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1 Chapter 1 : The Rotation Over The Bar In The Fosbury-Flop High Jump Physical Fitness Manual For The U. S. Navy Item Preview Hand spring from thrower's hips with kick lift Figure Back somersault with leg Authors submitted their contribution of the article to the editorial board. Abstract Back swing connections during gymnastics acrobatic series considerably influence technical performance and difficulties, particularly in the back somersault. Five high level male gymnasts age A force plate synchronized with a two dimensional movement analysis system was used to collect kinetic and kinematic data. The backswing connections were different in the take-off angle, linear momentum, vertical velocity and horizontal and vertical displacements. In conclusion, considering that the higher elevation of the centre of mass in the flight phase would allow best performance and lower the risk of falls, particularly when combined to a great angular momentum, this study demonstrated that the optimal connection series was round-off, flic-flac to stretched salto which enabled the best height in the somersault. Analysis of the results suggests that both connections facilitate the performance of single and double or triple backward somersaults with or without rotations around the longitudinal axis. Gymnasts could perform these later while gaining height if they chose the round-off, flic-flac technique or gaining some backward displacement if they choose the round-off, salto tempo. Generally speaking, the somersault results from the coordinated involvement of body parts that is imposed to generate an optimal solution to constraints occurring during the execution whether external constraint such as gravity or internal ones such as the relative orientation of body segments and the inertial characteristics of these segments. In gymnastics, the most difficult acrobatic movements on the floor depend upon the efficient execution of the transitional skills, i. The backward take-off initiates the linear and rotational impulses for somersaults with various body positions tucked, picked, straight or stretched. The aim of the take-off that precedes a stretched backward somersault on the floor routine is the optimization of the associated variables: In artistic gymnastics, the transition skills are decisive to successfully and safely perform acrobatic elements. Gravity is the only force acting on the gymnast during the flight period of a somersault. The main consequence is that the angular momentum is constant between the take-off and landing based on the principle of conservation of angular momentum. Material and Methods Participants Five elite male gymnasts age The inclusion criteria were: After being informed about the procedures, methods, benefits and possible risks involved in the study, each subject reviewed and signed a consent form to participate in the study. The experimental protocol was performed in accordance with the Declaration of Helsinki for human experimentation and was approved by the university of Manouba ethical committee. Measurements This research was a simultaneous dual approach study kinematic and dynamic of two acrobatic backswing connection series: These two connections were different in the arms and snap down actions: Maximal vertical force Fy max and maximal rate of force development RFD max were analysed following the data acquisition. Body markers were digitized using a video based data analysis system SkillSpector 1. The indirect kinetic data: Procedures Testing was carried out in the Gymnasium of the Olympic City within a 3-day period, starting at 4: The force plate was integrated into the extremity of the acrobatic track and synchronized with the two cameras. The first camera was placed in front at 3m and the second sideways at 7m from the acrobatic track. During all procedures, the participants wore only shorts and gymnastic sneakers. A minute warm-up, based on light jogging, stretching and several easy acrobatic elements was allowed before testing. Each gymnast started in a standing position at the start of the acrobatic track. He was required to randomly perform one of the acrobatic series at a precise signal. The execution of each acrobatic series was separated by two minutes of recovery and a five-minute rest period between the two techniques. Only the best somersault of each acrobatic series was retained for the comparative study. An experienced international competition judge marked all trials and helped to choose the best somersaults to be considered for analysis. The following scale was used for the interpretation of d z: The normality of distribution estimated by the Kolmogorov-Smirnov test was not acceptable for all variables. Therefore, the non-parametric Wilcoxon Rank-sum test was applied to compare the acrobatic series pair-wise. The results were considered significantly different when the probability was less than or equal to 0. Statistical Page 1

2 analyses were performed using the software package SPSS version Results Table 1 shows all the descriptive kinetic and kinematic variables. These were compared between the two acrobatic series and presented in Table 2. The following paragraphs highlight the main findings: Table 1 Descriptive statistic of backswing connections Variables. Page 2

3 Chapter 2 : F/X : More 'Gump' Effects: The Gary Sinise Illusion - latimes Chris Jericho's moves 1 - arm drag 2 - arm bar 3 - moss cover three handled family grudunzle 4 - arm bar 5 - back breaker 6 - body slam. The And Meters: Track Coach is very pleased to present this outstanding work on the high jump, a piece that will be of great benefit to anyone coaching the event. The focus on correcting technical problems should have an immediate impact on the coach. Do not be deceived by the title. A high jump can be broken down into three phases: After takeoff, the center of gravity e. The parabola should reach the maximum possible peak height. In a Fosbury-fIop, the rotation consists of a "twist" a rotation around the longitudinal axis of the body which turns the back of the athlete toward the bar, and a "somersault" a rotation around a transverse axis which makes the shoulders go down and the knees go up Dapena, The combination of these two motions produces a twisting somersault rotation which leads to a face-up layout position at the peak of the jump. Combined with an arched configuration of the body, this position allows the athlete to clear a bar set at a height that is near the maximum height reached by the c. Some high jumpers are unable to perform the necessary somersault and! This can limit the effectiveness of the bar clearance and therefore the result of the jump. The most frequent problems in the rotation of a Fosbury-fIop high jump are due to insufficient amounts of somersault or twist rotation after takeoff. An insufficient amount of somersault rotation sometimes misleadingly described as "stalling" makes it difficult for the legs to clear the bar; an insufficient amount of twist rotation produces a tilted position of the athlete at the peak of the jump, with the hip of the lead leg lower than the hip of the takeoff leg. To a great extent, the rotation over the bar is produced, by the angular momentum of the athlete. To understand the nature of the problems that can occur in the bar clearance, it is necessary to have "a clear concept of what angular momentum is, and how it affects the rotation. In general terms, the larger the angular momentum, the faster the rotation. High jumpers need to have the right amount of angular momentum in order to perform in the air the rotations necessary for a proper bar clearance. Angular momentum cannot be changed after the athlete leaves the ground; the athlete has to obtain the angular momentum during the takeoff phase, through the forces that the takeoff foot makes on the ground. As mentioned before, the airborne motions of a Fosbury-flop can be described roughly as a twisting somersault. We will look first at the somersault rotation, and later at the twist. Forward somersaulting angular momentum During the takeoff phase, the athlete produces angular momentum about a horizontal axis perpendicular to the final direction of the run-up see Figure 1a and the sequence at the top of Figure 2. This is called the forward somersaulting angular momentum HF. In the last step of the run-up, the high jumper thrusts the hips forward, and this makes the trunk have a backward lean at the start of the takeoff phase i. Then the trunk rotates forward during the takeoff phase, and is vertical at the instant that the foot leaves the ground. The angular momentum obtained by the athlete is related to the tilt angles of the trunk at the start and at the end of the takeoff phase: A larger change in the trunk tilt from a backward position toward the vertical during the takeoff phase is associated with the generation of a larger amount of for- ward somersaulting angular momentum Dapena, The forward somersaulting angular momentum can also be affected by the actions of the arms and of the lead leg. Wide swings of the arms and of the lead leg during the takeoff phase can help the athlete to produce a high parabola. However, in a view from the side top sequence in Figure 3 they also imply strong backward clockwise rotations of these limbs, which can reduce the total forward somersaulting angular momentum of the body. To decrease this problem, some high jumpers turn their back toward the bar in the last step of the run-up, and then swing the arms diagonally forward and away from the bar during the takeoff phase see Figure 4. Since this diagonal arm swing is not a perfect backward rotation, it interferes less with the generation of forward somersaulting angular momentum. Lateral somersaulting angular momentum During the takeoff phase, angular momentum is also produced about a horizontal axis in line with the final direction of the run-up see Figure 1b and the bottom sequence in Figure 2. This is called the lateral somersaulting angular momentum HL. In a rear view of an athlete who takes off from the left leg, this angular momentum component produces a clockwise rotation. If the jumper used a straight run-up, in a rear view the athlete would Page 3

4 be upright at touchdown and leaning markedly toward the bar at the end of the takeoff phase. Since a leaning position at the end of the takeoff would result in the generation of less lift, the production of angular momentum would thus cause a reduction in the maximum height reached by the c. However, if the athlete uses a curved run-up, the initial lean of the athlete to the left at the start of the takeoff phase will allow the athlete to be upright or only slightly past the vertical at the end of the takeoff see Figure 1b and the bottom sequence in Figure 2. Therefore the curved run- up, together with the generation of lateral somersaulting angular momentum, contributes to the generation of more lift than if a straight run-up were used. Large changes from left to right in the tilt angle of the trunk during the takeoff phase are generally associated with larger amounts of lateral somersaulting angular momentum at the end of the takeoff see Dapena, The bottom sequence in Figure 4 shows that in an athlete who takes off from the left leg a diagonal arm swing is associated with a clockwise motion of the arms in a view from the back. Therefore, a diagonal arm action not only interferes less with the generation of forward somersaulting angular momentum, but also contributes more to the generation of lateral somersaulting angular momentum. High jumpers usually have a larger amount of the lateral component of somersaulting angular momentum than of the forward component. The sum of these two components adds up to the required total or "resultant" somersaulting angular momentum, Hs Figure 1e. In general, athletes with more angular momentum tend to rotate faster. Female high jumpers tend to acquire more angular momentum than male high jumpers. These actions create angular momentum about a vertical axis. This is called the twisting angular momentum, HT, and most high jumpers have no difficulty obtaining an appropriate amount of HT. However, we will see later that the actions that the athlete makes in the air, as well as other factors, can also significantly affect whether the high jumper will be perfectly face-up at the peak of the jump, or tilted with one hip lower than the other. How- ever, this does not mean that the paths of all parts of the body are determined. What cannot be changed is the path of the point that represents the average position of all the body parts the e. Using this principle, after the shoulders pass over the bar the high jumper can raise the hips by lowering the head and the legs. For a given height of the e. This is the reason for the typical arched position on top of the bar. To a great extent, the rotation of the high jumper in the air is also determined once the takeoff phase is completed, because the angular momentum of the athlete cannot be changed in the air. However, some alterations of the rotation are still possible. By slowing down the rotations of some parts of the body, other parts of the body will speed up as a compensation, and vice versa. This is called rotational action and reaction. The principles of action and reaction just described both for translation and rotation result in the typical arching and un-arching actions of high jumpers over the bar: As the body unarches, the legs go up, but the hips go down. Therefore, timing is critical. If the body un-arches too late, the calves will knock the bar down; if the body un- arches too early, the athlete will "sit" on the bar and will also knock it down. Another way in which rotation can be changed after takeoff is by altering the "moment of inertia" of the body. The moment of inertia you should think of it as a single long word, "moment-of-inertia" is a number that indicates whether the various parts that make up the body are close to the axis of rotation or far from it. When many parts of the body are far from the axis of rotation, the moment of inertia of the body is large, and this decreases the speed of turning about the axis of rotation. Conversely, if most parts of the body are kept close to the axis of rotation, the moment of inertia is small, and the speed of rotation increases. This is what happens to figure skaters in a view from overhead when they spin: As they bring their arms closer to the vertical axis of rotation, they spin faster about the vertical axis. In high jumping, rotation about a horizontal axis parallel to the bar i. The jumps shown in Figures 5b and 5c both had the same amount of somersaulting angular momentum. However, the athlete in Figure 5c somersaulted faster: It was achieved mainly through a greater flexion of the knees. The technique used by the athlete in Figure 5c can be very helpful for high jumpers with small or moderate amounts of somersaulting angular momentum. In both jumps shown in Figures 5b and 5c the athlete had the same amount of angular momentum, the center of gravity reached the same peak height, and the bar was set at the same height. In the rare cases in which a high jumper has a very large amount of angular momentum, the technique shown in Figure 5c could be a liability, because it might accelerate the rotation so much that the shoulders will hit the bar on the way up. For athletes with a very large amount of angular momentum, it will be better to keep the legs more extended on the way up to the bar, Page 4

5 following the body configuration pattern shown in Figure 5b. This will temporarily slow down the backward somersault, and thus will help to prevent the athlete from hitting the bar with the shoulders on the way up to the bar. Of course, the athlete will still need to arch and un-arch with good timing over the bar. But it was also mentioned that other factors could affect whether the jumper would be perfectly face-up at the peak of the jump Figure 6a, or tilted to one side with one hip lower than the other Figure 6b. One of the most important of these factors is the proportion between the sizes of the forward and lateral components of the somersaulting angular momentum. Figure 7 shows sketches of a hypothetical high jumper at the end of the takeoff phase and after three pure somersault rotations in different directions with no twist, all viewed from overhead. It is very unusual for high jumpers to have only lateral or forward somersaulting angular momentum, but many jumpers have much larger amounts of one than of the other. The example shows that jumpers with particularly large amounts of forward somersaulting angular momentum and small amounts of lateral somersaulting angular momentum will need to twist more in the air in order to be face up at the peak of the jump. Otherwise, the body will be tilted, with the hip of the lead leg lower than the hip of the takeoff leg. Conversely, jumpers with particularly large amounts of lateral somersaulting angular momentum and small amounts of forward somersaulting angular momentum will need to twist less in the air than other jumpers in order to be perfectly face up at the peak of the jump. Otherwise, the body will be tilted, with the hip of the take- off leg lower than the hip of the lead leg. This last problem does not occur very often. Another point that we have to take into account for the understanding of the twist rotation is that, while the twisting component of angular momentum RT is a major factor in the generation of the twist rotation, it is generally not enough to produce by itself the necessary face-up position on top of the bar. In addition, the athlete also needs to use rotational action and reaction about the longitudinal axis of the body to increase the amount of twist rotation that occurs in the air. Rotational action and reaction is sometimes called "catting" because cats dropped in an upside-down position with no angular momentum use a mechanism of this kind to land on their feet. It is difficult to see the amount of twist rotation that occurs through catting in a high jump, because it is obscured by the simultaneous somersault and twist rotations produced by the angular momentum. If we could "hide" the somersault and twist rotations produced by the angular momentum, we would be able to isolate the catting rotation, and see it clearly. To achieve that, we would need to look at the high jumper from the viewpoint of a rotating camera. The camera would also need to twist with the athlete, but just fast enough to keep up with the portion of the twist rotation produced alone by the twisting component of angular momentum. It is impossible to make a real camera rotate in such a way, but we can use a computer to calculate how the jump would have appeared in the images of such a camera if it had existed. This is what is shown in Figure 8. The sequence in Figure 8 covers the period between takeoff and the peak of the jump, and progresses from left to right. All the images are viewed from a direction aligned with the longitudinal axis of the athlete. The head is the part of the athlete nearest to the "camera". Page 5

6 Chapter 3 : The man of 1, holds, Chris Jericho LIST OF ALL 1, INSIDE!!! IGN Boards Back somersault with leg Figure Two-hand chest push 90 Figure II. Hand-lock grip 94 Figure III. Jelly-fish float â shallow water 26 Figure 2. Jelly-fish float â deep water â underwater view 26 Figure 3. Float on back â underwater view 26 Figure 4. Back float â start in shallow water 27 Figure 5. Back float â legs up and arms out 27 Figure 6. Back float â arms and legs outstretched 27 Figure 7. Balanced float â deep water â underwater view 28 Figure 8. Vertical float â deep water â underwater view 29 Figure 9. Horizontal float â deep water â underwater view 29 Figure Treading and sculling â frog kick â underwater view 30 Figure Treading and sculling â scissors kick â underwater view 30 Figure Treading and sculling â bicycle-pedal kick â underwater view 31 Figures 13, 14, 15, Human stroke land drill series 32 Figures 17, 18, 19, Side stroke land drill series 33 Figures 21, 22, 23, Elementary back stroke land drill series 34 Figure Back stroke â legs up â arms recovered 35 Figure Back stroke â legs apart â arms out 35 Figure Back stoke â glide 35 Figures 28, 29, 30, Breast stroke land drill series 36 Figure Breast stroke â glide â underwater view 36 Figure Breast stroke â semivertical â underwater view 37 Figure Resting back stroke â underwater view 37 Figure Human stroke â underwater view 37 Figure Side stroke â glide â underwater view 37 Figure High semivertical breast stroke 37 Figure Indoor installation for abandoning ship drills 38 Figure Outdoor installation for abandoning ship drills 40 Figure Jumping from low level with jackets 42 Figure Jumping from high levels with jackets 43 Figure Abandoning ship drill 45 Figure Jumping and descending lines into water 46 Figure Jumping into water with rubber life-saving suits 46 Figure Life rafts for indoor drill 46 Figure Trouser inflation â a satisfactory float 47 Figure Grasping waist of trousers for inflation 47 Figure Flipping pants for inflation 47 Figure Jumping with trousers for Inflation 47 Figure Rear approach 48 Figure Front surface approach 48 Figure Underwater approach â underwater view 49 Figure Chin pull 50 Figure Hair carry 50 Figure Collar carry 51 Figure Cross chest carry 51 Figure Head carry 51 Figure Block and carry â underwater view 52 Figure Cross chest carry â underwater view 52 Figure Head carry â underwater view 52 Figure Ring buoy tow 53 Figure Tow by inflated trousers 53 Figure Plank tow or push 53 Figure Plank or debris tow 53 Figure Break for front head hold first method 53 Figure Break for front head hold second method 54 Figure Break for rear head hold 54 Figure Break for double grip on one wrist 55 Chapter VI. Early morning calisthenics 56 Figure B. Push-ups 57 Figure C. Deep knee bends 57 Figure D. Back stretcher 57 Figure I. Early morning running 65 Figure 2. Good form in running 66 Figure 3. Obstacle course â cargo nets 66 Figure 4. Obstacle course layout 67 Figure 5. Obstacle course â cargo nets over the side 67 Figure 6. Obstacle course layout 68 Figure 7. Obstacle course â horizontal lines 69 Figure 8. Mass boxing instruction 70 Figure B. Shadow boxing 71 Figure 1 a. Proper alignment of fist 72 Figure 1 b. Front view of fist 72 Figure 1 c. Straight view of fists 72 Figure 2 a. Proper stance or boxing position 73 Figure 2 b. Front view boxing position 73 Figure 3. Left jab or straight left to head 74 Figure 4. Straight left to body 74 Figure 5. Left hook to head 74 Figure 6. Left hook to body 74 Figure 7. Left uppercut to body 76 Figure 8. Straight right to head 76 Figure 9. Straight right to body 76 Figure Right swing to head 76 Figure Right uppercut to body 79 Figure Right uppercut to jaw 79 Figure Right cross counter 79 Figure Blocking straight left to head 79 Figure Blocking left hook to head 80 Figure Blocking left hook to body 80 Figure Blocking straight right to head 80 Figure Blocking right to body 80 Chapter IX. Wrestling holds 83 Figure 1 a. Front waist or grizzly hold 85 Figure 1 e. Tackling an opponent leg dive 86 F gure 1 f. Arm lock straight arm 86 Figure 1 g. Head and hip lock or cross throw 86 Figure 1 i. Flying mare 87 Figure 1 j. Hammer lock with half Nelson 87 Figure 1 l. Three-quarter Nelson 88 Figure 1 m. Straight arm 88 Figure 1 n. Page 6