 AM

He can always push on his knees to use the arm's energy.

While the available energy of an athlete on a long journey is limited (mostly) by his stored fat/sugar and the rate of transfer of food's energy, it makes sense that using more muscle to do the work will give you an advantage in the short term. In the long term, if the legs can burn all the energy that he can extract from the food, the arms will not add more as the body will get the storage from there too (even the muscular mass).

This is why, you may not want to add weight and complexity to his boat by adding some harm powered contraption. Use what is already there.

On the other hand, does he need a short extra push during storms or running away from a large boat? In this case, the arm might help. Also, if the arm pumping system is totally independent, it might add safety in case of failure of the main drive.

This is a difficult decision to make...

Good luck.

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PWSlack
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#13

Re: Combining Feed and Hands Power

04/25/2012 11:38 AM

The type of boat is called a "pedalo". There are tens of thousands of images of them on the 'web.

A sports-fit pedal cyclist can sustain around 1/6hp/125W for extended periods, such output including arm power.

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Users who posted comments:

az native (1); JohnDG (2); ky (1); marcot (1); phoenix911 (2); PWSlack (1); SolarEagle (2); szwasta (1); WJMFIRE (2)

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