1. General introduction to principle in T,FGeneral introduction to principle in T,F 2. The principle in runningThe principle in running 3. The principle in jumping 4. The principle in throwing Chapter Two The technical principle of Track and Field

Target 1. Knowing the concept of Track and Field technique, The standard of evaluating the Track and Field techniques and the forces effecting the movements of body and material. 2. Knowing how to divide running,jumping and throwing into several phases. Understanding the main factors that decide the results of running, jumping and throwing. 3. Knowing the basic requirement of techniques

1. General introduction to principle in T,F  Concept of Track and Field technique  The standard to evaluating the Tech. Of T.F  Forces that effect on body and equipment

Definition: It is the way of movement that people could run faster,jump higher and throw longer in practice by rationally using themselves ability of organism. The technical principle of Track and Field:It is the analysis and explain about basic regulation and scientific reasons in popular by using related sports theory. Concept of T.F technique

The standard to evaluating the Tech. Of T.F 1.Actual effect: means the player can use sufficiently body’s sport ability and make the biggest function and obtain/gain the best sport effect during doing movements 2.Economical efficiency: means rationally use energy and avoid to used up /consume energy unnecessarily in the condition of done the movement smoothly. without surplus / excess and nervous/intensive movements

2. External force: come from the interaction produced by body or apparatus that interact with the outside A.reaction force of support B.air action force C.friction D.gravity Forces that effect on body and equipment 1. Internal force: means force come from the interaction produced by motor organs of body A. muscle contractive force B.ligament resistance power in or out of joints C. inside friction: Inside muscle tissue

The principle in running  Definition OF Running, period and phase  The fact deciding speed  Technical requirement for each phase

Definition OF Running, period and phas Running is a basic motion formation and a cyclical/periodic movement with single leg support alternating with flight through the coordination of driving and swinging

One period is composed of/formed by two supporting periods and two flight periods. The supporting period: From foot contacting with the ground to leaving the ground. The flight period: From one foot leaving the ground to other foot contacting the ground. （如图） （如图）

period supportingflightsupportingflight phase Right leg Suppor ting forwar d Driving back Swing backSwing forward Left legSwing forward Supporti ng forward Driving back Swing back

The facts are Length of stride and Stride frequency 。 The fact deciding speed speed ＝ Length of stride × Stride frequency （如图）

(1)Length of leg and height 1.Back drive distance (2)driving distance Length of stride (3)Driving angle 2.Distance of flight (1)initial speed (2)Leaving angle (3)Air action 3.Buffer distance (1)Length of leg and height （ 2)Angle of contacting the ground

1. Support period (1) Buffer time (2)Driving time Stride frequency (1)Initial speed 2.Flight period (2)The angle of leg thrust (3) Initial speed

Technical requirement for each phase Start

Technical requirement Once the starting gun is fired,the starting action is initiated by an explosive and almost simultaneous push by the legs and the arms. The back leg and upper body should form a straight line, in turn form an angle about 42-45° with the track surface. In the first two strides, the feet contact the ground behind the vertical projection of the center of gravity, and there is a pronounced forward lean of the body.

Acceleration

Technical requirement The feet are placed below the vertical projection of the center of gravity, allowing quick/ short ground contacts, and the body gradually straight to reach “ tall posture ” at about 20-35m.

Running on the way:

Optimal use of driving forces in the driving phase and force must act in horizontal, there is an elastic strength extension of foot, knee and hips joints. Linear swinging movements of the arms by an active lift of the elbow in the rear swing. Make the duration of the support phase as short as possible. Maximum knee angle in the thrust phase is about 160 degrees. The foot plant as close to the vertical projection of the body’s center of gravity as possible. Knee lift phase, the angle of the lifting knee is around 15 degrees below the horizontal. the lower leg has a active pawing, the leg must move downwards/backwards. Technical requirement

The finish running;

In the last stride, the upper body leans forwards and two arms swing backwards Technical requirement

 Definition and phases of jumping  The factors deciding the result of jumping  Technical requirement of each phases The technical principle of jumping

Jumping is a event that athletes make their bodies move as high/long as possible, they do work by themselves, or with some equipment. Jumping is periodic and none periodic Definition of jumping

请单击图： high jump

请单击图： long jump

请单击上图： triple jump

请单击图： pole vault

The technical phase the movement of body is horizontal ⑴ Run-up phase ： the horizontal movement of body is shifted parabola. 。 ⑵ Take off phase ： parabola phase ⑶ Flight phase ： Landing the ground 。 ⑷ Landing phase ：

The factors deciding the result of jumping ㈠ high jump Formula H= H1+H2+H3 （如图）如图）

it is the height of body’s gravity before the athlete flight It is decided by height of body, length of leg and the posture before lift H1H1

the vertical distance of gravity from flight beginning to the top of flight It is decided by initial speed and the angle of flight H2H2

The vertical distance from gravity to the bar when the body reaching the top It is decided by posture and technique Take off is the key H3H3

Requirement for take off 1.buffer the body by bent the knee, lean the upper body backwards when take off. 2. Stretch the ankle, knee and hips joints 3. Swing leg and two arms swing upwards 4.Short the buffer time by landing fast the angle of parabola is consist of initial speed direction of body and horizontal direction, it is about 50°-65°

Long jump The result L=L1+L2+L3 （如图） （如图）

is the horizontal distance from the projection of gravity before take off to the front of broad. It is decided in the accuracy of take off, height, the length of leg and posture L1L1

is the gravity moves horizontal distance. It is decided in the initial speed of gravity, angle of parabola, the height of gravity and air resistance. L2L2

is the horizontal distance from the projection of gravity before landing to the landing point. It is decided in landing movement and posture. L3L3

The projectile formula: s=v sin2a/g S is decided in initial speed and angle of parabola The rational angle (a) of parabola is 18°-24°

1. Relax, natural, moving stability of gravity 2. The stride and rhythm are stable 3. The rhythm in the last steps is obvious and low the gravity suitably （一） Run-up/ approach Technical requirement for each phase

The task: gain the necessary vertical speed, in order to having initial speed of parabola as large as possible and suitable angle of parabola. The technical stage: touchdown, amortization and extension. （二） Take off

touchdown: lands quickly on the entire sole of the foot of the almost fully extended takeoff leg. The foot should move downwards and backwards in a fast, pawing movement. The take off leg should be slightly bent (to about 165°), the upper truck remains upright extension: the jumper extends the knee and ankle joints of takeoff leg. The upward movement of the arms and raising of the shoulders should be brought to a sudden halt. This transfers momentum from the arms and the shoulders to the body, thus adding height to the jumper.the thigh of jumper’s free leg should be virtually horizontal, the body should remain straight.

（三） Flight (sail, hang and hitch-kick) Sail: the takeoff leg is brought forwards, the upper truck is kept straight in the first part. The knee joint of the free leg is extended and the truck is bent forward at the stage of landing. The striding position: it is a body’s position when the jumper leaves the ground. 。

 Definition and phases of throwing  The factors deciding the throw result  Technical requirement for throwing event The principle in throwing

Definition and phases of throwing Definition : The throwing is a movement event that the thrower uses his ability to cast a fixed equipment as long as possible.

请单击图

1. Preparatory stage; hold on equipment, preparatory posture 2 Preliminary acceleration stage; approach run, slide, rotation 3.Delivery 4.Recovery; body ’ s balance Phases (4)

The formula S=S1+S2+S3 （如图）： （如图） The factors deciding the throw result

; it is the distance from the throwing arc to the projection, decided in height, the length of arm, the location of body and posture. S1S1

; it is the distance from the joint of trajectory to the cross joint, decided in initial speed of trajectory, angle of trajectory and air – action S2S2

S3; it is the horizontal distance from the cross joint to the landing joint S3S3 S=S 1 +S 2 +S 3

The projectile formula: s=v sin2a/g the best angle of trajectory is 45° in theory, because the angle of depression/fall and air-action, the angles of trajectory in throwing events are less than 45°. Shot put is 38°-42 °, Javelin and discus is 30 °-3 5°, Hammer throwing is 42 °-44° 出手角与地斜角演示图

Result is decided in initial speed of trajectory, angle of trajectory The initial speed of trajectory is decided in the size of acceleration during delivery The formula of mechanics F=MA F means force M means quality A means acceleration So F↑--A↑--S↑

Preparatory stage; hold on equipment, preparatory posture --Stable, --Make used of the length of throwing arm --Have a good feeling to the equipment --Could control it Technical requirement for throwing event

Preliminary acceleration stage; approach run, slide, rotatio --Be natural and harmonious/ coordinative --Make used of the size of ground --The acceleration is even and certain rhythm --The balance is good --This stage should connect with delivery closely --Form a good posture of exceeding equipment and have a good condition for the stage of delivery

Delivery --Touching the ground of left leg should be fast and forming support of two legs --Correct order and direction of force --The gravity move from low to high --Have a good left support --Have a fast work and short the working time

Recovery; body’s balance --Low the gravity --Exchange the location of two leg --Change the movement direction of body in order to breaking the rule

1 、 what is the technique ? 2. what is the standard of evaluation ? 3. Explain the facts that effect the internal and external forces 4. Why do we learn the technical principle ？ 5 、 how to divide the phase of run,jump and throw ? 6 、 explain the facts that effect the speed. 4 、 what are the stages of run,jump and throw ? 5 、 what are the requirement for above stages? Homework 退出

Chart of the run To next

Supportingflightsupporting Chart of running periods back

Combination of one stride To next

flight distance drive back distance Buffer distance Combination of one stride back

Combination of the jump result H H2H2 H1H1 H3H3 返回

h1h1 H1H1 h2h2 Sectors of H 1 back

The combination of jump result To next

S1S1 S2S2 L3L3 L2L2 L１L１ Combination of long jump back

The orbin after flight back

A sinple chart of throw To next

Combination of throwing event S2S2 S3S3 S1S1 back

Show of trajectory To next

Height of put Vertical line b 地斜角 b 地斜角 A aA angle A aA angle Landing point The point S （ distance ） back Chart of shot put