“THE PHYSICS OF SWIMMING”
The Physics of Your Body
 Gravity and buoyancy affect your body position in the water.
 It is critical to keep as much body mass as possible forward of the center of
buoyancy, in all 4 strokes.
 Lowering the chin towards the chest and extending the arms outward in
front of the body are adjustments that can be made to correct body posture
and shift body mass.
 Most people’s natural still position in the water is vertical; swimming is
horizontal.
 Spinal alignment from the top of the head to the toes must be achieved in
all strokes.
 The first way to make the body more horizontal is to adjust the head
position.
 In adjusting balance, “pressing the chest” down will result in the hips
going up, dramatically improving body position.
 In adjusting balance, when you put your arms “in front” of your head, your
hips will go up into a horizontal position.
 Horizontal balance in the water is the key ingredient in good swimming.
 The 3 secrets to speed are rhythm, range, and relaxation.
The Physics of Freestyle
 The eyes should be looking down except when breathing.
 Freestyle is swum on the side.
 Sprint freestyle (less than 100 yards) swimmers have less of a body roll.
 Distance freestyle (more than 100 yards) swimmers have more of a body
roll.
 From entry to exit, the hand and arm speed should accelerate to the exit.
 When breathing, the swimmer’s mouth should be ½ out of the water and
only 1 goggle should be out of the water.
 A good freestyle kick should create “whitewater” at the surface.
The Physics of Backstroke
 Backstroke is swum on the side, with the head being stationary; eyes
looking up.
 The hand exits the water with the thumb leading and enters the water with
the little finger “pinky” leading.
 Underwater, the backstroke pull should be with bend elbows.
 Use an underwater dolphin kick off the start wall and off each turn wall.
 A good backstroke kick should create “whitewater” at the surface.
The Physics of Breaststroke
 Most successful variations of any of the 4 stroke.
 Body mass needs to be shifted forward in order to swim “downhill” in each
stroke cycle.
 The stroke timing should be “kick, reach/stretch, and pull.”
 The breaststroke kick starts with the toes turned outward.
 During the majority of the stroke, the eyes should be looking downward at
a 45 degree angle.
 In the breaststroke pull, the elbows stay close to the surface of the water.
The Physics of Butterfly
 Hands go in; chest goes down; hips go up.
 After the start, kick no more than 15 meters/16.4 yards underwater before
you surface on the first stroke.
 Recover with your arms as low as possible; not touching the surface of the
water.
 Look downward and breathe in the ½ inch of air above the water; don’t’
look forward when you breathe.
 Recover with the little finger “pinky” leading the hand forward.
The Physics of Starts
 Focus on the starter’s commands; vocal and whistles.
 Remember light travels fasters than sound; make sure you can see the
strobe light on top of the starting unit.
 In the forward start of the blocks, the hips line up above the toes of the rear
foot on the block.
 The streamline off the blocks should occur in flight prior to the entry into
the water.
 In relay starts, most false starts are caused by the incoming swimmer taking
an extra stroke or “short stroking”; always stretch the last stroke.
The Physics of Turns
 In freestyle turns, the speed of rotation can be increased by accelerating into
the wall and tucking tight in a ball when turning.
 In backstroke turns, stroke count from the backstroke flags to the wall is
critical.
 In both breaststroke and butterfly turns, the swimmer pushes off the wall on
their side and rotates onto their breast before the first arm action.
 In both breaststroke and butterfly turns, the first arm off the wall goes under
water, the second arms goes over the water.