Just out of curiosity...if all things being equal, how much could a person improve simply by losing weight. Is there a formula that could properly express this.
The numbers I'm working with are
6'3" my height
215 my current weight
23.4 my 50free scy time at nats last april
now my weight at nats was 215 after losing 20lbs over the season. I'm really paying attention to my diet and nutrition and trying to trim down another 10lbs.
Any thoughts???
You might be surprised to see how much you accelerate and decelerate through a stroke cycle.
There could be more intrastroke acceleration with respect to my center of mass than I am perceiving, but such acceleration should serve to increase my kinetic energy (1/2)m*v^2 (hopefully that velocity increase is mainly in the direction I am trying to go) and it seems to me that some of this kinetic energy bleeds off due to drag during periods of the stroke where I am applying little or no force and my center of mass is decelerating. It is difficult for me to visualize separating all the effects, but my intuition tells me that increasing m and keeping all other effect equal, should result in smaller velocity fluctuations throughout the stroke, but interstroke acceleration of the center of mass should be close to zero or even negative.
In typical freestyle the swimmer almost completely stops and accelerates to the top swimming velocity (excluding push) every cycle. ...
I could be missing some effect, but this does not seem right to me. I know when I miss a turn and the velocity of my center of mass drops to near zero, it takes quite a bit of work to get up to speed again. I feel nothing like that effect during regular freestyle. I can visualize parts of the body, especially the hands, having wildly varying velocities throughout the stroke. An accelerometer attached to any given part of my body would detect the superposition of the velocity of my center of mass and the velocity of that body part with respect to my center of mass. But it is not clear to me which is the greater velocity even in the case of an accelerometer attached near my midsection.
I could be missing some effect, but this does not seem right to me.
I agree. Yes, there are big variations in acceleration throughout the stroke cycle, but if your velocity drops close to zero something is wrong.
This is the post from TeamTermin U.S. Masters Swimming Discussion Forums - View Single Post - My freestyle technique, what needs work?
The images show a max velocity of about 2.1 m/s and a min velocity of around 1.5m/s during each stroke.
In typical freestyle the swimmer almost completely stops and accelerates to the top swimming velocity (excluding push) every cycle. I saw this from datalogged swims on software which displayed both video and graphic representation, was very cool (Team Termin). Another interesting point is when your at your slowest velocity other parts of your body are accelerating like your recovery hand and shoulder.
I see the argument against considering mass when accelerating against drag forces. The problem with that is it assumes drag forces (and other forces acting against the forward motion of the swimmer) are equal for both a skinny person and a fat person. I don't think that this is the case. It comes down to whether or not additional bouyancy overcomes and increased cross-section and surface area. I personally don't think it will but the math to back that up isn't something I'm ready to get into.
