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Old 09-16-2018
sclim sclim is offline
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Join Date: Sep 2012
Posts: 1,499

Originally Posted by Zenturtle View Post
cant you send me some footage (pm ) of your stroke to make talking easier?

constant speed is an important one.
Imagine walking slowly 3km/h and dragging a 100 kg treetrunk through the water.
If you keep that trunk at a constant 3 km/h, you can imagine you dont need so much force to keep it floating forward. A bit of water flowing around it, walking very slow....
Now vary the speed of that treetrunc between 1 and 5 km/h in an alternating manner, whilke keeping the avarage speed the same 3km/h.
You can almost feel your arms getting tired already from pulling that thing forward and releasing it all the time instead of just dragging it forward calmly.
No, you don't need to convince me further -- I fully agree with your logic. In fact, use the infinitesimal calculus approach and imagine the swimmer undergoing variations of, say, + and - 1/4 mph. He may well enjoy the rest while he slows 1/4 mph and benefit from the lack of needing to put out as much power when he decelerates and coasts at his new speed of 2.75 mph. But then he has to accelerate to 3.25mph again (to keep his mean speed at 3.0 mph). This acceleration costs him more power than he saves during his deceleration. Equally dismaying, his energy cost overcoming drag at 3.25 mph (which is proportional to the cube of his velocity in the water), despite the saving at 2.75 mph, will always add up to more than that of the swimmer who doesn't vary his velocity and keeps precisely at 3.0 mph all the time.

Now, to develop the skill and the co-ordination to keep at 3.0 mph all the time without thinking so hard about it that something else screws you say, that's another thing again.

The video thing is particularly awkward in the pool where I spend almost all my time. They have a thing about cameras due to an incident a few years ago. I may try and work something out, maybe. Or at another pool.

Last edited by sclim : 09-16-2018 at 08:41 PM.
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