[Show abstract][Hide abstract] ABSTRACT: The purpose of this study was to examine the effect of the timing of the pole plant during the stance phase of the jump on the energy level of the vaulter/pole system at take-off for a special pole vault take-off exercise (Jagodin). We hypothesised that an earlier pole plant would increase the pole energy at take-off compared to the energy decrease of the vaulter during the jump and plant complex and so lead to a higher total energy of the vaulter/pole system at take-off. Six male pole vaulters experienced three Jagodins each with different pole plant time building three groups of vaults (early, intermediate, late pole plant). Kinematic data of vaulter and pole were recorded, as were ground reaction forces measured at the end of the pole under the planting box and under the take-off foot. These measurements allowed the energy exchange between the vaulter and pole to be determined. We found neither statistical significant differences in the mechanical energy level of the vaulter/pole system during take-off between the three groups nor a relationship between the timing of the pole plant and the energy level of the vaulter-pole system during take-off. We conclude that although the timing of the pole plant influences the interactions between the vaulter, the pole, and the ground, it does not affect the athlete's performance. Although a late pole plant decreases the loss of energy by the vaulter during the take-off, this is counterbalanced by a decrease in the energy stored in the pole at take-off.
Journal of Biomechanics 04/2012; 45(9):1625-31. DOI:10.1016/j.jbiomech.2012.03.031 · 2.75 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The purpose of this study was to analyze the reproducibility of kinematic, dynamometric and derived mechanical energy parameters in the pole vault as a main precondition for the practical applicability of the concept of energy exchange in the pole vault. A total of 46 vaults of six experienced vaulters were analyzed. On the basis of 3D kinematic data of the athlete and the pole and ground reaction forces measured at the end of the pole in the planting box the reproducibility of parameters that describe the energy transfer into the pole and the energy exchange between the athlete and the pole during the vault was proofed. Intraclass correlation, mean root mean square and the coefficient of variance were determined, additionally the Wilcoxon Test was applied. Parameters of the athlete's 3D total mechanical energy, e.g. initial energy and final energy, and the pole energy (maximum pole energy, energy of the pole due to compressive force and bending moment) were highly reproducible. The distribution of the energy transferred into the pole due to compressive force and bending moment, the same as the energy gain of the vaulter-pole system during the vault, which indicates the strategy of interacting with the pole, were also reproducible. With this the concept of energy exchange in the pole vault can be used to analyze the impact of training interventions, changes in movement pattern respectively, on the vaulters performance during different phases of the vault. The analysis of one trial of an athlete should be sufficient to identify changes in the athlete's interaction with the elastic pole.
Journal of Biomechanics 02/2006; 39(8):1464-71. DOI:10.1016/j.jbiomech.2005.03.027 · 2.75 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The purposes of this study were: (a) to examine the interactions between the athlete and the pole and the possibility for the athlete to take advantage of the pole's elasticity by means of muscular work and (b) to develop performance criteria during the interaction between the athlete and the pole in pole vaulting. Six athletes performed 4-11 trials each, at 90% of their respective personal best performance. All trials were recorded using four synchronized, genlocked video cameras operating at 50 Hz. The ground reaction forces exerted on the bottom of the pole were measured using a planting box fixed on a force plate (1000 Hz). The interaction between athlete and pole may be split into two parts. During the first part, energy is transferred into the pole and the total energy of the athlete decreases. The difference between the energy decrease of the athlete and the pole energy is an indicator of the energy produced by the athletes by means of muscular work (criterion 1). During the second part of the interaction, energy is transferred back to the athlete and the total energy of the athlete increases. The difference between the returned pole energy and the amount of energy increase of the athlete defines criterion 2. In general, the function of the pole during the interaction is: (a) store part of the kinetic energy that the athlete achieved during the run up as strain energy and convert this strain energy into potential energy of the athlete, (b) allow the active system (athlete) to produce muscular work to increase the total energy potential.
Journal of Biomechanics 10/2004; 37(9):1353-60. DOI:10.1016/j.jbiomech.2003.12.039 · 2.75 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to identify differences between elite male and female pole vaulters in terms of their mechanical energy and angular momentum. The vaulter's total mechanical energy and angular momentum were calculated from the three-dimensional kinematic data of the pole vault finals at the Sydney 2000 Olympic Games. The development of total, kinetic and potential energy showed similar characteristics for men and women. The initial energy of the vault, the energy at maximum pole bend position and the final energy were significantly higher for male athletes (P <0.05), while the energy gain produced by the athletes during the vault showed no significant differences (male vaulters 5.88 +/- 1.02 J.kg(-1), female vaulters 5.74 +/- 1.63 J.kg(-1)). Time-related parameters relating to pole bending and recoiling also showed no significant differences (P <0.05). In contrast to the male vaulters, the female vaulters did not show a free upward flight phase. The angular momentum was significantly higher for the female vaulters during the initial pole bend and during the bar clearance (P <0.05). We conclude that the pole vaulting technique of female elite athletes is not a projection of the technique of male elite vaulters at a lower jump height, but rather a different way of jumping and interacting with the elastic pole. The current technique of elite female pole vaulters still has potential for further improvement.
[Show abstract][Hide abstract] ABSTRACT: The purposes of this study are (a) to examine the effects of contact time manipulation on jump parameters and (b) to examine the interaction between starting height changes and contact time changes on important jump parameters. Fifteen male athletes performed a series of drop jumps from heights of 20, 40, and 60 cm. The instructions given to the subjects were (a) "jump as high as you can" and (b) "jump high a little faster than your previous jump." Jumps were performed at each height until the athlete could not achieve a shorter ground contact time. The data were divided into 5 groups where group 1 was made up of the longest ground contact times of each athlete and groups 2-4 were composed of progressively shorter contact times, with group 5 having the shortest contact times. The jumps of group 3 produced the highest maximum and mean mechanical power (p <0.05) during the positive phase of the drop jumps regardless of starting jump height. The vertical takeoff velocities for the first 3 groups did not show significant (p < 0.05) differences. These results indicate that the manipulation of jump technique plays larger role than jump height in the manipulation of important jump parameters.
The Journal of Strength and Conditioning Research 08/2004; 18(3):561-6. DOI:10.1519/1533-4287(2004)18<561:TEODJS>2.0.CO;2 · 2.08 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The purposes of this study are: a) to examine the possibility of influencing the leg stiffness through instructions given to the subjects and b) to determine the effect of the leg stiffness on the mechanical power and take-off velocity during the drop jumps. A total of 15 athletes performed a series of drop jumps from heights of 20, 40 and 60 cm. The instructions given to the subjects were a) "jump as high as you can" and b) "jump high a little faster than your previous jump". The jumps were performed at each height until the athlete could not achieve a shorter ground contact time. The ground reaction forces were measured using a "Kistler" force plate (1000 Hz). The athletes body positions were recorded using a high speed (250 Hz) video camera. EMG was used to measure muscle activity in five leg muscles. The data was divided into 5 groups where group 1 was made up of the longest ground contact times of each athlete and group 5 the shortest. The leg and ankle stiffness values were higher when the contact times were shorter. This means that by influencing contact time through verbal instructions it is possible to control leg stiffness. Maximum center of mass take-off velocity the can be achieved with different levels of leg stiffness. The mechanical power acting on the human body during the positive phase of the drop jumps had the highest values in group 3. This means that there is an optimum stiffness value for the lower extremities to maximize mechanical power.
Journal of Electromyography and Kinesiology 11/2001; 11(5):355-64. DOI:10.1016/S1050-6411(01)00009-8 · 1.65 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The purposes of this study were as follows: (1) To determine the differences between two- and three-dimensionally calculated energy of the athlete in the pole vault. (2) To determine the differences between CM energy and total body energy. (3) To examine the influence of these different approaches of calculating the athlete's energy on energetic parameter values during the pole vault. Kinematic data were gathered during the pole vault final of the track and field world championships in 1997. Two video cameras (50 Hz) covered the last step of the approach including the pole plant and 2 cameras covered the pole phase up to bar clearance, respectively. Twenty successful jumps were analysed. The characteristics of the energy development is similar for the different approaches. Initial energy, energy at maximum pole bend and energy at pole release (primary parameters) show significant differences (p<0.05). The findings indicate that rotatory movements and movements relative to the CM have a larger influence on the primary parameters than movements apart from the main plane of movement. For analysing the energy exchange between the athlete and the elastic implement pole only the differences among the secondary parameters (initial energy minus energy at maximum pole bend, final energy minus energy at maximum pole bend) are needed (Arampatzis et al., 1997 Biomechanical Research Project at the Vth World Championships in Athletics, Athens 1997: Preliminary Report. New Studies in Athletics 13, 66–69). For those parameters the relative differences between the calculation approaches range only between 1.47 and 0.04%. This indicates that the influence of the different approaches for calculating the athlete’s energy on the analysis of energy exchange is negligible.
Journal of Biomechanics 10/2000; 33(10-33):1263-1268. DOI:10.1016/S0021-9290(00)00087-7 · 2.75 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: INTRODUCTION: From the viewpoint of energetics the main difference between the pole vault and the other jumping disciplines is that the transformation of the approach energy to pole release energy or take off energy can take place without an energy loss and sometimes even with an energy gain (Groß and Terauds 1983; Groß and Kunkel 1990, Arampatzis et al. 1997). A large decrease in the athlete's total energy occurs during this transformation in all the other track and field jump disciplines (Brüggemann and Arampatzis 1997; Müller and Brüggemann 1997). The reason for this difference is the elasticity of the poles. Several authors (Dillman and Nelson 1968; Braff and Depena 1985; Ekevad and Lundberg 1997) have attempted to determine the influence of the length and stiffness of the poles on jump performance. The results indicate that an optimum pole stiffness and length can be determined which would allow the pole vaulter to jump to his maximum height (Ekevad and Lundberg 1997). During the pole phase the athlete's muscular energy is used to store energy in the pole (Hubbard 1980; Groß and Terauds 1983; Groß and Kunkel 1990). The resultant shoulder joint moments are much higher than the resultant hip and knee moments (McGinnis and Bergman 1986). Using only the amount of muscular energy production during the pole phase (Groß and Terauds 1983; Groß and Kunkel 1990) it is not possible to identify differentiated deficits in the technical components of the athletes (Arampatzis et al.1997). Arampatzis et al. (1997) outlined 3 criteria which characterize the initial conditions in the pole vault (Criterion 3) as well as the pole vaulter's behavior during the pole phase. During the first part of the pole phase, ending with the maximum pole bend position, energy is transferred into the pole and the total energy of the athlete decreases. The difference between the energy decrease of the athlete and the energy gain of the pole indicates whether this phase of the vault was performed effectively (Criterion 1). During the second part of the pole phase, ending with pole release, energy is transferred back into the athlete and the total energy of the athlete increases. The difference between the returned pole energy and the amount of energy increase of the athlete defines Criterion 2. The main goals of this study were: 1. To examine the behavior and practical application of 3 criteria concerning energy behavior in the pole vault at the world class level. 2. To determine the amount of influence of the initial conditions, as well as the influence of the athlete's behavior during the pole phase on pole vault performance. METHODS: The data for this study was collected at the 1997 World Track and Field Championships in Athens, Greece. 25 successful jumps by 11 pole vaulters during the finals were analyzed 2-dimensionally using two video cameras operating at 50 fields per second. A total of 22 frames from each jump were digitized at specific positions. The video data was digitized using the Peak-Motus system. The