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Slobodan Jaric - One of the best experts on this subject based on the ideXlab platform.
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is test standardization important when arm and leg muscle mechanical properties are assessed through the Force Velocity Relationship
Journal of Human Kinetics, 2019Co-Authors: Marko Cosic, Slobodan Jaric, Aleksandar Nedeljkovic, Sasa Djuric, Milena Z Zivkovic, Bojan LeontijevicAbstract: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 high correlations with both Fiso and 1 RM indicating high concurrent validity (p < 0.01). However, the generalizability of F-V Relationship parameters depicting maximum Force (F0), Velocity (V0) and power (P0) of the tested muscle groups was inconsistent and on average low (i.e. F0; r = -0.24) to moderate (i.e. V0 and P0; r = 0.54 and r = 0.64, respectively; both p < 0.05). We concluded that the F-V Relationship could be used for the assessment of arm and leg muscle mechanical properties when standard tests are applied, since the typical outcome is an exceptionally strong and linear F-V Relationship, as well as high concurrent validity of its parameters. However, muscle mechanical properties could be only partially generalized across different tests and muscles.
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comparison of different regression models to fit the Force Velocity Relationship of a knee extension exercise
Sports Biomechanics, 2018Co-Authors: Eliseo Iglesiassoler, Juan Farinas, Xian Mayo, Luis Santos, Slobodan JaricAbstract:The aims of this study were to compare the goodness of fit and the concurrent validity of three regression models of the Force-Velocity Relationship in a unilateral knee extension exercise. The Force-Velocity Relationship and the one-repetition-maximum load in the dominant and non-dominant leg were obtained in 24 male sports sciences students by a progressive protocol. Additionally, the maximum voluntary contraction (MVC) of the knee extensor muscles was recorded. Individual Force-Velocity Relationships were obtained by the linear, quadratic polynomial and exponential regression models. Although the adjusted coefficients of determination of all three models were high, the polynomial model's coefficient was slightly but significantly higher than the rest of the models (p < 0.05), while the standard error of estimate was slightly higher for the linear than for polynomial model (p = 0.001). MVC was underestimated by F 0 calculated from the linear and polynomial models, while the maximum power was accurately estimated by the linear model. In summary, while the polynomial model revealed somewhat better fit, the linear model more accurately estimates the maximum power and provides the parameters of apparent physiological meaning. Therefore, we recommend using the linear model in research and routine testing of mechanical capacities of knee extensors.
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selective effects of different fatigue protocols on the function of upper body muscles assessed through the Force Velocity Relationship
European Journal of Applied Physiology, 2018Co-Authors: Amador Garciaramos, Paulino Padial, Belen Feriche, Alejandro Torrejon, Antonio J Moralesartacho, Alejandro Perezcastilla, Slobodan JaricAbstract:Purpose This study explored the feasibility of the Force–Velocity Relationship (F–V) to detect the acute effects of different fatigue protocols on the selective changes of the maximal capacities of upper body muscles to produce Force, Velocity, and power.
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selective effects of different fatigue protocols on the function of upper body muscles assessed through the Force Velocity Relationship
European Journal of Applied Physiology, 2018Co-Authors: Amador Garciaramos, Paulino Padial, Belen Feriche, Alejandro Torrejon, Antonio J Moralesartacho, Alejandro Perezcastilla, Slobodan JaricAbstract:This study explored the feasibility of the Force–Velocity Relationship (F–V) to detect the acute effects of different fatigue protocols on the selective changes of the maximal capacities of upper body muscles to produce Force, Velocity, and power. After determining the bench press one-repetition maximum (1RM), participants’ F–V Relationships were assessed during the bench press throw exercise on five separate sessions after performing one of the following fatiguing protocols: 60%1RM failure, 60%1RM non-failure, 80%1RM failure, 80%1RM non-failure, and no-fatigue. In the non-failure protocols, participants performed half the maximum number of repetitions than in their respective failure protocols. The main findings revealed that (1) all F–V Relationships were highly linear (median r = 0.997 and r = 0.982 for averaged across participants and individual data, respectively), (2) the fatiguing protocols were ranked based on the magnitude of power loss as follows: 60%1RM failure > 80%1RM failure > 60%1RM non-failure > 80%1RM non-failure, while (3) the assessed maximum Force and Velocity outputs showed a particularly prominent reduction in the protocols based on the lowest and highest levels of fatigue (i.e., 80%1RM non-failure and 60%1RM failure), respectively. The results support the use of F–V to assess the effects of fatigue on the distinctive capacities of the muscles to produce Force, Velocity, and power output while performing multi-joint tasks, while the assessed maximum Force and Velocity capacities showed a particularly prominent reduction in the protocols based on the lowest and highest levels of fatigue (i.e., 80%1RM non-failure and 60%1RM failure), respectively.
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Force Velocity Relationship of leg muscles assessed with motorized treadmill tests two Velocity method
Gait & Posture, 2017Co-Authors: Slobodanka Dobrijevic, Sasa Djuric, Vladimir Ilic, Slobodan JaricAbstract:Linear regression models applied on Force (F) and Velocity (V) data obtained from loaded multi-joint functional movement tasks have often been used to assess mechanical capacities of the tested muscles. The present study aimed to explore the properties of the F-V Relationship of leg muscles exerting the maximum pulling F at a wide range of V on a standard motorized treadmill. Young and physically active male and female subjects (N=13+15) were tested on their maximum pulling F exerted horizontally while walking or running on a treadmill set to 8 different velocities (1.4-3.3m/s). Both the individual (median R=0.935) and averaged across the subjects F-V Relationships (R=0.994) proved to be approximately linear and exceptionally strong, while their parameters depicting the leg muscle capacities for producing maximum F, V, and power (P; proportional to the product of F and V) were highly reliable (0.84
Amador Garciaramos - One of the best experts on this subject based on the ideXlab platform.
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the Force Velocity Relationship obtained during the squat jump exercise is meaningfully influenced by the initial knee angle
Sports Biomechanics, 2020Co-Authors: Danica Janicijevic, Alejandro Perezcastilla, Olivera M Knezevic, Pierre Samozino, Dragan M Mirkov, Milos Petrovic, Amador GarciaramosAbstract:This study aimed to compare the magnitude of the Force-Velocity (F-V) Relationship parameters (maximum Force [F0], maximum Velocity [V0], F-V slope, and maximum power [Pmax]) between the squat jump...
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Force Velocity Relationship in the countermovement jump exercise assessed by different measurement methods
Journal of Human Kinetics, 2019Co-Authors: Amador Garciaramos, Paulino Padial, Antonio J Moralesartacho, Alejandro Perezcastilla, Blanca De La Fuente, Filipa Almeida, Juan Bonitchgongora, Belen FericheAbstract:This study aimed to compare Force, Velocity, and power output collected under different loads, as well as the Force-Velocity (F-V) Relationship between three measurement methods. Thirteen male judokas were tested under four loading conditions (20, 40, 60, and 80 kg) in the countermovement jump (CMJ) exercise, while mechanical output data were collected by three measurement methods: the Samozino's method (SAM), a Force platform (FP), and a linear Velocity transducer (LVT). The variables of the linear F-V Relationship (maximum Force [F0], maximum Velocity [V0], F-V slope, and maximum power [P0]) were determined. The results revealed that (1) the LVT overestimated the mechanical output as compared to the SAM and FP methods, especially under light loading conditions, (2) the SAM provided the lowest magnitude for all mechanical output, (3) the F-V Relationships were highly linear either for the SAM (r = 0.99), FP (r = 0.97), and LVT (r = 0.96) methods, (4) the F-V slope obtained by the LVT differed with respect to the other methods due to a larger V0 (5.28 ± 1.48 m·s-1) compared to the SAM (2.98 ± 0.64 m·s-1) and FP (3.06 ± 0.42 m·s-1), and (5) the methods were significantly correlated for F0 and P0, but not for V0 or F-V slope. These results only support the accuracy of the SAM and FP to determine the F-V Relationship during the CMJ exercise. The very large correlations of the SAM and LVT methods with respect to the FP (presumed gold-standard) for the mean values of Force, Velocity and power support their concurrent validity for the assessment of mechanical output under individual loads.
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effect of different types of loads on the Force Velocity Relationship obtained during the bench press throw exercise
Journal of Strength and Conditioning Research, 2019Co-Authors: Marko Cosic, Olivera M Knezevic, Aleksandar Nedeljkovic, Sasa Djuric, Milena Z Zivkovic, Amador GarciaramosAbstract:Cosic, M, Knezevic, OM, Nedeljkovic, A, Djuric, S, Zivkovic, MZ, and Garcia-Ramos, A. 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 [F0], Velocity [V0], and power [Pmax]) between the different types of loads, and (c) to explore the concurrent validity of F0 with traditional measures of maximal strength. The F-V Relationships of 15 physically active men (age: 20.9 ± 2.0 years, bench press 1 repetition maximum relative to body mass: 1.20 ± 0.10 kg·kg) 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 (Fiso) and the 1RM were also assessed. The individual F-V Relationships were highly linear regardless of the type of load considered (median r [range] = 0.98 [0.94, 1.00]). The W + I load provided the largest value of F0 (972 ± 45 N; 6.0 and 14.6% higher than W and I, respectively), the I load the largest value of V0 (2.99 ± 0.34 m·s; 40.4 and 20.1% higher than W and W + I, respectively), and the W load the lowest value of Pmax (501 ± 46 W; -22.7 and -17.1% lower than I and W + I, respectively). The F0 obtained from the W load presented the highest association with Fiso and 1RM values (r > 0.90). The W + I load and the I load should be recommended to work closer to the F0 and V0 capacities, respectively. However, the W load should be recommended to assess maximal strength capacity through the value of F0.
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intermittent resistance training at moderate altitude effects on the Force Velocity Relationship isometric strength and muscle architecture
Frontiers in Physiology, 2018Co-Authors: Antonio J Moralesartacho, Amador Garciaramos, Paulino Padial, Alejandro Perezcastilla, Javier Arguellescienfuegos, Blanca De La Fuente, Belen FericheAbstract:Intermittent hypoxic resistance training (IHRT) may help to maximize the adaptations following resistance training, although conflicting evidence is available. The aim of this study was to explore the influence of moderate altitude on the functional, neural and muscle architecture responses of the quadriceps muscles following a power-oriented IHRT intervention. Twenty-four active males completed two 4-week consecutive training blocks comprising general strengthening exercises (weeks 1-4) and power-oriented resistance training (weeks 5-8). Training sessions were conducted twice a week at moderate altitude (2320 m; IHRT, n = 13) or normoxia (690 m; NT, n = 11). Training intensity during the second training block was set to the individual load corresponding to a barbell mean propulsive Velocity of 1 m·s-1. Pre-post assessments, performed under normoxic conditions, comprised quadriceps muscle architecture (thickness, pennation angle and fascicle length), isometric maximal (MVF) and explosive strength, and voluntary muscle activation. Dynamic strength performance was assessed through the Force-Velocity Relationship (F0, V0, P0) and a repeated CMJ test (CMJ15MP). Region-specific muscle thickness changes were observed in both training groups (p < 0.001, η2G = 0.02). A small opposite trend in pennation angle changes was observed (ES [90% CI]: -0.33 [-0.65, -0.01] vs. 0.11 [-0.44, 0.6], in the IHRT and NT group, respectively; p = 0.094, η2G = 0.02). Both training groups showed similar improvements in MVF (ES: 0.38 [0.20, 0.56] vs. 0.55 [0.29, 0.80], in the IHRT and NT group, respectively; p = 0.645, η2G < 0.01), F0 (ES: 0.41 [-0.03, 0.85] vs. 0.52 [0.04, 0.99], in the IHRT and NT group, respectively; p = 0.569, η2G < 0.01) and P0 (ES: 0.53 [0.07, 0.98] vs. 0.19 [-0.06, 0.44], in the IHRT and NT group, respectively; p = 0.320, η2G < 0.01). No meaningful changes in explosive strength performance were observed. In conclusion, contrary to earlier adverse associations between altitude and resistance-training muscle adaptations, similar anatomical and functional muscle strength responses can be achieved in both environmental conditions. The observed region-specific muscle thickness changes may encourage further research on the potential influence of IHRT on muscle morphological changes.
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selective effects of different fatigue protocols on the function of upper body muscles assessed through the Force Velocity Relationship
European Journal of Applied Physiology, 2018Co-Authors: Amador Garciaramos, Paulino Padial, Belen Feriche, Alejandro Torrejon, Antonio J Moralesartacho, Alejandro Perezcastilla, Slobodan JaricAbstract:Purpose This study explored the feasibility of the Force–Velocity Relationship (F–V) to detect the acute effects of different fatigue protocols on the selective changes of the maximal capacities of upper body muscles to produce Force, Velocity, and power.
Urs Boutellier - One of the best experts on this subject based on the ideXlab platform.
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the generalized Force Velocity Relationship explains why the preferred pedaling rate of cyclists exceeds the most efficient one
European Journal of Applied Physiology, 2005Co-Authors: Gotz Kohler, Urs BoutellierAbstract:The most efficient pedaling rate (lowest oxygen consumption) at a workload of 50-300 W has been reported to be in the range of 42-60 rpm. By contrast, most competitive cyclists prefer a pedaling rate of more than 90 rpm. The reason for this difference is still unknown. We assume that the high pedaling rate preferred by cyclists can be explained by the inherent properties of muscle fibers. To obtain statements which do not depend on muscle's cross-section and length, we generalized Hill's characteristic equations where muscle Force and heat liberation are related to shortening Velocity. A pedaling rate of f (etamax) yields to maximal efficiency, whereas the higher pedaling rate f (Pmax) leads to maximal power. The ratio f (Pmax)/f (etamax) between these two pedaling rates ranges from 1.7 to 2.4, and it depends on the muscle's fiber-type composition. In sprints and competitions of very short duration, f (Pmax) is more advantageous because energy supply is not the predominant limiting factor. The price to be paid for the most powerful pedaling rate is lower efficiency and higher energy cost. In longer exercises, economy is more important and the optimal pedaling rate shifts toward f (etamax). We conclude that the optimal pedaling rate, representing the fastest race performance, is not fixed but depends on race duration; it ranges between f (etamax) and f (Pmax). Our results are not only of interest for competitive cyclists but also for investigations using cycle ergometers: maximum power might not be reached by using a pedaling rate near the most efficient one.
A De Haan - One of the best experts on this subject based on the ideXlab platform.
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the Force Velocity Relationship of human adductor pollicis muscle during stretch and the effects of fatigue
The Journal of Physiology, 2000Co-Authors: C J De Ruiter, D A Jones, W J M Didden, A De HaanAbstract:1 We have examined the Force-Velocity characteristics of tetanically activated human adductor pollicis working in vivo, in the fresh and fatigued states. 2 The increase in Force in response to stretch was divided into two major components. The first, steady, component persisted after the stretch and is concluded not to be a function of active cycling cross-bridges because it was not affected by either the Velocity of the stretch or the level of muscle activation. 3 The origin of the second, transient, component of the increased Force seen during stretch is consistent with cross-bridge activity since it increased with increasing Velocity of stretch and was proportional to the level of activation. 4 It is likely that both components of the stretch response make a significant contribution to muscle performance when acting to resist a Force. For the fastest stretch used, the contributions of cross-bridge and non-cross-bridge mechanisms were equal. For the slowest stretch, lasting 10 s and over the same distance, the Force response was attributed almost entirely to non-cross-bridge mechanisms. 5 As a result of acute fatigue (50 % isometric Force loss) there were only small reductions in the non-cross-bridge component of the Force response to stretch, while the cross-bridge component decreased in absolute terms. 6 The transient component of the stretch response increased as a result of fatigue, relative to the isometric Force, while the Force during shortening decreased. The results are consistent with a decrease in cross-bridge turnover in fatigued muscle.
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temperature effect on the Force Velocity Relationship of the fresh and fatigued human adductor pollicis muscle
Pflügers Archiv: European Journal of Physiology, 2000Co-Authors: C J De Ruiter, A De HaanAbstract:The purpose of the present study was to investigate the effect of muscle temperature on the Force/Velocity Relationship of electrically activated human adductor pollicis muscle. Following immersion of the lower arm for 20 min in water baths of four different temperatures, the calculated muscle temperatures were 37.1, 31.4, 25.6 and 22.2°C. At 22.2°C maximal isometric Force was reduced to 79.3±2.9% of the Force obtained at 37.1°C. Q 10 values for the maximal rates of Force development and relaxation, and relaxation times, were about 2.0 between 37.1 and 25.6°C and increased to about 3.5 below 25.6°C. The Q 10 values of the maximal shortening Velocity and the Velocity for maximal power production were similar to those of the isometric speed parameters. The Q 10 for maximal power production increased from 2.0 above 31.4°C to 6.9 between 25.6 and 22.2°C. Following repetitive isometric contractions maximal power production was reduced to 60.0±1.7 and 90.5±1.0% at 37.1 and 22.2°C respectively. Fatigue decreased with cooling of the muscle over the entire (37.1–22.2°C) temperature range.
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temperature effect on the Force Velocity Relationship of the fresh and fatigued human adductor pollicis muscle
Pflügers Archiv: European Journal of Physiology, 2000Co-Authors: C J De Ruiter, A De HaanAbstract:The purpose of the present study was to investigate the effect of muscle temperature on the Force/Velocity Relationship of electrically activated human adductor pollicis muscle. Following immersion of the lower arm for 20 min in water baths of four different temperatures, the calculated muscle temperatures were 37.1, 31.4, 25.6 and 22.2 degrees C. At 22.2 degrees C maximal isometric Force was reduced to 79.3+/-2.9% of the Force obtained at 37.1 degrees C. Q10 values for the maximal rates of Force development and relaxation, and relaxation times, were about 2.0 between 37.1 and 25.6 degrees C and increased to about 3.5 below 25.6 degrees C. The Q10 values of the maximal shortening Velocity and the Velocity for maximal power production were similar to those of the isometric speed parameters. The Q10 for maximal power production increased from 2.0 above 31.4 degrees C to 6.9 between 25.6 and 22.2 degrees C. Following repetitive isometric contractions maximal power production was reduced to 60.0+/-1.7 and 90.5+/-1.0% at 37.1 and 22.2 degrees C respectively. Fatigue decreased with cooling of the muscle over the entire (37.1-22.2 degrees C) temperature range.
Brian R Macintosh - One of the best experts on this subject based on the ideXlab platform.
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is curvature of the Force Velocity Relationship affected by oxygen availability evidence from studies in ex vivo and in situ rat muscles
Pflügers Archiv: European Journal of Physiology, 2020Co-Authors: Anders Meldgaard Kristensen, Brian R Macintosh, Keenan B Macdougall, Kristian OvergaardAbstract:The power of shortening contractions in skeletal muscle is determined by the Force-Velocity Relationship. Fatigue has been reported to either increase or decrease the Force-Velocity curvature depending on experimental circumstances. These discrepant findings may be related to experimental differences in oxygen availability. We therefore investigated how the curvature of the Force-Velocity Relationship in soleus and gastrocnemius rat muscles is affected during fatigue, in both an ex vivo setup without an intact blood perfusion and in an in situ setup with an intact blood perfusion. Furthermore, we investigated the effect of reduced oxygen concentrations and reduced diffusion distance on the curvature of the Force-Velocity Relationship in ex vivo muscles, where muscle oxygen uptake relies on diffusion from the incubation medium. Muscles were electrically stimulated to perform repeated shortening contractions and Force-Velocity curves were determined in rested and fatigued conditions. The curvature increased during fatigue in the soleus muscles (both in situ and ex vivo), and decreased for the gastrocnemius muscles (in situ) or remained unchanged (ex vivo). Furthermore, under ex vivo conditions, neither reduced oxygen concentrations nor reduced diffusion distance conferred any substantial effect on the Force-Velocity curvature. In contrast, reduced oxygen availability and increased diffusion distance did increase the loss of maximal power during fatigue, mainly due to additional decreases in isometric Force. We conclude that oxygen availability does not influence the fatigue-induced changes in Force-Velocity curvature. Rather, the observed variable fatigue profiles with regard to changes in curvature seem to be linked to the muscle fiber-type composition.
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Force Velocity Relationship during isometric and isotonic fatiguing contractions
Journal of Applied Physiology, 2018Co-Authors: Andrea N Devrome, Brian R MacintoshAbstract:The Force-Velocity Relationship was captured while fatigue was maintained at a constant level during isometric and dynamic contractions. The curvature of the Force-Velocity Relationship was less cu...
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calculation of muscle maximal shortening Velocity by extrapolation of the Force Velocity Relationship afterloaded versus isotonic release contractions
Canadian Journal of Physiology and Pharmacology, 2010Co-Authors: Travis Saunderst J J Saunders, Sharon R Bullimore, Walter Herzogw Herzog, Brian R MacintoshAbstract:The maximal shortening Velocity of a muscle (Vmax) provides a link between its macroscopic properties and the underlying biochemical reactions and is altered in some diseases. Two methods that are ...
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the biphasic Force Velocity Relationship in whole rat skeletal muscle in situ
Journal of Applied Physiology, 2007Co-Authors: Andrea N Devrome, Brian R MacintoshAbstract:Edman has reported that the Force-Velocity Relationship (FVR) departs from Hill's classic hyperbola near 0.80 of measured isometric Force (J Physiol 404: 301–321, 1988). The purpose of this study w...