MODEL OF BUTTERFLY SWIMMING TECHNIQUE（蝶泳，含图片）

小臭贝

NAMES OF PERIODS & PHASES:

Stroking period
1. Arm pulling phase
2. Arm pushing with leg kick phase

Arm recovery & flying period
3. Arm recovery phase
4. Arm entry with leg kick phase

FULL STROKE CYCLE

AIM of movements High forward speed !

Limiting positions beginning: at the end of leg kick and arms entry
  ending: to the end of leg kick and arms entry

General cognitive assignments:
Avoid unnecessary movements during all phases
Optimum alterations of action and relaxation of muscles during pull and recovery actions
Increase propulsive forces by stroking with arms and kicking with legs
Decrease resistance to the body at all times
Ensure rigid transfer of power to the body from strokes and kicks through locked joints in right timing
Realise aims of movements in each phase but also prepare for the movements in following phase

Co-ordinate good breathing actions with movements as follows:
Combine exhaling with pulling and pushing arm action
Inhaling at the beginning of arm recovery,
Hold the breath during arms entry


STROKING PERIOD

AIM of movements Try to increase forward speed !

Limiting positions beginning: at the end of leg kick and arm entry
  ending: at the end of arm stroke

Parameters:
Forward movement during stroke: 1.0 - 1.3 (metres)
(This parameter indicates how effective is swimmers stroke. It must be half from full cycle stroke length)
Relative stroke speed of hands backward: (-0.8) - (-0.2) (m/sec)
(If arm stroke is effective and rational, then hands horizontal speed component backward during stroking, related to water, must be slow to create body speed forward)

Cognitive assignments:
Make stroke soft at the beginning with acceleration at the end, with good water feeling and low relative hand speed - sticking to water
Move forward as much as possible during stroke period


PHASES:

1. ARM PULL PHASE



AIM of movements Try to increase forward speed !

Limiting positions beginning: at the end of leg kick and arm entry
  ending: at the mid point of arm stroke

Parameters:
Forward speed during arm pull: 1.5 - 1.9 (m/sec)
(This parameter shows efficiency of first part of stroke- pulling)
Hands pulling slip forward -backward 0.30 - 0.03 (m)
(This parameter indicate economical side of that arms pull and quality of feeling of water during first part of stroke)

Requirements for self control:
The arm action at the beginning of pull must be with good catch, aside down, with high elbow position
The leg action during the pull must be quick with overextension of knees
The shoulders and body action during the pull must be relatively high with good overextension of upper part of body
Hands slip during pull must be positive, gliding forward, body moving on the pull
Position of arms at the middle of stroke must be almost vertical, hands in front of shoulder line.


2. ARM PUSH & LEG KICK PHASE

AIM of movements Try to reach maximum forward speed !

Limiting positions beginning: at the mid point of arm stroke
  ending: at the end of arm stroke

Parameters:
Forward speed during push: 2.0 - 2.5 (m/sec)
(This parameter shows efficiency of co-operation work done by strong arms pushing actions as well as by impulsive legs kick same time)
Hands pushing slip backward (-0.50) - (-0.30) (m)
(If hands are slipping too much backward, then it means that arms are working relatively alone, “breaking” water with high power)

Requirements for self control:
The arm push must be long, with elbows close to body and wrists locked
The leg kick during push must be with good transfer of force, impulsive, correct timing for fixing knees and high hip at the end of kick
Keep the body position high, flat and horizontal. Extending chin forward and not rising shoulders too much.
Avoid hands slip through the water - try to stick them

FLYING PERIOD

AIM of movements Try to maintain forward speed !

Limiting positions beginning: at the end of arm stroke
  ending: to the end of next leg kick and arms entry

Parameters:
Forward movement during recovery & entry: 1.0-1.3 (m)
(This parameter indicates how effective is swimmers flight and arms recovery. It must be another half from full cycle stroke length or even longer )
Hand speed during recovery & entry: 4.0-5.0 (m/sec)
(Parameter shows arms recovery speed forward together with body. Too high speed of hands without good forward speed of body, same time, indicate lack of feeling bringing arms forward and momentum from quick arms recovery reacting against good forward mome

Cognitive assignments:
Bring arms forward with body, not too quickly, with flying action
Move forward during that period even more than during stroke