男子仰泳出发技巧

backstroke START TECHNIQUE

NAMES OF PERIODS & PHASES:
1. Reaction & hands release phase
2. Pushing phase
3. Flight phase
Gliding period
4. Entry & gliding phase
5. Underwater kicking phase
Pullout period
6. Pullout phase
7. Swimming after start


AIM of movements. High speed for the beginning of the race !
Limiting positions
beginning:
from the start signal

ending:
at the end of the start actions

General cognitive assignments:
Avoid unnecessary movements during all phases
Prepare for start, follow orders of starter, enter the water, take starting position and be ready for signal
Keep muscles relaxed during gliding and kicking
Decrease resistance during entry, gliding and kicking
Increase propulsive forces during push-off, kicking and pullout
Ensure correct timing of fixing joints for transfer of power during push, kicks and pullout
Inhale after push-off and begin breathing after the finish of start actions
Realise aims of movements in each phase but also prepare for the movements in following phase



PHASES:
1. REACTION & HANDS RELEASE PHASE
AIM of movements. Try to minimise duration !
Limiting positions
beginning:
from the starting signal

ending:
when the hands leave the wall
Parameters:
The duration of reaction & hands release: 0.35- 0.50 (sec)
(This parameter indicate time necessary to prepare and begin pushing action. Parameter indicate not only reaction to signal, but also time spent to all preparation movements before beginning real pushing actions. It is easier to reduce that duration, then pushing time)
Requirements for self control:
Take good body position, hips nearly out of water
Be ready to react with leg push first
Immediately try to move head and shoulders forward
React to the starting signal as quickly as possible
2. PUSHING PHASE

AIM of movements. Try to create maximum pushing power !
Limiting positions
beginning:
when the hands leave the wall

ending:
when the feet leave the wall
Parameters:
The duration of pushing action : 0,20 - 0,12 (sec)
(It indicates pushing power, as well explosive form of push)
Forward speed of head during push: 4,2 - 5,5 (m/sec)
(Head speed forward indicate that not only pushing by legs, but also body and head need to move fast forward to take fly-off position)
Requirements for self control:
Transfer impulsive pushing forces in forward and upward direction
Arms must be brought forward straight, as quick as possible, not too high
Head must move forward; back and hips up,
At the end of push body angle must be diagonal and straight
The duration of pushing action must be short
3. FLIGHT PHASE



AIM of movements. Try to increase the length of flight !
Limiting positions
beginning:
when the feet leave the wall

ending:
when the head enters the water
Parameters:
Forward speed of body during flight : 3.1 - 3.8 (m/sec)
(This is main parameter of successful flight, high flight speed is precondition for good start)
The length of head entry : 2.1 - 2.7 (m)
(Arms usually enter further then head, but if head enter after arms to the same length follow very successful entry of all body)
Requirements for self control:
During flight rise hips very high
Rise legs up and bring feet totally out of water before entry
Hide head between arms before entry
Keep high flight speed
4. ENTRY & GLIDE PHASE




AIM of movements. Try to increase entry speed !
Limiting positions
beginning:
when the head enters the water

ending:
at the beginning of the first leg kick
Parameters:
Forward speed of hands during entry : 3,2 - 3,7 (m/sec)
(High entry speed shows swimmer quality of streamlining and will guarantee continuous high speed for following gliding)
Forward speed of body after entry : 2.2 - 3.0 (m/sec)
(This parameter shows also swimmer hydrodynamic streamline qualities and timing of the first leg kick actions)
Requirements for self control:
Keep head, body and legs very streamlined without splashing legs into water, enter through “one hole"
Make an immediate small dolphin leg kick during entry
Do not loose forward speed immediately after entry
5. UNDERWATER KICKING PHASE



AIM of movements. Try to keep high forward speed !
Limiting positions
beginning:
at the start of the first leg kick

ending:
at the start of the first arm stroke
Parameters:
Forward speed during underwater kicking: 1.75 - 2.0 (m/sec)
(Efficiency of underwater undulation movements and leg kicks)
Duration of gliding with leg kick: 3.0 - 6.0 (sec)
(If speed is high, then duration may be longer, if low then shorter)
Requirements for self control:
Leg action after entry must be with undulating movements with correct force transfer and rhythm
Keep head between the stretched arms during leg kicks
Count optimum number of underwater leg kicks and make them with smaller amplitude at the beginning and bigger at the end
Feel the best duration of kicks to keep high forward speed
Use only effective dolphin legs kicks, instead of flutter kicks
Use movements trajectory of gradual rise to surface!
Decide about length of underwater part according to FINA rules 15m!
6. PULLOUT PHASE



AIM of movements. Try to increase pullout speed!
Limiting positions
beginning:
at the start of the first pullout stroke

ending:
at the end of the second pullout stroke
Parameters:
Forward speed during first stroke: 1.65 - 1.9 (m/sec)
(Parameter indicate efficiency of that first pull)
Forward speed during second stroke: 1.65 - 1.9 (m/sec)
(Parameter indicate efficiency of that second pull)
Requirements for self control:
Timing of the beginning of first pullout stroke, must be in time, at the end of the last dolphin leg kick, and optimum depth of the body - not too deep
Simultaneously with beginning of first arm pull switch over to flutter leg kicks, so that catch of right arm pull is co-ordinated with the right leg kick up, or vice versa
Make first arm pull with extreme forward stretch of other arm
Body must be rising up to the surface at the end of the first arm pull
Timing of the beginning second arm pull must be in time, at the end of first arm push, not too late, avoid extra gliding between strokes
The action of both arm strokes during pullout must be long with good acceleration, fixed elbow positions
Begin breathing actions (exhaling) during first pullout, and keep body position flat
7. SWIMMING AFTER START
AIM of movements. Try to maintain high speed!
Limiting positions
beginning:
at the beginning of the first full stroke cycle after start

ending:
at the end of the first full stroke cycle

Parameters:
Speed of the swimming cycle after start: 1.65 - 1.9 (m/sec)
(High speed indicate good swimming technique after start movements and must be compared with pullout cycles speed before it)
Requirements for self control:
Begin the proper rhythm of swimming and breathing actions with swimming speed according to your individual tactical plan of the race

真酷啊 [s:27]

是我的话,直接沉水里了