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1

Leg strength and power in Polish striker soccer players

Buśko K., Górski M., Nikolaidis P. T., Mazur-Różycka J., Łach P., Staniak Z., Gajewski J.

Acta of Bioengineering and Biomechanics

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2018

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Vol. 20, no. 2

109--116

EN

The main goal of the present study was to examine muscle strength and power of dominant and non-dominant leg, knee extensors and flexors, and their correlations with jumping performances in soccer players. A secondary aim was to evaluate muscle sense. Methods: 31 male professional strikers (age 20.9 ± 2.3 years, body mass 75.1 ± 6.6 kg, body height 179.5 ± 4.7 cm) participated in the study. The power output of lower extremities and the height of rise of the body mass centre during vertical jumps were measured using a force plate. The maximum muscle torque of the flexors and extensors of the knee were measured under isometric conditions using a special isometric torquemeter. Force sense was measured in isometric conditions in two tests: (a) fifty percent of the maximal voluntary contraction was set as a value of target force and the participants were instructed to reproduce the target force, (b) the participants attempted to develop a torque reproducing a sine course within the range of 10 to 50% of MVC performed. Results: A direct relationship was observed between the peak muscle torque in knee extensors developed during isokinetic contraction at all velocities and power and height of three types of vertical jumps ( p < 0.05). No correlation was observed between jumping performance and muscle torque under isometric condition. No differences were found in strength and jumping abilities as well as in force sense between dominant and non-dominant legs. Conclusions: This study offered a comprehensive and complete evaluation of leg muscle strength, sense and power, with the use of using force plate and isokinetic dynamometry.

2

Countermovement depth – a variable which clarifies the relationship between the maximum power output and height of a vertical jump

Gajewski J., Michalski R., Buśko K., Mazur-Różycka J., Staniak Z.

Acta of Bioengineering and Biomechanics

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2018

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Vol. 20, no. 1

127--134

EN

The aim of this study was to identify the determinants of peak power achieved during vertical jumps in order to clarify relationship between the height of jump and the ability to exert maximum power. Methods: One hundred young (16.8±1.8 years) sportsmen participated in the study (body height 1.861 ± 0.109 m, body weight 80.3 ± 9.2 kg). Each participant performed three jump tests: countermovement jump (CMJ), akimbo countermovement jump (ACMJ), and spike jump (SPJ). A force plate was used to measure ground reaction force and to determine peak power output. The following explanatory variables were included in the model: jump height, body mass, and the lowering of the centre of mass before launch (countermovement depth). A model was created using multiple regression analysis and allometric scaling. Results: The model was used to calculate the expected power value for each participant, which correlated strongly with real values. The value of the coefficient of determination R2 equalled 0.89, 0.90 and 0.98, respectively, for the CMJ, ACMJ, and SPJ jumps. The countermovement depth proved to be a variable strongly affecting the maximum power of jump. If the countermovement depth remains constant, the relative peak power is a simple function of jump height. Conclusions: The results suggest that the jump height of an individual is an exact indicator of their ability to produce maximum power. The presented model has a potential to be utilized under field condition for estimating the maximum power output of vertical jumps.

3

Concurrent validity and reliability of proprietary and open-source jump mat systems for the assessment of vertical jumps in sport sciences

Pueo B., Jimeney-Olmedo J. M., Lipińska P., Buśko K., Penichet-Tomas A.

Acta of Bioengineering and Biomechanics

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2018

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Vol. 20, no. 3

51--57

EN

Vertical jump tests are used to assess lower-limb power of athletes in sport sciences. Flight time measurement with jump-mat systems is the most common procedure for this purpose. The aim of this study was to analyze the concurrent validity and reliability of two proprietary systems (Globus and Axon) and an open-source system (Chronojump). Methods: A conditioning electric circuit governed by a controlled wave generator is designed to substitute athletes jumping on a physical mat. In order to look for possible differences associated to timekeeping by each microcontroller device, all three systems are fed by the circuit simultaneously. Results: Concurrent validity was high for the three systems. Standarized typical error of estimate (TEE) was trivial, according to MBI interpretation, as well as perfect Pearson correlation coefficient. Reliability was assessed using coefficient of variation of flight time measure, resulting in 0.17–0.63% (0.05–0.12 cm) for Globus, 0.01% (0.09 cm) for Chronojump and 5.65–9.38% (2.15–3.53 cm) for Axon. These results show that all jump-mat system produced nearly identical measures of flight time so they can be considered valid and reliable for practical purposes. In comparison, Chronojump showed the best performance whereas Axon showed enough variability and disagreement to pose a problem in testing elite athletes. Conclusions: These experiments show that open-source jump mats are as valid and reliable as their proprietary counterparts at a lower cost. Therefore, practitioners can be confident in using Globus or Chronojump systems to test athletes’ jump height because of their negligible errors and Axon system to monitor general population.

4

Accelerometer profile of motion of the pelvic girdle in butterfly swimming

Staniak Z., Buśko K., Górski M., Pastuszak A.

Acta of Bioengineering and Biomechanics

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2018

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Vol. 20, no. 1

159--167

EN

Purpose: The aim of the study was to develop a method to measure and analyse kinematics of movement of the pelvic girdle in butterfly swimming in order to support training of technical skills. Methods: A device for recording triaxial accelerations and triaxial rotational angular velocities was mounted on the dorsal part of the pelvic girdle of athlete. The measurements were performed in ten elite butterfly swimmers (age: 23.1 ± 3.7 years, body height: 187.6 ± 4.3 cm, body mass 83.4 ± 6.33 kg). The task of the athlete was to swim one length of short course pool at maximal intensity. Individual mean graphical and numerical profiles of the kinematics of the movement of the pelvic girdle was computed, within the average cycle based on five consecutive cycles. Results: Statistical analysis of numerical individual parameters of profiles of the athletes studied revealed statistically significant differences between the swimmers. Statistically significant correlations were also found between personal best times in 50 m swimming (r = –0.76, p < 0.05) and 100 m swimming (r = –0.76, p < 0.05) and duration of the part of the cycle connected with the decline in velocity from maximum translational motion velocity obtained during propulsion with the upper and lower limbs to minimum value of the velocity obtained before the beginning of propulsion only with the lower limbs. Conclusion: The proposed measurement method, presentation and analysis of the profile of the pelvic girdle motion in butterfly swimming represents a good tool for fast and effective qualitative and quantitative biomechanical evaluation of movement technique components.

5

The biomechanical characteristics of elite deaf and hearing female soccer players: comparative analysis

Szulc A. M., Buśko K., Sandurska E., Kołodziejczyk M.

Acta of Bioengineering and Biomechanics

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2017

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Vol. 19, no. 4

127--133

EN

The aim of this study was to examine the differences in body composition, strength and power of lower limbs, height of jump measured for the akimbo counter movement jumps, counter movement jump and spike jumps between deaf and hearing elite female soccer players. Methods: Twenty deaf (age: 23.7 ± 5.0 years, hearing loss: 96 ± 13.9 dB) and 25 hearing (age: 20.3 ± 3.8 years) participated in the study. Their WHR and BMI were calculated. Body fat was measured using the BIA method. The maximal power and height of jump were measured by force plate. Biodex dynamometer was used to evaluate isokinetic isometric strength of the hamstrings and quadriceps. Results: Significant differences between hearing and deaf soccer players in anthropometric values were for the waist and calf circumferences and the WHR index ( p < 0.01, effect size 0.24–0.79). Statistically significant differences were observed for flexion of the lower limb in the knee joint for the relative joint torque and relative power obtained for the angular velocity of 300 degˑs–1 for both lower limbs (p < 0.01, effect size 0.19–0.48) and for 180 degˑs–1 during flexion of the left limb (p = 0.02, effect size 0.13). The hearing female football players developed significantly greater MVC in all the cases. Statistically significant differences between deaf and hearing athletes were found for spike jump for maximal power (1828.6 ± 509.4 W and 2215.2 ± 464.5 W, respectively; p = 0.02, effect size 0.14). Conclusions: Hearing impairment does not limit the opportunities for development of physical fitness in the population of deaf women.

6

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.

7

Measuring the force of punches and kicks among combat sport athletes using a modified punching bag with an embedded accelerometer

Buśko K., Staniak Z., Szark-Eckardt M., Nikolaidis P. T., Mazur-Różycka J., Łach P., Michalski R., Gajewski J., Górski M.

Acta of Bioengineering and Biomechanics

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2016

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Vol. 18, no. 1

47--54

EN

The main aim of the study was to design a new system to measure punching and kicking forces as well as reaction times in combat sport athletes. In addition, the study examined whether there were any intergender differences in the force of punches thrown by boxers and kicking forces delivered by taekwondo athletes. Boxers (male, n = 13; female, n = 7) were examined for the force of single straight punches and taekwondo athletes (male, n = 14; female, n = 14) for force of single Apdolio and Dwit Chagi kicks. The punching bag was equipped with acceleration transducers and gyroscopes embedded in a cylinder covered with a layer to absorb shock as well as a set of colour signal diodes. Value of the punching bag’s acceleration was used for calculating: strike force; the punching location on the bag; and time of a strike. The relative error of force calculation was 3%; the relative error in acceleration measurement was less than 1%. The force of a straight rear-hand punch was greater than the force of a lead-hand punch among male and female boxers. The force of Apdolio kick delivered with a rear leg was greater compared to a lead leg among female and male taekwondo athletes. Significant gender differences were noticed in the force in both types of kicks. In boxers, intergender differences were reported only for the force of a punch thrown with the rear hand. Based on these findings, it was concluded that the modified punching bag is a good diagnostic tool for combat sports.

8

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.

9

Changes of the maximal muscle torque of male volleyball players during training

Buśko K., Staniak Z.

Zeszyty Naukowe Katedry Mechaniki Stosowanej / Politechnika Śląska

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2006

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z. 26

47-50

EN

The aim of the study was to follow the changes of the maximal muscle torque of male volleyball players during training performed in the preparatory and starting period. Muscle torque measurements in static conditions were performed in preparatory (I, III) and starting (II, IV) periods for two years. The sum of muscle torque of the trunk and sum of muscle torque of lower extremities were decreases between I and II period, and increases between III and IV period. The sum of muscle torque of upper extremities were significantly increases between III and IV period. The significant differences between II and IV period were observed for upper extremities.

10

Analyze of vertical acceleration of the body mass center during running on treadmill

Staniak Z., Buśko K., Karpiłowski B., Nosarzewski Z., Witek K.

Zeszyty Naukowe Katedry Mechaniki Stosowanej / Politechnika Śląska

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2006

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z. 26

339-344

EN

The work presents analyze of vertical acceleration curve of the body mass center (VACM characteristic) obtained by eleven athletes during on treadmill running with gradual rise velocity. The measurements are made by uniaxial accelerometer placed in loins part of trunk near the center of body mass. The chosen value of characteristics was calculated for every single run with applied velocity of treadmill The velocity of treadmill of every run was significantly correlated to mean values of VACM characteristics calculated for all subjects. For every athletes analyzed mean values of characteristics calculated separately for left and right steps were significantly different.

11

Changes in power output under the influence of sprint training in handball players

Norkowski H., Buśko K.

Acta of Bioengineering and Biomechanics

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2004

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Vol. 6, nr 1

31-40

EN

The purpose of this paper was to study the power output using the Wingate test applied in an eight-week training programme realized by handball players, aided by repeated maximal-intensity exercise on a cycle ergometer. The study was conducted on 13 handball players divided into two groups. Group GS (n = 5) done the training in a gym and an additional sprint training on a cycle ergometer, wile group GG (n = 8) performed only the training in a gym. Both training programmes lasted 8 weeks, 5 times a week (Monday to Friday). On Saturday preceding the stan of the experiment and Saturday at the end of each week during the 8-week training programmes, the participants of the experiment came through the Wingate test on a cycle ergometer. The sprint training on the cycle ergometer caused a significant improvement in alactic anaerobic output (the power increase and maintenance phase - IMP) in the Wingate test (8.3% PalMp) and in lactic anaerobic out-put (the power decrease phase - DP) (13.3% PaDP) in group GS. No significant changes in these values were faund in these participants of the Wingate test who belonged to the group GG. The changes in the parameters measured in both groups examined varied significantly.

12

Changes in power output under the influence of high-intensity training

Norkowski H., Sozański H., Buśko K.

Acta of Bioengineering and Biomechanics

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2003

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Vol. 5, nr 2

89-99

EN

The purpose of this research was to study the effect of high-intensity training programme carried out with a cycle ergometer and in the form of run intervals on physical fitness as measured in a running test and on power output measured in Wingate test. The study was carried out on 24 subjects divided into two groups: group GC (12 persons) did the high-intensity training on a cycle ergometer; group GR (12 persons) did the training in the form of running. The training lasted 8 weeks, 5 times a week in both groups. Running test consisted of a series of four 50 m sprints (25 m + 25 m back) at 15-second intervals. The training improved alactic anaerobic output (the phase of power increase and maintenance phase (IMP) in the Wingate test) by 20.3%- VV[IMP] and 9.1%P[AlMP] in the GC group and by 15.2% W[IMP] and 11.5% P[aIMP] in the GR group, and lactic anaerobic output (the phase of power decrease (DP)) by 9.1% W[DP] and 12.4% P[aDP] for group GC and by 12.8% W[DP] and 10.8% P[[aDP] for group GR. In both groups, a significant improvement in time required to cover the distance in the series of four runs was noted (significantly larger in the group GR than in the group GC). The changes in running times, in terms of percentages, differed significantly between the groups. However, the groups did not differ in terms of their Wingate test results.