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How to teach safe landing after the jump? The use of biofeedback to minimize the shock forces generated in elements of modern dance

Gorwa Joanna, Michnik Robert, Nowakowska-Lipiec Katarzyna

Acta of Bioengineering and Biomechanics

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2021

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Vol. 23, no. 3

47--59

EN

Purpose: The aim of the study was to assess the possible use of biofeedback (information on the course and values of ground reaction forces (GRF) during landing following the performance of a dance evolution) for training minimising impact loads after a jump in modern dance. Methods: The tests involved the analysis of a total of 60 expressive elements of modern dance performed by 5 soloists. The tests involved the recording of the vertical component of GRF (GRFz) vector using Kistler platform in the landing phase following the performance of modern dance jumps. The dancers performed the above-named jumps three times in successive tests: a reference test (without biofeedback) and the next two tests with biofeedback, after the obtainment of information about the vertical value of GRF. After each performance, the dancers watched a course of GRF and films showing the recorded landing phase. Results: Applying of a proposed didactic laboratory session led to: extension of contact time and of time preceding the obtainment of the maximum value of GRFz, reduction of the maximum values of the vertical components of the GRF, reduction of the loading rate of the ground reaction force, increase of an impulse of the vertical component of GRF in the entire stance phase and in the shock absorption phase. Conclusions: Proposed didactic laboratory session with biofeedback may result in the change of the post-jump shock absorption technique.

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Somatotype variables related to strength and power output in male basketball players

Buśko K., Pastuszak A., Lipińska M., Gryko K.

Acta of Bioengineering and Biomechanics

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2017

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Vol. 19, no. 2

161--167

EN

The purpose of this study was to investigate the relationship between somatotype, muscular strength, power output measured in maximal cycle ergometer exercise bouts, and maximal power output and height of rise of the body mass centre (jump height) measured in akimbo counter movement jump (ACMJ), counter movement jump (CMJ) and spike jump (SPJ), in male basketball players. Methods: Thirteen male basketball players (second division, age 19.4±0.8 years, body height 192.9±5.6 cm, body mass 88.8±8.6 kg, training experience 9.3±0.8 years) participated in the study. Somatotype was determined using the Heath-Carter method. Maximal joint torques were measured under static conditions. Power output was measured in 2 maximal cycle ergometer exercise bouts, 10 s each, with increasing external loads equal to 7.5 and 10.0% of the body weight (BW). All jump trials (ACMJ, CMJ and SPJ) were performed on a force plate. Results: The mean somatotype of basketball players amounted to: 2.8-4.2-3.2. Sum of the joint torques for left and right lower extremities (0.613), trunk (0.631) and all six measured muscle groups (0.647) were significantly correlated (p<0.05) with mesomorphy and ectomorphy. Conclusion: It can be assumed that basketball players’ anthropometric characteristics can influence their level of performance but it is not a decisive factor.

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A simple tridimensional processing of acceleration measurements for dynamic movements monitoring of sportsmen

Neneman K., Łuczyk A. W., Szostak S., Pleskacz W. A.

International Journal of Microelectronics and Computer Science

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2016

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Vol. 7, nr 2

47--53

EN

Measuring, monitoring and analysis of dynamic movements in sports is becoming more important than ever. Many methods used currently may only be applied in the artificial environment of a laboratory. Other methods require too much processing to be used during a real-time competition. To overcome these difficulties acceleration measurements and a simple method to process them have been proposed. Data processing is based on search and recognition of the characteristic points in the tridimensional representation of acceleration measurements. Three different dynamic movements have been measured: run, jump and punch. The presented results show that the measurements of acceleration and proposed processing may be used to extract movement parameters of a sportsman and monitor the level of his tiredness.

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Biomechanics of figure skating jump double axel performed in on ice and off ice conditions

Mazurkiewicz A., Iwańska D.

Aktualne Problemy Biomechaniki

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2015

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z. 9

83--88

EN

Figure skating is considered a highly technical discipline. Coaches and researchers are constantly looking for the most effective and safest movement model for jumps, especially Axel Paulsen, which is the hardest kind of all jumps. This research was taken to verify the usefulness of performing double Axel under off- ice conditions as a part of general figure skating training. Research was based on video analysis made in APAS 2000 programme. Parameters taken into account were: joints and take off angle, displacement of centre body mass, horizontal and vertical velocity. Results helped in finding out parameters which are trained during off-ice session.

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Balance disorders caused by running and jumping occurring in young basketball players

Struzik A., Zawadzki J., Pietraszewski B.

Acta of Bioengineering and Biomechanics

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2015

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Vol. 17, no. 2

103--109

EN

Purpose: Body balance, as one of the coordination abilities,is a desirable variable for basketball players as regards the necessity of efficient responses in constantly changing situations on a basketball court. The aim of this study was to check whether physical activity in the form of running and jumping influences variables characterizing the process of keeping body balance of a basketball player in the standing position. Methods: The research was conducted on 11 young basketball players. The measurements were taken with a Kistler force plate. Apart from commonly registered COP displacements, an additional variable describing the process of keeping body balance by a basketball player was ankle joint stiffness on the basis of which an “Index of Balance–Stiffness” (IB-S) was created. Results: Statistically significant differences were obtained for the maximum COP displacements and ankle joint stiffness between measurements of balance in the standing position before and after the employed movement tasks whereas there were no statistically significant differences for the aforementioned variables describing the process of keeping balance between measurements after running and after jumping. Conclusions: The research results indicate that the employed movement activities brought about significant changes in the process of keeping balance of basketball player in the standing position which, after the run performed, remain on a similar level to the series of jumps being performed. The authors attempted to establish an index based on the stiffness which yields a possibility to perceive each basketball player as an individual person in the process of keeping balance.

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Somatotype : variables related to muscle torque and power output in female volleyball players

Buśko K., Lewandowska J., Lipińska M., Michalski R., Pastuszak A.

Acta of Bioengineering and Biomechanics

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2013

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Vol. 15, no. 2

119--126

EN

The purpose of this study was to investigate the relationship between somatotype, muscle torque, maximal power output and height of rise of the body mass centre measured in akimbo counter movement jump (ACMJ), counter movement jump (CMJ) and spike jump (SPJ), and power output measured in maximal cycle ergometer exercise bouts in female volleyball players. Fourteen players participated in the study. Somatotype was determined using the Heath–Carter method. Maximal muscle torque was measured under static conditions. Power output was measured in 5 maximal cycle ergometer exercise bouts, 10 s each, at increasing external loads equal to 2.5, 5.0, 7.5, 10.0 and 12.5% of body weight (BW). All jump trials (ACMJ, SPJ and CMJ) were performed on a force plate. The mean somatotype of volleyball players was: 4.9-3.5-2.5. The value of the sum of muscle torque of the left upper extremities was significantly correlated only with mesomorphic component. Mesomorphic and ectomorphic components correlated significantly with values of maximal power measured during ACMJ and CMJ. Power output measured in maximal cycle ergometer exercise bouts at increasing external loads equal to 2.5, 5.0 and 7.5% of BW was significantly correlated with endomorphy, mesomorphy and ectomorphy.

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Relative power of the lower limbs in drop jump

Pietraszewski B., Rutkowska-Kucharska A.

Acta of Bioengineering and Biomechanics

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2011

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Vol. 13, no. 1

13-18

EN

The purpose of this paper was to determine the power produced by the lower limbs in the take-off phase in drop jumps (DJ) and the correlation between the power and load measured by dropping height after take-off. The research group (N = 17) contained students practicing football, volleyball, basketball, athletics, high jump, swimming and fencing. The individual characteristics "power-load" of the players and the observation of the changes during the training process enable the coaches to choose precise loads and at the same time to improve the training. The criterion of choosing loads in the plyometric training may be relative power output of lower limbs referred to the DJ height. While the condition allowing player to perform this type of training may depend on obtaining greater power in drop jump than in counter movement jump.

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Effect of increased load on vertical jump mechanical characteristics in acrobats

Król H., Mynarski W.

Acta of Bioengineering and Biomechanics

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2010

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Vol. 12, no. 4

33-37

EN

In this study, we attempt to answer the following question: To what degree the higher muscular activity determined by increased load in the extension phase (eccentric muscle action) of vertical jump affects its efficiency? Ten high performance acrobats participated in this investigation. The acrobats performed tests that consisted of five single “maximal” standing vertical jumps (counter movement jump – CMJ) and five single vertical jumps, in which the task was to touch a bar placed over the jumping acrobats (special counter movement jump – SCMJ). Subsequently, they performed five single drop jumps from an elevation of 0.40 m (DJ). Ground reaction forces were registered using the KISTLER 9182C force platform. MVJ software was used for signal processing [1] and enabling calculations of kinematic and kinetic parameters of the subject’s jumping movements (on-line system). The results obtained show that the height of jump (h), the mean power (Pmean) and the maximum power (Pmax) are statistically significant, and higher in DJ. The results prove fine adaptation of the nervous system in acrobats to muscle extension and workload, due to the 40 cm high drop jump. Presumably, this height is closest to that which acrobats experience during landing, after performing flic-flacs or round-off.