The aim of the present study was to evaluate the level of agreement between the routinely used &q... more The aim of the present study was to evaluate the level of agreement between the routinely used "multiple-load method" and a simple "two-load method" based on direct assessment of the F-V relationship from only 2 external loads applied. Twelve participants were tested on the maximum performance vertical jumps, cycling, bench press throws, and bench pull performed against a variety of different loads. All four tested tasks revealed both exceptionally strong relationships between the parameters of the 2 methods (median R = 0.98) and a lack of meaningful differences between their magnitudes (fixed bias below 3.4%). Therefore, addition of another load to the standard tests of various functional tasks typically conducted under a single set of mechanical conditions could allow for the assessment of the muscle mechanical properties, such as the muscle F, V, and P producing capacities.
The recently proposed two-point force-velocity (F-V) model requires further evaluation in order t... more The recently proposed two-point force-velocity (F-V) model requires further evaluation in order to develop into a simple tool for muscle mechanical capacities assessment. Therefore, the first aim of this study was to assess the concurrent validity of the proposed model. The second aim of this study was to assess the sensitivity of the proposed model concerning participants of different levels of physical fitness when performing different dynamic tasks. Female elite volleyball players (N = 10; age 22 ± 2 years) and female physical education students (N = 10; age 22 ± 2 years) were tested on maximum countermovement jumps (CMJ) and 6 s maximal cycling sprint (MCS), where manipulation of loads provided a range of F and V data. The assessed F-V relationships were valid in comparison with the standard model. Moreover, the concurrent validity of the maximum force parameter (F 0) was high for MCS (r ≥ 0.89) and moderate to low for CMJ (r = 0.43). Sensitivity analysis revealed significant differences between F 0 in both leg tests (p < 0.04), along with maximum power parameter in CMJ (p = 0.034) between the groups. The proposed model could provide sport practitioners with a straightforward and very effective tool for assessing muscle mechanical capacities.
The assessment of muscle mechanical properties in multi-joint movements reveals inverse correlati... more The assessment of muscle mechanical properties in multi-joint movements reveals inverse correlation of leg muscle force and power with gait transition speed
The force‐velocity (F‐V) relationship observed in multi‐joint tasks proved to be strong and appro... more The force‐velocity (F‐V) relationship observed in multi‐joint tasks proved to be strong and approximately linear. Recent studies showed that mechanical properties of muscles: force (F), velocity (V) and power (P) could be assessed through the F‐V relationship although the testing methods have not been standardized. The aim of the present study was to evaluate and compare F‐V relationships assessed from two tests performed on a modified Smith machine that standardizes kinematics of the movement pattern. Fifteen participants were tested on the maximum performance bench press throws and squat jumps performed against a variety of different loads. In addition, their strength properties were assessed through maximum isometric force (Fiso) and one repetition maximum (1 RM). The observed individual F‐V relationships were exceptionally strong and approximately linear (r = 0.98 for bench press throws; r = 0.99 for squat jumps). F‐V relationship parameter depicting maximum force (F0) revealed ...
The aim of this study was to compare the reliability and magnitude of the force-velocity (F-V) re... more The aim of this study was to compare the reliability and magnitude of the force-velocity (F-V) relationship parameters [maximum force (F0), maximum velocity (V0), F-V slope, and maximum power (P0)] obtained through the application of only two loads (i.e., two-point method) vs. six loads (i.e., multiple-point method). Methods Ten physically active men (age 19.5 ± 0.9 years, body mass 79.0 ± 9.0 kg, height 183.9 ± 8.4 cm) conducted four testing sessions after a preliminary familiarization session with the leg cycle ergometer exercise. In a counterbalanced order, subjects performed two sessions of the multiple-point method (six loads applied for the F-V modeling) over 1 week and two sessions of the two-point method (only the lightest and heaviest loads were applied) over another week. Results The main findings revealed that (I) the reliability of the F-V relationship parameters was very high and generally of comparable magnitude for both the multiple-[coefficient of variation (CV) range 1.91-3.94%; intraclass correlation coefficient (ICC) range 0.72-0.99] and two-point methods [CV range 1.41-4.62%; ICC range 0.76-0.95], (II) the magnitude of the same parameters obtained from both methods was highly correlated (r > 0.80), and (III) the P0 assessed from the multiplepoint method was significantly lower than the obtained from the two-point method [P = 0.041; effect size (ES) 0.36] due to a significant decrease in F0 (P = 0.039; ES 0.41) with no significant differences observed for V0 (P = 0.570; ES − 0.15). Conclusions These results support the two-point method as a reliable, valid, and fatigue-free procedure of assessing the muscle mechanical capacities through the F-V relationship. Keywords Force-velocity relationship • Maximum force • Maximum velocity • Maximum power Abbreviations A Linear regression slope CV Coefficient of variation ES Cohen's d effect size F 0 Regression parameter (F-intercept) depicting maximum force F-V Force-velocity ICC Intraclass correlation coefficient L1 Load 1 L2 Load 2 L3 Load 3 L4 Load 4 L5 Load 5 L6 Load 6 P 0 Regression parameter [(F 0 × V 0)/4] depicting maximum power r Pearson's correlation coefficient Communicated by Toshio Moritani.
Journal of Strength and Conditioning Research, 2019
Effect of different types of loads on the force-velocity relationship obtained during the bench p... more Effect of different types of loads on the force-velocity relationship obtained during the bench press throw exercise. J Strength Cond Res XX(X): 000-000, 2019-This study aimed (a) to evaluate the degree of linearity of the force-velocity (F-V) relationship across different types of loads, (b) to compare the magnitude of the F-V relationship parameters (maximum values of force [F 0 ], velocity [V 0 ], and power [Pmax]) between the different types of loads, and (c) to explore the concurrent validity of F 0 with traditional measures of maximal strength. The F-V relationships of 15 physically active men (age: 20.9 6 2.0 years, bench press 1 repetition maximum relative to body mass: 1.20 6 0.10 kg•kg 21) were determined during the bench press throw exercise using predominantly gravitational (W), inertial (I), and combined (W + I) loads. The bench press maximal isometric force (F iso) and the 1RM were also assessed. The individual F-V relationships were highly linear regardless of the type of load considered (median r [range] 5 0.98 [0.94, 1.00]). The W + I load provided the largest value of F 0 (972 6 45 N; 6.0 and 14.6% higher than W and I, respectively), the I load the largest value of V 0 (2.99 6 0.34 m•s 21 ; 40.4 and 20.1% higher than W and W + I, respectively), and the W load the lowest value of Pmax (501 6 46 W; 222.7 and 217.1% lower than I and W + I, respectively). The F 0 obtained from the W load presented the highest association with F iso and 1RM values (r. 0.90). The W + I load and the I load should be recommended to work closer to the F 0 and V 0 capacities, respectively. However, the W load should be recommended to assess maximal strength capacity through the value of F 0 .
Single outcomes of standard isokinetic dynamometry tests do not discern between various muscle me... more Single outcomes of standard isokinetic dynamometry tests do not discern between various muscle mechanical capacities. In this study, we aimed to (1) evaluate the shape and strength of the force-velocity relationship of knee extensors, as observed in isokinetic tests conducted at a wide range of angular velocities, and (2) explore the concurrent validity of a simple 2-velocity method. Thirteen physically active females were tested for both the peak and averaged knee extensor concentric force exerted at the angular velocities of 30°–240°/s recorded in the 90°–170° range of knee extension. The results revealed strong (0.960
Highlights • Subjects exerted maximum horizontal force while walking on a motorized treadmill • T... more Highlights • Subjects exerted maximum horizontal force while walking on a motorized treadmill • The resulting force-velocity relationship was linear, strong, and reliable • The relationship parameters reveal muscle force, velocity, and strength capacities • Almost identical outcomes were observed from only two velocities tested • The 'two-velocity method' could be developed in a routine test of leg muscles
The aims of the present study were to investigate the shape and strength of the force-velocity re... more The aims of the present study were to investigate the shape and strength of the force-velocity relationships observed in different functional movement tests and explore the parameters depicting force, velocity and power producing capacities of the tested muscles. Twelve subjects were tested on maximum performance in vertical jumps, cycling, bench press throws, and bench pulls performed against different loads. Thereafter, both the averaged and maximum force and velocity variables recorded from individual trials were used for force–velocity relationship modeling. The observed individual force-velocity relationships were exceptionally strong (median correlation coefficients ranged from r = 0.930 to r = 0.995) and approximately linear independently of the test and variable type. Most of the relationship parameters observed from the averaged and maximum force and velocity variable types were strongly related in all tests (r = 0.789-0.991), except for those in vertical jumps (r = 0.485-0...
A range of force (F) and velocity (V) data obtained from functional movement tasks (e.g., running... more A range of force (F) and velocity (V) data obtained from functional movement tasks (e.g., running, jumping, throwing, lifting, cycling) performed under variety of external loads have typically revealed strong and approximately linear F-V relationships. The regression model parameters reveal the maximum F (F-intercept), V (V-intercept), and power (P) producing capacities of the tested muscles. The aim of the present study was to evaluate the level of agreement between the routinely used &amp;amp;amp;amp;amp;amp;quot;multiple-load model&amp;amp;amp;amp;amp;amp;quot; and a simple &amp;amp;amp;amp;amp;amp;quot;two-load model&amp;amp;amp;amp;amp;amp;quot; based on direct assessment of the F-V relationship from only 2 external loads applied. Twelve participants were tested on the maximum performance vertical jumps, cycling, bench press throws, and bench pull performed against a variety of different loads. All 4 tested tasks revealed both exceptionally strong relationships between the parameters of the 2 models (median R = 0.98) and a lack of meaningful differences between their magnitudes (fixed bias below 3.4%). Therefore, addition of another load to the standard tests of various functional tasks typically conducted under a single set of mechanical conditions could allow for the assessment of the muscle mechanical properties such as the muscle F, V, and P producing capacities.
International Journal of Sports Physiology and Performance, 2016
Purpose:To explore the effects of training against mechanically different types of loads on muscl... more Purpose:To explore the effects of training against mechanically different types of loads on muscle force (F), velocity (V), and power (P) outputs.Methods:Subjects practiced maximum bench throws over 8 wk against a bar predominantly loaded by approximately constant external force (weight), weight plates (weight plus inertia), or weight plates whose weight was compensated by a constant external force pulling upward (inertia). Instead of a typically applied single trial performed against a selected load, the pretest and posttest consisted of the same task performed against 8 different loads ranging from 30% to 79% of the subject’s maximum strength applied by adding weight plates to the bar. That provided a range of F and V data for subsequent modeling by linear F–V regression revealing the maximum F (F-intercept), V (V-intercept), and P (P = FV/4).Results:Although all 3 training conditions resulted in increased P, the inertia type of the training load could be somewhat more effective t...
Према извештају Светске здравствене организације, недовољна физичка активност, тј. хипокинезија, ... more Према извештају Светске здравствене организације, недовољна физичка активност, тј. хипокинезија, проглашена је за самостални ризико фактор (Митић, 2001). Читава биолошка форма и структура људског организма је предодређена кретању (Бошковић, 2005). Нема ни једне једине ћелије у организму, укључујући и најселективније органе и системе, којима улога у функцији одржавања кретања није један од најбитнијих задатака, а који макар и само малим делом не утичу на остваривање покрета (Угарковић, 2004). Током дугог периода психофизичког развоја људског организма, због нових функционалних захтева, органи константно мењају изглед и структуру, а једна од очигледнијих промена везана је за постурални статус (Косинац, 2008), поготово уочљива код деце у школском узрасту. Резултати систематских прегледа и многобројних истраживања говоре у прилог томе. Саша Ђурић Даница Јанићијевић Никола Мајсторовић 796.325-055.2:615.83 Дејан Илић Оригинални научни чланак Универзитет у Београду, Факултет спорта и физичког васпитања ПОСТУРАЛНИ СТАТУС ОДБОЈКАШИЦА УЗРАСТА ОД 12 ДО 16 ГОДИНА Сажетак У периоду развоја деце долази до морфолошких, моторичких, физиолошких и психолошких трансформација, које могу на привремен или трајан начин мењати телесно држање и природне облике људског организма. Многа истраживања, као и систематски прегледи показују да је све већи број школске деце са нарушеним телесним статусом. Истраживања говоре у прилог томе да многе спортске гране у којима су заступљени велики обртни моменти и асиметрично ангажовање мускулатуре, представљају предуслов за појаву асиметрије кичменог стуба. Такође, неким истраживањима показано је да су девојчице подложније девијацијама кичменог стуба од дечака. Циљ истраживања био је детекција постуралног статуса одбојкашица О.К. "Eaton Srem Tempo" из Сремске Митровице. Узорак испитаника је обухватио 72 одбојкашице узраста од 12 до 16 година. Методе које су коришћене за детекцију евентуалних постуралних поремећаја су клиничка метода и метода плантографије чији су резултати тумачени Томсеновом методом. Према добијеним резултатима истраживања, дошло се до закључка да неправилан постурални статус има 68% одбојкашица (клиничка метода), док неправилан статус стопала има 58% одбојкашица (метода плантографије). Најзаступљеније телесне неправилности које су уочене су: хиперекстензија зглоба колена (код 34.72%), затим неједнаки Лоренцови троуглови, односно троуглови стаса (код 26.39%) и неправилан положај рамена (код 25% испитаница). Урађена је и корелациона анализа између вредности индекса телесне масе и индекса спуштености левог и десног стопала. Добијене вредности коефицијената корелације су 0.055 за лево и 0.083 за десно стопало. Због природе добијених резултата, од изузетног је значаја спровођење превентивно-корективних мера. За то се веома ефикасно могу користити одређене спортске игре, а постоје расправе различитих аутора да ли то може бити и одбојка. Њихову примену потребно је прилагодити полу, узрасту, телесном статусу, тренутном физичком и функционалном стању појединца, односно циљу који се жели постићи.
A number of recent studies have revealed an approximately linear force-velocity (F-V) and, conseq... more A number of recent studies have revealed an approximately linear force-velocity (F-V) and, consequently, a parabolic power-velocity (P-V) relationship of multi-joint tasks. However, the measurement characteristics of their parameters have been neglected, particularly those regarding arm muscles, which could be a problem for using the linear F-V model in both research and routine testing. Therefore, the aims of the present study were to evaluate the strength, shape, reliability, and concurrent validity of the F-V relationship of arm muscles. Twelve healthy participants performed maximum bench press throws against loads ranging from 20 to 70 % of their maximum strength, and linear regression model was applied on the obtained range of F and V data. One-repetition maximum bench press and medicine ball throw tests were also conducted. The observed individual F-V relationships were exceptionally strong (r = 0.96-0.99; all P < 0.05) and fairly linear, although it remains unresolved whet...
The aim of the present study was to evaluate the level of agreement between the routinely used &q... more The aim of the present study was to evaluate the level of agreement between the routinely used "multiple-load method" and a simple "two-load method" based on direct assessment of the F-V relationship from only 2 external loads applied. Twelve participants were tested on the maximum performance vertical jumps, cycling, bench press throws, and bench pull performed against a variety of different loads. All four tested tasks revealed both exceptionally strong relationships between the parameters of the 2 methods (median R = 0.98) and a lack of meaningful differences between their magnitudes (fixed bias below 3.4%). Therefore, addition of another load to the standard tests of various functional tasks typically conducted under a single set of mechanical conditions could allow for the assessment of the muscle mechanical properties, such as the muscle F, V, and P producing capacities.
The recently proposed two-point force-velocity (F-V) model requires further evaluation in order t... more The recently proposed two-point force-velocity (F-V) model requires further evaluation in order to develop into a simple tool for muscle mechanical capacities assessment. Therefore, the first aim of this study was to assess the concurrent validity of the proposed model. The second aim of this study was to assess the sensitivity of the proposed model concerning participants of different levels of physical fitness when performing different dynamic tasks. Female elite volleyball players (N = 10; age 22 ± 2 years) and female physical education students (N = 10; age 22 ± 2 years) were tested on maximum countermovement jumps (CMJ) and 6 s maximal cycling sprint (MCS), where manipulation of loads provided a range of F and V data. The assessed F-V relationships were valid in comparison with the standard model. Moreover, the concurrent validity of the maximum force parameter (F 0) was high for MCS (r ≥ 0.89) and moderate to low for CMJ (r = 0.43). Sensitivity analysis revealed significant differences between F 0 in both leg tests (p < 0.04), along with maximum power parameter in CMJ (p = 0.034) between the groups. The proposed model could provide sport practitioners with a straightforward and very effective tool for assessing muscle mechanical capacities.
The assessment of muscle mechanical properties in multi-joint movements reveals inverse correlati... more The assessment of muscle mechanical properties in multi-joint movements reveals inverse correlation of leg muscle force and power with gait transition speed
The force‐velocity (F‐V) relationship observed in multi‐joint tasks proved to be strong and appro... more The force‐velocity (F‐V) relationship observed in multi‐joint tasks proved to be strong and approximately linear. Recent studies showed that mechanical properties of muscles: force (F), velocity (V) and power (P) could be assessed through the F‐V relationship although the testing methods have not been standardized. The aim of the present study was to evaluate and compare F‐V relationships assessed from two tests performed on a modified Smith machine that standardizes kinematics of the movement pattern. Fifteen participants were tested on the maximum performance bench press throws and squat jumps performed against a variety of different loads. In addition, their strength properties were assessed through maximum isometric force (Fiso) and one repetition maximum (1 RM). The observed individual F‐V relationships were exceptionally strong and approximately linear (r = 0.98 for bench press throws; r = 0.99 for squat jumps). F‐V relationship parameter depicting maximum force (F0) revealed ...
The aim of this study was to compare the reliability and magnitude of the force-velocity (F-V) re... more The aim of this study was to compare the reliability and magnitude of the force-velocity (F-V) relationship parameters [maximum force (F0), maximum velocity (V0), F-V slope, and maximum power (P0)] obtained through the application of only two loads (i.e., two-point method) vs. six loads (i.e., multiple-point method). Methods Ten physically active men (age 19.5 ± 0.9 years, body mass 79.0 ± 9.0 kg, height 183.9 ± 8.4 cm) conducted four testing sessions after a preliminary familiarization session with the leg cycle ergometer exercise. In a counterbalanced order, subjects performed two sessions of the multiple-point method (six loads applied for the F-V modeling) over 1 week and two sessions of the two-point method (only the lightest and heaviest loads were applied) over another week. Results The main findings revealed that (I) the reliability of the F-V relationship parameters was very high and generally of comparable magnitude for both the multiple-[coefficient of variation (CV) range 1.91-3.94%; intraclass correlation coefficient (ICC) range 0.72-0.99] and two-point methods [CV range 1.41-4.62%; ICC range 0.76-0.95], (II) the magnitude of the same parameters obtained from both methods was highly correlated (r > 0.80), and (III) the P0 assessed from the multiplepoint method was significantly lower than the obtained from the two-point method [P = 0.041; effect size (ES) 0.36] due to a significant decrease in F0 (P = 0.039; ES 0.41) with no significant differences observed for V0 (P = 0.570; ES − 0.15). Conclusions These results support the two-point method as a reliable, valid, and fatigue-free procedure of assessing the muscle mechanical capacities through the F-V relationship. Keywords Force-velocity relationship • Maximum force • Maximum velocity • Maximum power Abbreviations A Linear regression slope CV Coefficient of variation ES Cohen's d effect size F 0 Regression parameter (F-intercept) depicting maximum force F-V Force-velocity ICC Intraclass correlation coefficient L1 Load 1 L2 Load 2 L3 Load 3 L4 Load 4 L5 Load 5 L6 Load 6 P 0 Regression parameter [(F 0 × V 0)/4] depicting maximum power r Pearson's correlation coefficient Communicated by Toshio Moritani.
Journal of Strength and Conditioning Research, 2019
Effect of different types of loads on the force-velocity relationship obtained during the bench p... more Effect of different types of loads on the force-velocity relationship obtained during the bench press throw exercise. J Strength Cond Res XX(X): 000-000, 2019-This study aimed (a) to evaluate the degree of linearity of the force-velocity (F-V) relationship across different types of loads, (b) to compare the magnitude of the F-V relationship parameters (maximum values of force [F 0 ], velocity [V 0 ], and power [Pmax]) between the different types of loads, and (c) to explore the concurrent validity of F 0 with traditional measures of maximal strength. The F-V relationships of 15 physically active men (age: 20.9 6 2.0 years, bench press 1 repetition maximum relative to body mass: 1.20 6 0.10 kg•kg 21) were determined during the bench press throw exercise using predominantly gravitational (W), inertial (I), and combined (W + I) loads. The bench press maximal isometric force (F iso) and the 1RM were also assessed. The individual F-V relationships were highly linear regardless of the type of load considered (median r [range] 5 0.98 [0.94, 1.00]). The W + I load provided the largest value of F 0 (972 6 45 N; 6.0 and 14.6% higher than W and I, respectively), the I load the largest value of V 0 (2.99 6 0.34 m•s 21 ; 40.4 and 20.1% higher than W and W + I, respectively), and the W load the lowest value of Pmax (501 6 46 W; 222.7 and 217.1% lower than I and W + I, respectively). The F 0 obtained from the W load presented the highest association with F iso and 1RM values (r. 0.90). The W + I load and the I load should be recommended to work closer to the F 0 and V 0 capacities, respectively. However, the W load should be recommended to assess maximal strength capacity through the value of F 0 .
Single outcomes of standard isokinetic dynamometry tests do not discern between various muscle me... more Single outcomes of standard isokinetic dynamometry tests do not discern between various muscle mechanical capacities. In this study, we aimed to (1) evaluate the shape and strength of the force-velocity relationship of knee extensors, as observed in isokinetic tests conducted at a wide range of angular velocities, and (2) explore the concurrent validity of a simple 2-velocity method. Thirteen physically active females were tested for both the peak and averaged knee extensor concentric force exerted at the angular velocities of 30°–240°/s recorded in the 90°–170° range of knee extension. The results revealed strong (0.960
Highlights • Subjects exerted maximum horizontal force while walking on a motorized treadmill • T... more Highlights • Subjects exerted maximum horizontal force while walking on a motorized treadmill • The resulting force-velocity relationship was linear, strong, and reliable • The relationship parameters reveal muscle force, velocity, and strength capacities • Almost identical outcomes were observed from only two velocities tested • The 'two-velocity method' could be developed in a routine test of leg muscles
The aims of the present study were to investigate the shape and strength of the force-velocity re... more The aims of the present study were to investigate the shape and strength of the force-velocity relationships observed in different functional movement tests and explore the parameters depicting force, velocity and power producing capacities of the tested muscles. Twelve subjects were tested on maximum performance in vertical jumps, cycling, bench press throws, and bench pulls performed against different loads. Thereafter, both the averaged and maximum force and velocity variables recorded from individual trials were used for force–velocity relationship modeling. The observed individual force-velocity relationships were exceptionally strong (median correlation coefficients ranged from r = 0.930 to r = 0.995) and approximately linear independently of the test and variable type. Most of the relationship parameters observed from the averaged and maximum force and velocity variable types were strongly related in all tests (r = 0.789-0.991), except for those in vertical jumps (r = 0.485-0...
A range of force (F) and velocity (V) data obtained from functional movement tasks (e.g., running... more A range of force (F) and velocity (V) data obtained from functional movement tasks (e.g., running, jumping, throwing, lifting, cycling) performed under variety of external loads have typically revealed strong and approximately linear F-V relationships. The regression model parameters reveal the maximum F (F-intercept), V (V-intercept), and power (P) producing capacities of the tested muscles. The aim of the present study was to evaluate the level of agreement between the routinely used &amp;amp;amp;amp;amp;amp;quot;multiple-load model&amp;amp;amp;amp;amp;amp;quot; and a simple &amp;amp;amp;amp;amp;amp;quot;two-load model&amp;amp;amp;amp;amp;amp;quot; based on direct assessment of the F-V relationship from only 2 external loads applied. Twelve participants were tested on the maximum performance vertical jumps, cycling, bench press throws, and bench pull performed against a variety of different loads. All 4 tested tasks revealed both exceptionally strong relationships between the parameters of the 2 models (median R = 0.98) and a lack of meaningful differences between their magnitudes (fixed bias below 3.4%). Therefore, addition of another load to the standard tests of various functional tasks typically conducted under a single set of mechanical conditions could allow for the assessment of the muscle mechanical properties such as the muscle F, V, and P producing capacities.
International Journal of Sports Physiology and Performance, 2016
Purpose:To explore the effects of training against mechanically different types of loads on muscl... more Purpose:To explore the effects of training against mechanically different types of loads on muscle force (F), velocity (V), and power (P) outputs.Methods:Subjects practiced maximum bench throws over 8 wk against a bar predominantly loaded by approximately constant external force (weight), weight plates (weight plus inertia), or weight plates whose weight was compensated by a constant external force pulling upward (inertia). Instead of a typically applied single trial performed against a selected load, the pretest and posttest consisted of the same task performed against 8 different loads ranging from 30% to 79% of the subject’s maximum strength applied by adding weight plates to the bar. That provided a range of F and V data for subsequent modeling by linear F–V regression revealing the maximum F (F-intercept), V (V-intercept), and P (P = FV/4).Results:Although all 3 training conditions resulted in increased P, the inertia type of the training load could be somewhat more effective t...
Према извештају Светске здравствене организације, недовољна физичка активност, тј. хипокинезија, ... more Према извештају Светске здравствене организације, недовољна физичка активност, тј. хипокинезија, проглашена је за самостални ризико фактор (Митић, 2001). Читава биолошка форма и структура људског организма је предодређена кретању (Бошковић, 2005). Нема ни једне једине ћелије у организму, укључујући и најселективније органе и системе, којима улога у функцији одржавања кретања није један од најбитнијих задатака, а који макар и само малим делом не утичу на остваривање покрета (Угарковић, 2004). Током дугог периода психофизичког развоја људског организма, због нових функционалних захтева, органи константно мењају изглед и структуру, а једна од очигледнијих промена везана је за постурални статус (Косинац, 2008), поготово уочљива код деце у школском узрасту. Резултати систематских прегледа и многобројних истраживања говоре у прилог томе. Саша Ђурић Даница Јанићијевић Никола Мајсторовић 796.325-055.2:615.83 Дејан Илић Оригинални научни чланак Универзитет у Београду, Факултет спорта и физичког васпитања ПОСТУРАЛНИ СТАТУС ОДБОЈКАШИЦА УЗРАСТА ОД 12 ДО 16 ГОДИНА Сажетак У периоду развоја деце долази до морфолошких, моторичких, физиолошких и психолошких трансформација, које могу на привремен или трајан начин мењати телесно држање и природне облике људског организма. Многа истраживања, као и систематски прегледи показују да је све већи број школске деце са нарушеним телесним статусом. Истраживања говоре у прилог томе да многе спортске гране у којима су заступљени велики обртни моменти и асиметрично ангажовање мускулатуре, представљају предуслов за појаву асиметрије кичменог стуба. Такође, неким истраживањима показано је да су девојчице подложније девијацијама кичменог стуба од дечака. Циљ истраживања био је детекција постуралног статуса одбојкашица О.К. "Eaton Srem Tempo" из Сремске Митровице. Узорак испитаника је обухватио 72 одбојкашице узраста од 12 до 16 година. Методе које су коришћене за детекцију евентуалних постуралних поремећаја су клиничка метода и метода плантографије чији су резултати тумачени Томсеновом методом. Према добијеним резултатима истраживања, дошло се до закључка да неправилан постурални статус има 68% одбојкашица (клиничка метода), док неправилан статус стопала има 58% одбојкашица (метода плантографије). Најзаступљеније телесне неправилности које су уочене су: хиперекстензија зглоба колена (код 34.72%), затим неједнаки Лоренцови троуглови, односно троуглови стаса (код 26.39%) и неправилан положај рамена (код 25% испитаница). Урађена је и корелациона анализа између вредности индекса телесне масе и индекса спуштености левог и десног стопала. Добијене вредности коефицијената корелације су 0.055 за лево и 0.083 за десно стопало. Због природе добијених резултата, од изузетног је значаја спровођење превентивно-корективних мера. За то се веома ефикасно могу користити одређене спортске игре, а постоје расправе различитих аутора да ли то може бити и одбојка. Њихову примену потребно је прилагодити полу, узрасту, телесном статусу, тренутном физичком и функционалном стању појединца, односно циљу који се жели постићи.
A number of recent studies have revealed an approximately linear force-velocity (F-V) and, conseq... more A number of recent studies have revealed an approximately linear force-velocity (F-V) and, consequently, a parabolic power-velocity (P-V) relationship of multi-joint tasks. However, the measurement characteristics of their parameters have been neglected, particularly those regarding arm muscles, which could be a problem for using the linear F-V model in both research and routine testing. Therefore, the aims of the present study were to evaluate the strength, shape, reliability, and concurrent validity of the F-V relationship of arm muscles. Twelve healthy participants performed maximum bench press throws against loads ranging from 20 to 70 % of their maximum strength, and linear regression model was applied on the obtained range of F and V data. One-repetition maximum bench press and medicine ball throw tests were also conducted. The observed individual F-V relationships were exceptionally strong (r = 0.96-0.99; all P < 0.05) and fairly linear, although it remains unresolved whet...
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