1 New Message
Digest #4613
Message
Tue Sep 18, 2012 10:32 am (PDT) . Posted by:
"Nick Tatalias" nicktatalias
Hi Ken,
I join this coversation much later. I have read your post with interest and
enjoy the references greatly. I appologise for not participating more but a
work assignment had me in central Africa for all of August and early
September with work pressure and poor connectivity putting pay to much
particiapation.
I managed to see on television Oscar run in both the Olympics and Para
Olympics. I found it interesting that the T43 and T44 racers raced
together but that the single leg amputee was the faster runner beating
Oscar in teh 100m. You have previously mentioned that getting the balance
between normal and blades would confer a disadvantage to the single leg
runner but this was not evident in the shorter sprint events. Do you have
any comments from what you saw in the para olympics.
Regards
Nick Tatalias
Kisanfu
Democratic Republic of Congo
On 7 August 2012 20:35, <CoachJ1@aol.com > wrote:
> **
>
>
> Hi John!
>
>
> >Why? My reasoning was that the calves were as far away from my heart as
> possible which meant longer circulatory routing. As well the blood vessels
> in the calves are smaller, and the distance back to the heart was all
> vertical and again the longest in the body
>
> I'd recommend going Dr. Weyand's lab site:
> _http://smu.edu/education/apw/LocomotorNews.asp_ (
> http://smu.edu/education/apw/LocomotorNews.asp )
>
> Look to your left and scroll down to the lab videos.
>
> There is a clip of Pistorius there, but note the other views as well and
> watch where force is peaking at these higher speeds. By the time the
> athletes appear to be "pushing off," (later phase of stance) force is at
> its
> lowest. For many, this is not intuitive.
>
> As noted in the Weyand/Bundle JAP paper: (Artificial Limbs Do Make
> Artificially Fast Running Speeds Possible):
>
> "The classical literature on terrestrial locomotion established that level
> running is mechanically analogous to a ball bouncing forward along the
> ground. Like a bouncing ball, a runner's mechanical energy and forward
> momentum
> are conserved via recurring exchanges of kinetic and potential energy
> during travel. Runners accomplish this by using their legs in a springlike
> manner to bounce off the ground with each step. On landing, strain energy
> is
> stored as the body's weight and forward speed compress the stance limb and
> forcibly lengthen muscles and tendons. The strain energy stored on landing
> is
> subsequently released via elastic recoil as the limb extends to lift and
> accelerate the body back into the air prior to take off. The conservation
> of
> mechanical energy and forward momentum minimizes the need for propulsive
> force and the input of additional mechanical energy once a runner is up to
> speed."
>
>
> Ken Jakalski
> Lisle HS
> Lisle, Illinois USA
>
> [Non-text portions of this message have been removed]
>
>
>
[Non-text portions of this message have been removed]
I join this coversation much later. I have read your post with interest and
enjoy the references greatly. I appologise for not participating more but a
work assignment had me in central Africa for all of August and early
September with work pressure and poor connectivity putting pay to much
particiapation.
I managed to see on television Oscar run in both the Olympics and Para
Olympics. I found it interesting that the T43 and T44 racers raced
together but that the single leg amputee was the faster runner beating
Oscar in teh 100m. You have previously mentioned that getting the balance
between normal and blades would confer a disadvantage to the single leg
runner but this was not evident in the shorter sprint events. Do you have
any comments from what you saw in the para olympics.
Regards
Nick Tatalias
Kisanfu
Democratic Republic of Congo
On 7 August 2012 20:35, <CoachJ1@aol.
> **
>
>
> Hi John!
>
>
> >Why? My reasoning was that the calves were as far away from my heart as
> possible which meant longer circulatory routing. As well the blood vessels
> in the calves are smaller, and the distance back to the heart was all
> vertical and again the longest in the body
>
> I'd recommend going Dr. Weyand's lab site:
> _http://smu.edu/
> http://smu.edu/
>
> Look to your left and scroll down to the lab videos.
>
> There is a clip of Pistorius there, but note the other views as well and
> watch where force is peaking at these higher speeds. By the time the
> athletes appear to be "pushing off," (later phase of stance) force is at
> its
> lowest. For many, this is not intuitive.
>
> As noted in the Weyand/Bundle JAP paper: (Artificial Limbs Do Make
> Artificially Fast Running Speeds Possible):
>
> "The classical literature on terrestrial locomotion established that level
> running is mechanically analogous to a ball bouncing forward along the
> ground. Like a bouncing ball, a runner's mechanical energy and forward
> momentum
> are conserved via recurring exchanges of kinetic and potential energy
> during travel. Runners accomplish this by using their legs in a springlike
> manner to bounce off the ground with each step. On landing, strain energy
> is
> stored as the body's weight and forward speed compress the stance limb and
> forcibly lengthen muscles and tendons. The strain energy stored on landing
> is
> subsequently released via elastic recoil as the limb extends to lift and
> accelerate the body back into the air prior to take off. The conservation
> of
> mechanical energy and forward momentum minimizes the need for propulsive
> force and the input of additional mechanical energy once a runner is up to
> speed."
>
>
> Ken Jakalski
> Lisle HS
> Lisle, Illinois USA
>
> [Non-text portions of this message have been removed]
>
>
>
[Non-text portions of this message have been removed]
GROUP FOOTER MESSAGE
Modify/cancel your subscription at:
http://groups.yahoo.com/mygroups
Sign all letters with full name & city of residence if you
wish them to be published!
http://groups.yahoo.com/mygroups
Sign all letters with full name & city of residence if you
wish them to be published!
No comments:
Post a Comment
Finish Reading ? Make Your Comment Now..!