Freestyle
A
recent study in the Journal of Swimming
Research, concluded with the following statement: The production of force is important; however, resistance increases at a
much greater rate than changes in speed due to propulsive forces. Thus, it is
advocated that swimming actions first should be orientated to minimizing
resistance, and second, to developing propulsion, as long as positions for
minimal resistance are maintained.This theory is widely accepted and appears to
have originated from Prof Boomer, University of Rochester, after whom much of
these stroke concepts are based.It seems essential that the swimmer must
understand the various forms of resistance when practising the physical
mechanics of the stroke. It must be borne in mind that resistance in water
increases as the square of the velocity; and when swimming movements are
exaggerated up, down or laterally to compound this, resistance will increase
dramatically to cube the problem.In every swimming movement you have to consider
body position and balance, resistance and propulsion. When a swimmer creates
waves or wakes, the energy of both originate with the swimmer and this is often
wasted energy and increased resistance.If a swimmer takes a full breath and lies
still in the water, arms at sides, the lower body will sink to from 15 to 90
degrees, depending whether female or male, and body composition. By placing the
arms forward, the balance is changed and the centre of mass moves towards the
centre of air, the chest/lung area.Strokes should be designed to effectively
control the position of the centre of mass, positioning it as close as possible
to the centre of air. In this position the body is much more stable and energy
can now be used for forward motion and not balanced by kicking or pulling.
Although we are talking about freestyle; balance and form/streamlining apply in
all strokes.Having the arms ‘out front’ in freestyle can be explained by the
following: View a freestyler from the side; draw a circle, the centre of which
is at the shoulder. Break the circle into four quadrants, with the water surface
as the dividing line between the top two and the bottom two. To establish the
best profile, both arms should be in the lower front quadrant in each stroke
cycle. Catch up? Yes to a certain
extent, but you will notice that nearly all of the top swimmers favour one side
a bit more than the other in the first quadrant. The subsequent ‘slide’ in
freestyle is becoming more and more evident:
Prof Boomer strongly recommended this technique in Shaping
Skills in Stroke Technique, a presentation given to the World Coaches
Association at the World Clinic in Chicago some years ago. Think of the movement
of pulling as being done by the twisting hip and the body weight on the arm,
which is anchoring the weight of the pull. The resultant movement will turn the
body on to the side for a streamlined position and a more effective pull and
push back, allowing the body to slide on the other side for maximum speed and
distance. Remember: ·
The body spends as much time as possible on its side (45 degrees)
because that is where the resistance is least and the anatomical position aids
the pull. ·
Your head must remain on the end of your spine! Prof Boomer’s advice
in all strokes except backstroke, which means that you don’t lift your head
but keep it in line with your spine. · Your kick must be used for whatever propulsion you need or can get, and not for correcting bad balance or stroke faults.
|