What are the optimal biomechanical principles of long jump?
Colleague's E-mail is Invalid. Your message has been successfully sent to your colleague. Save my selection. Address for correspondence: Lee Nolan, Ph. The purpose of this study was to investigate whether female lower-limb amputees conform to the established long-jump model and to compare the kinematics of the approach and take-off phases for elite female transfemoral and transtibial amputee long jumpers.
Eight female transfemoral and nine female transtibial amputee athletes were videotaped sagittal plane movements at 50 Hz from third-to-last step to take-off during the Paralympic Games long-jump finals. After digitizing and reconstruction of 2D coordinates, key variables were calculated at each stride and during contact with the take-off board.
The transfemoral amputees had a consistently higher center of mass height on the last three steps before take-off than the transtibial amputees. However, at touch-down onto the take-off board, they lowered their center of mass excessively so that from touch-down to take-offthey were actually lower than the transtibial amputees. This resulted in a greater negative vertical velocity at touch-down and may have inversely affected their jump performance. Female transtibial athletes conformed to the long-jump model, although adaptations to this technique were displayed.
Biomechanics of the Long-jump
Female transfemoral athletes, however, exhibited no relationship between take-off speed and distance jumped, which may be attributable to their excessive lowering of their center-of-mass height at touch-down onto the take-off board. It is recommended that coaches and athletes proceed with caution when trying to replicate techniques used by able-bodied athletes because adaptations to the constraints of a prosthesis should be considered.
Lower-limb amputees participate in the long-jump event at the highest level in international competition. Advances in prosthetic technology and improvements in training now mean that it is becoming increasingly competitive at elite level, and thus any small improvements in technique could mean the difference between winning and losing.
However, what is known about the long-jump technique currently used by amputees athletes is limited, nor is it known whether the current technique is the most effective. Lower-limb amputee athletes cannot use the same technique as able-bodied athletes because of the absence of active lower-extremity musculature and also because prosthetic limbs have different mechanical properties than intact limbs.
This is further complicated for those athletes with transfemoral amputations who lack active knee-joint extensors to generate propulsive force. Furthermore, absence of neuromuscular control of prosthetic joints may make targeting the take-off board more difficult for transfemoral amputees Thus, further investigation of the technique used by these athletes is required. Much is known about able-bodied long-jump technique, for which several elements seem to be crucial in achieving optimal take-off conditions 5.Colleague's E-mail is Invalid.
Your message has been successfully sent to your colleague. Save my selection. Address correspondence to Krzysztof Mackala, krzysztof. Biomechanical analysis of standing long jump from varying starting positions.
J Strength Cond Res 27 10 : —, —The purpose of this study was a to investigate the effect of the different foot movement placement during take-off and the initial knee joint angle used in standing long jump by the ground reaction forces analysis and 3-dimensional motion analysis BTS SMART motion and b investigate how the jump performances of different foot placement is related to the electromyography EMG activity Noraxon of 3 selected muscle groups m.
Six high caliber sprinters m: Using kinematic and kinetic data, the knee joint angle, the trajectories of center of mass COMmagnitude of take-off peak force, and impulse during take-off phase were calculated. Average standing long jump performances with straddle foot placement were The take-off angles on the COM trajectory also showed differences The contribution EMG activation made by the 6 muscles were almost the same during all phases for the 2 jumps; however, some differences can be found, in either unilateral single leg or sums of both legs bilateral measurements.
A recommendation can be formulated that the contribution of straddle foot placement during take-off can significantly increase the value of power measurement especially when the evaluation requires a complex movement structure with the division on the left and right legs, for example, sprint start from block. The standing long jump is considered a fundamental motor skill for a variety of sports where high-velocity contractions are demanded: sprinting, hurdling and jumping in athletics, football, ski jumping, and some combat sports.
It is also often used as one of the best functional tests to assess explosive power of the lower extremity. The performance length of jump is highly dependent on numerous independent and dependent variables. One is the application of proper jumping technique—motor proficiency, which may influence the achieved results and underestimate the level of explosive power of lower extremities.
Lee and Cheng 12 indicate that the performance of standing long jump may be affected by level of countermovementmaximum joint and muscular strength, and starting posture. Cheng and Chen 5 also claimed that jump distances are insensitive to the starting position, which is determined by angle of knee flexion and posterior position of the trunk at take-off.
Published on Aug 28, Advanced Long Jump technique analysis. SlideShare Explore Search You. Submit Search. Home Explore. Successfully reported this slideshow. We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime. Like this presentation? Why not share! Embed Size px. Start on. Show related SlideShares at end. WordPress Shortcode. RonnieGary Follow. Full Name Comment goes here. Are you sure you want to Yes No.Sunday, 19 June This blog aims to define and discuss the key principles involved in executing an effective long jump.
A number of movement patterns will be identified and compared in order to present one single optimal technique. This distance travelled, from the edge of the board to the closest indentation in the sand to it, is then measured. We have broken down the event of long jump into four main phases: run up, take off, flight and landing. The biomechanical principles specific to these phases will be discussed below. The athlete obtains optimal biomechanical techniques by starting facing the pit, predominately with one foot in front of the other, leaning forward and crouched down slightly preparing to start a sprint Linthorne, displayed in Figure 1.
To maximise velocity, a large force production through the legs and feet is required. Therefore, the athlete needs to accelerate from standing still to a high velocity sprint, applying a force to overcome inertia and gravity to successfully move.
The athlete will accelerate faster as they apply a larger force to push off the ground. This means that as the athlete leans forwards, they push vertically downwards into the ground with a force large enough to overcome inertia, exerting an equal and opposite reaction ground reaction forceaccelerating the athlete forwards when combined with some horizontal force as well Figure 2 Blazevich, These laws are not only relevant in the start position, but continued throughout the whole run-up phase.
A study by Bridgett and Linthorne revealed when run-up and take-off speed increases, there is a positive correlation with the distance jumped shown in Figure 3. Top-speed should be reached quickly as this improves average running speed resulting in greater performance Blazevich, The athlete decides on their run-up distance suited to individual needs to ensure near-maximal speed is reached, generally meters averaging in strides Linthorne, To calculate speed in scalar quantity the change in distance is divided by the change in time of the performance Blazevich, The run-up is performed in a straight line classifying it as rectilinear motion where the athlete moves with positive displacement, distance, and acceleration Blazevich, Athletes need to swing their legs rapidly when sprinting to increase speed.
During running, the hips are the principle aspect of torque production, and the centre of rotation when swinging the legs moment of inertia Blazevich, Torque is the force required to produce angular velocity required for sprinting.
We need this torque, or more simply, power, to overcome inertia of the leg and ensure the athlete continues to move with constant angular velocity Blazevich, To increase torque, the legs need to have a fast swing phase also reducing the loss of speed, and decreasing moment of inertia Blazevich, The leg also needs to be reasonably extended during the swing phase and when landing on the ground.
The quicker the arm swings in a forward motion while being tucked into the body, the more angular momentum it retains Blazevich, which reduces the moment of inertia and radius of gyration further. The backward swing phase needs to be vigorous to accelerate the body forward and upward as this increases running speed.
Therefore, force production needs to be controlled, with correct equal and opposite reactions for optimal technique and performance. Although long jump performance is primarily determined by the athlete's ability to reach a fast horizontal velocity at the end of the run-up, the athlete must also use an appropriate take-off technique to best conserve this momentum.
The distance an athlete jumps is largely determined by the flight distance Hay, and this is determined by the height, speed, and angle of projection of the centre of mass at take-off.
The speed and angle of projection are determined by the combination of horizontal and vertical velocity. If the athlete is able to generate near maximum speed close to the board, the problem long jumpers face is how to best generate vertical velocity from the board.
Adjustments can be made by the athlete when approaching the board to enable vertical velocity to be generated.
The second to last stride before take-off should be longer than the last, where the athlete lowers their body and centre of gravity shown with the slight dip of the hip in Figure 6. Continuing this, the last stride is shorter while maintaining the lowered centre of gravity. These strides are significant, and need to be near-maximal speed with horizontal velocity which has greater kinetic energy utilised and transferred over to the vertical velocity in the take-off and flight Blazevich, ; Linthorne, This is shown in Figure 7 where the centre of mass is represented by the yellow line.
As the athlete extends their leg longer than usual, the centre of mass is not only horizontally changed, but vertically changed as well. The lowering of the centre of mass minimises the downward vertical velocity so as to maximize the effect of the vertical impulse and increase the vertical distance over which the centre of mass is worked. The large touchdown distance has been explained as enabling an increase in the time period during which vertical impulse can be generated, increasing the range of movement through which the hip extensor muscles may work, and placing the leg in a position to enable it to be stretched and store elastic energy which recoils upon release.
In this position the body can pivot over the leg to gain vertical velocity.Skip to search form Skip to main content You are currently offline. Some features of the site may not work correctly.
DOI: Linthorne Published Mathematics. View via Publisher. Save to Library. Create Alert. Launch Research Feed. Share This Paper. Gender differences in takeoff techniques of non-elite Russian long jumpers.HMB278- Long Jump Biomechanics
Catherine Shin, S. Allen, P. Brice Figures and Tables from this paper. Figures and Tables. Citation Type. Has PDF. Publication Type. More Filters. Highly Influenced. Research Feed. Immediate effects of the use of modified take-off boards on the take-off motion of the long jump during training. Step characteristic interaction and asymmetry during the approach phase in long jump.Monday, 22 April What is the optimum approach technique for an athlete in the long-jump?
How can athletes use the principals of biomechanics in the approach phase to increase their jump distance? The long jump is an athletic track and field event where individuals combine speed, strength and agility in order to jump as far as possible in a horizontal direction.
The jump itself is broken down into 4 phases Hay, :. This analysis will be focusing on the first phase: the approach. A long-jumper has three primary objectives to execute during the approach run to maximise their jump distance Hay, : a to generate the highest amount of horizontal velocity as is possible to be used effectively during the take-off; b to set-up the position of the body during the final steps of the approach so that it is in the correct position for take-off; c and to accurately place the foot on the take-off board.
Biomechanics of the long jump
These three components are referred to as velocity, position and accuracy Hay, Speed tells us how fast a thing is moving.
Velocity is determined by dividing the distance covered by the time taken. Acceleration tells us how fast the velocity of something is changing. A number of studies Hay et al. As shown in Figure 1. I deally, a long-jumper reaches their maximum speed during the last few strides of the run-up Hay, Miller and Canterna, Elite male long-jumpers are able to reach speeds of 9.
Figure 1. We are able to run forwards because we apply a backwards force against the ground Blazevich, An athlete is overcoming inertia at the beginning of the approach run in long-jump. Their initial acceleration is generated when they exert a force against the ground with their forward foot. The greater the force exerted, the greater the acceleration away from the ground will be Blazevich, In the approach phase of the long-jump, the athlete wants to generate as much speed as possible through the forces they apply against the ground in order to reach a maximum horizontal velocity which they can then convert to vertical velocity during the take-off to further their jump distance.
To improve running speed we need to understand how to swing our legs more quickly Blazevich, The angular acceleration of the leg is influenced by the amount of torque acting on it and is proportional to the inertia of the leg Blazevich, The legs angular acceleration will be greater if the torque is greater, or the moment of inertia in the leg is decreased.
Furthermore, if the distance between the muscle and the joint center called the moment arm is larger, the amount of torque that can be generated by the leg will be greater. Unfortunately the moment arm cannot be improved through training Blazevich, However, coaches and trainers can work to improve the muscle force of the leg torque which will enable the athlete to generate a greater angular velocity of the leg during sprinting and therefore increase the linear speed of the foot Blazevich, Ultimately, this will make it possible for an athlete to reach their maximum velocity during the approach phase and apply this horizontal velocity to the take-off and flight phase during the jump.
Research suggests that athletes reach their maximum speed 6 seconds after the gun is fired, or around the meters mark of the sprint Hay, Allowing for the fact that long jumpers do not begin their approach in a crouching position and they also need additional strides after attaining their maximum speed to set themselves up for take-off, the optimum approach is around meters Hay This is also governed by the athletes sprinting ability; the faster the athlete, the longer the run-up needs to be to allow them to reach their maximum velocity Hay, Athletes must ensure they allow enough distance in their approach to have time to accelerate to their maximum horizontal velocity so that they can utilise that speed during the jump to attain a larger distance.
A sprinter generates a force against the ground with their foot; this creates an equal and opposite reaction force that moves the body over the ground-see Figure 2.Note: If you make a purchase via any product links on this site, I may earn a small percentage to support my plastic-free mission. And many brands of bottled water are simply filtered tap water.
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