scholarly journals Where does the One-Repetition Maximum Exist on the Force-Velocity Relationship in Squat?

2017 ◽  
Vol 38 (13) ◽  
pp. 1035-1043 ◽  
Author(s):  
Jean Rivière ◽  
Jérémy Rossi ◽  
Pedro Jimenez-Reyes ◽  
Jean-Benoit Morin ◽  
Pierre Samozino

AbstractThe aim was to determine the position of the one-repetition maximum (1RM) squat point on the force-velocity (F-V) relationship obtained during squat jump (SJ). Ten healthy athletes performed a 1RM squat during which ground reaction force and lower-limb extension velocity were measured, and six loaded SJs to determine individual F-V relationship. The goodness of fit of the linear F-V relationship with or without the 1RM point was tested. The vertical and horizontal coordinates were determined relative to the theoretical maximal force (F0) and the highest loaded SJ (load of 44.5±4.6% 1RM). The goodness of fit of the individual F-V relationship did not differ with or without the 1RM condition, even if the 1RM point was slightly below the curve (−5±5%, P=0.018). The 1RM point can be considered as a point of the F-V relationship. The velocity (0.22±0.05 m.s−1) of the 1RM point corresponded to ~30% of the velocity reached during the highest loaded SJ. The force developed in the 1RM condition was ~16% higher than during the highest loaded SJ and ~11% lower than F0. This finding underlines the difference between F0 and the 1RM condition.

Kinesiology ◽  
2021 ◽  
Vol 53 (2) ◽  
pp. 215-225
Author(s):  
Ricardo Berton ◽  
Marcos Soriano ◽  
Demostenys David da Silva ◽  
Marcel Lopes dos Santos ◽  
Gustavo Teixeira ◽  
...  

The study investigated the concurrent validity and reliability of the load-velocity relationship to predict the one-repetition maximum (1RM) of the power clean from the knee (PCK), high pull from the knee (HPK), and mid-thigh clean pull (MTCP). For each exercise, 12 participants performed two 1RM sessions tests and two sessions to measure the barbell’s load-velocity relationship at 30, 45, 60, 75, and 90% of 1RM. The velocity recorded at each load was used to establish the linear regression equation and, consequently, to predict 1RM value. A low validity between the 1RM direct test and predicted 1RM was observed for PCK (typical error [TE]=3.96 to 4.50 kg, coefficient of variation [CV]=4.68 to 5.27%, effect size [ES]=-0.76 to -0.58, Bland-Altman bias [BAB]=9.83 to 11.19 kg), HPK (TE=4.58 to 5.82 kg, CV=6.44 to 8.14%, ES=-0.40 to -0.39, BAB=3.52 to 4.17 kg), and MTCP (TE=6.33 to 8.08 kg, CV=4.78 to 6.16%, ES=-0.29 to -0.19, BAB=3.98 to 6.17 kg). Adequate reliability was observed for the 1RM direct test and for the predicted 1RM. However, based on Bland-Altman limits of agreement, lower measurement errors were obtained for the 1RM direct test in comparison to the predicted 1RM for all the exercises. In conclusion, the load-velocity relationship was not able to predict 1RM values with high accuracy in the PCK, HPK, and MTCP. Moreover, the 1RM direct test was the most reliable for PCK, HPK and MTCP.


2016 ◽  
Vol 32 (2) ◽  
pp. 178-185 ◽  
Author(s):  
Amador García-Ramos ◽  
Slobodan Jaric ◽  
Paulino Padial ◽  
Belén Feriche

This study aimed to (1) evaluate the linearity of the force–velocity relationship, as well as the reliability of maximum force (F0), maximum velocity (V0), slope (a), and maximum power (P0); (2) compare these parameters between the traditional and ballistic bench press (BP); and (3) determine the correlation of F0 with the directly measured BP 1-repetition maximum (1RM). Thirty-two men randomly performed 2 sessions of traditional BP and 2 sessions of ballistic BP during 2 consecutive weeks. Both the maximum and mean values of force and velocity were recorded when loaded by 20–70% of 1RM. All force–velocity relationships were strongly linear (r > .99). While F0 and P0 were highly reliable (ICC: 0.91–0.96, CV: 3.8–5.1%), lower reliability was observed for V0 and a (ICC: 0.49–0.81, CV: 6.6–11.8%). Trivial differences between exercises were found for F0 (ES: < 0.2), however the a was higher for the traditional BP (ES: 0.68–0.94), and V0 (ES: 1.04–1.48) and P0 (ES: 0.65–0.72) for the ballistic BP. The F0 strongly correlated with BP 1RM (r: 0.915–0.938). The force–velocity relationship is useful to assess the upper body maximal capabilities to generate force, velocity, and power.


2018 ◽  
Vol 124 (4) ◽  
pp. 831-839 ◽  
Author(s):  
Briar L. Rudsits ◽  
Will G. Hopkins ◽  
Christophe A. Hautier ◽  
David M. Rouffet

Force-velocity tests performed on stationary cycle ergometers are widely used to assess the torque- and power-generating capacities of the lower limbs. The aim of this study was to identify how testing and modeling procedures influence the assessment of individual torque-cadence and power-cadence relationships. Seventeen males completed 62 ± 16 pedal cycles from six 6-s all-out efforts interspersed with 5 min of rest. True measures of maximal power for a particular cadence were obtained for 24 ± 3 pedal cycles, while power was only 94 ± 3% of the true maximum in 19 ± 5 pedal cycles. Pedal cycles showing maximal levels of power also displayed higher levels of electromyography (EMG: 89 ± 7 vs . 87 ± 7%) and coactivation (34 ± 11 vs . 31 ± 10 arbitrary units), as well as lower variability in crank torque and EMG profiles. Compared with the linear and second-order polynomial models that are traditionally used, a better goodness of fit was obtained when the torque-cadence and power-cadence relationships were predicted using second- and third-order polynomials, respectively. The later modeling procedures also revealed an asymmetry in the power-cadence relationship in most participants (i.e., 15 out of 17) and provided a better estimation of maximal cadence [Cmax: 214 ± 20 revolutions/min (rpm)] from the x-intercept of power-cadence relationships (C0: 214 ± 14 rpm). Therefore, we recommend predicting the individual shapes of torque- and power-cadence relationships using second- and third-order polynomial regressions after having selected pedal cycles during which true measures of cadence-specific maximal power were recorded. NEW & NOTEWORTHY This study is the first to demonstrate that suboptimal activation of the lower limb muscles accompanied reductions in cadence-specific levels of torque and power produced during a force-velocity test performed on a stationary cycle ergometer. This research is also the first to show that, in most noncyclist participants, torque-cadence relationships are not linear, whereas power-cadence relationships display asymmetric shapes, with power production decreasing rapidly when cadence increases beyond 180 revolutions/min.


2019 ◽  
Vol 59 (1) ◽  
pp. 44-68
Author(s):  
Nikolas Nagy ◽  
Miroslav Holienka ◽  
Matej Babic ◽  
Jakub Michálek ◽  
Egon Kunzmann

Summary The aim of this research was to make reference to the difference in heart rate values (HR) of soccer players in small-sided games (SSG) with various content focus. We assumed that the aim at the content in small-sided games would significantly affect the HR values of participating soccer players. The research group was comprised of players (n = 6) of the soccer club FK DAC 1904 Dunajská Streda (U15) at the age of 14 ± 0.7 years. The HR values were evaluated on the basis of collected data, which we obtained using sport testers and special software POLAR TEAM2. In order to find out the statistical significance of the difference in HR was used the One-Way ANOVA and the Bonferroni post hoc test. The level of statistical significance was set at 5 %. We found out that by the change of the small-sided game’s content focus, the internal reaction of players’ organism to training load was at different level. In the SSG3, with the emphasis on the improvement of individual’s final offensive game activity – shooting, was recorded the highest achieved HRavg value of the monitored players (181.83 ±7.11 beats.min−1). This form of the SSG was the most intense. However, there were no significant differences in HR values among the individual forms of the SSG. Our recommendation is to employ in the systematic training process small forms of small-sided games with various content focus, because by the means of it we can adequately prepare the players for the match load itself.


2018 ◽  
Vol 13 (3) ◽  
pp. 326-331 ◽  
Author(s):  
Amador García-Ramos ◽  
Francisco Luis Pestaña-Melero ◽  
Alejandro Pérez-Castilla ◽  
Francisco Javier Rojas ◽  
Guy Gregory Haff

Purpose: To compare the load–velocity relationship between 4 variants of the bench-press (BP) exercise. Methods: The full load–velocity relationship of 30 men was evaluated by means of an incremental loading test starting at 17 kg and progressing to the individual 1-repetition maximum (1RM) in 4 BP variants: concentric-only BP, concentric-only BP throw (BPT), eccentric-concentric BP, and eccentric-concentric BPT. Results: A strong and fairly linear relationship between mean velocity (MV) and %1RM was observed for the 4 BP variants (r2 > .96 for pooled data and r2 > .98 for individual data). The MV associated with each %1RM was significantly higher in the eccentric-concentric technique than in the concentric-only technique. The only significant difference between the BP and BPT variants was the higher MV with the light to moderate loads (20–70%1RM) in the BPT using the concentric-only technique. MV was significantly and positively correlated between the 4 BP variants (r = .44–.76), which suggests that the subjects with higher velocities for each %1RM in 1 BP variant also tend to have higher velocities for each %1RM in the 3 other BP variants. Conclusions: These results highlight the need for obtaining specific equations for each BP variant and the existence of individual load–velocity profiles.


2011 ◽  
Vol 26 (4) ◽  
pp. 195-199 ◽  
Author(s):  
James Hackney ◽  
Sara Brummel ◽  
Dana Becker ◽  
Aubrey Selbo ◽  
Sandra Koons ◽  
...  

Our objective in this study was to compare stiffness of bilateral lower extremities (LEs) in ballet dancers performing sauté on a low-stiffness “sprung floor” to that during the same movement on a high-stiffness floor (wood on concrete). LE stiffness was calculated as the ratio of vertical ground reaction force (in kN) to compression of the lower limb (in meters). Seven female dancers were measured for five repetitions each at the point of maximum leg compression while performing sauté on both of the surfaces, such that 43 ms of data were represented for each trial. The stiffness of bilateral LEs at the point of maximum compression was higher by a mean difference score of 2.48±2.20 kN/m on the low-stiffness floor compared to a high-stiffness floor. Paired t-test analysis of the difference scores yielded a one-tailed probability of 0.012. This effect was seen in six out of seven participants (one participant showed no difference between floor conditions). The finding of increased stiffness of the LEs in the sprung floor condition suggests that some of the force of landing the jump was absorbed by the surface, and therefore did not need to be absorbed by the participants’ LEs themselves. This in turn implies that a sprung dance floor may help to prevent dance-related injuries.


2020 ◽  
Vol 25 (5) ◽  
pp. 258-262
Author(s):  
Lewis J. Vizard ◽  
Gareth Peden ◽  
Maximilian M. Wdowski

The aim of this study was to examine if lower-limb kinetic and kinematic asymmetries are transferred between sprint running and countermovement jumps in a group of university Rugby Union players. Eight university Rugby Union players (20.3 ± 1.6 years) participated in the study. Three-dimensional kinematic and force platform data recorded sprint runs and countermovement jumps. Across the two movements there was a substantial and moderate level of agreement for the ankle range of motion and peak normalized ground reaction force, respectively. No significant differences were observed between interlimb kinematic and kinetic variables at the group level. Lower-limb asymmetries may be transferred across dynamic movements and are present at the individual level.


2018 ◽  
Vol 27 (4) ◽  
pp. 319-326 ◽  
Author(s):  
Guillermo Mendez-Rebolledo ◽  
Rodrigo Ramirez-Campillo ◽  
Eduardo Guzman-Muñoz ◽  
Valeska Gatica-Rojas ◽  
Alexis Dabanch-Santis ◽  
...  

Context: Kinesio taping is commonly used in sports and rehabilitation settings with the aim of prevention and treatment of musculoskeletal injuries. However, limited evidence exists regarding the effects of 24 and 72 hours of kinesio taping on trunk and lower limb neuromuscular and kinetic performance during a vertical jump. Objective: The purpose of this study was to analyze the short-term effects of kinesio taping on height and ground reaction force during a vertical jump, in addition to trunk and lower limb muscle latency and recruitment order. Design: Single-group pretest–posttest. Setting: University laboratory. Participants: Twelve male athletes from different sports (track and field, basketball, and soccer). Interventions: They completed a single squat and countermovement jump at basal time (no kinesio taping), 24, and 72 hours of kinesio taping application on the gluteus maximus, biceps femoris, rectus femoris, gastrocnemius medialis, and longissimus. Main Outcome Measures: Muscle onset latencies were assessed by electromyography during a squat and countermovement jump, in addition to measurements of the jump height and normalized ground reaction force. Results: The kinesio taping had no effect after 24 hours on either the countermovement or squat jump. However, at 72 hours, the kinesio taping increased the jump height (P = .02; d = 0.36) and normalized ground reaction force (P = .001; d = 0.45) during the countermovement jump. In addition, 72-hour kinesio taping reduced longissimus onset latency (P = .03; d = 1.34) and improved muscle recruitment order during a countermovement jump. Conclusions: These findings suggest that kinesio taping may improve neuromuscular and kinetic performance during a countermovement jump only after 72 hours of application on healthy and uninjured male athletes. However, no changes were observed on a squat jump. Future studies should incorporate a control group to verify kinesio taping’s effects and its influence on injured athletes.


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