, objective/physiological through heart rate or subjective/psychological through rating of perceived exertion [RPE]). Furthermore, these measures can then be calculated to represent absolute load (eg, 1-wk load) or relative load (eg, acute:chronic workload ratio). Research of AFL players has investigated load and injury through
Timothy J.H. Lathlean, Paul B. Gastin, Stuart V. Newstead and Caroline F. Finch
David Rodríguez-Osorio, Oliver Gonzalo-Skok and Fernando Pareja-Blanco
involving several relative loads on soccer players’ physical performance. We hypothesized that resisted COD training would lead to superior improvement at COD, sprint, and jump performance in comparison with unresisted COD training. Methods Participants Fifty-four male soccer players (anthropometric
Jeffrey M. McBride, Tony R. Larkin, Andrea M. Dayne, Tracie L. Haines and Tyler J. Kirby
The purpose of this investigation was to determine the effect of stable and unstable conditions on one repetition maximum strength and muscle activity during dynamic squatting using absolute and relative loading.
Ten recreationally weight-trained males participated in this study (age = 24.1 ± 2.0 y, height = 178.0 ± 5.6 cm, body mass = 83.7 ± 13.4 kg, 1RM/body mass = 1.53 ± 0.31), which involved two laboratory sessions separated by 1 wk. Linear position transducers were used to track bar displacement while subjects stood on a force plate for all trials. Vastus lateralis (VL), biceps femoris (BF) and erector spinae (L1) muscle activity (average integrated EMG [IEMG]) was also recorded during all trials. During the frst session subjects complete a one repetition maximum test in a stable dynamic squat (S1RM = 128.0 ± 31.4 kg) and an unstable dynamic squat (U1RM = 83.8 ± 17.3 kg) in a randomized order with a 30-min rest period between conditions. The second session consisted of the performance of three trials each for 12 different conditions (unstable and stable squats using three different absolute loads [six conditions] and unstable and stable squats using three different relative loads [six conditions]).
Results revealed a statistically significant difference between S1RM and U1RM values (P < .05). The stable trials resulted in the same or a significantly higher value for VL, BF and L1 muscle activity in comparison with the unstable trials for all twelve conditions.
Unstable squatting is of equal or less (depending on the loading condition) benefit to improving or maximizing muscle activity during resistance exercise.
Bret Contreras, Andrew D. Vigotsky, Brad J. Schoenfeld, Chris Beardsley and John Cronin
Front, full, and parallel squats are some of the most popular squat variations. The purpose of this investigation was to compare mean and peak electromyography (EMG) amplitude of the upper gluteus maximus, lower gluteus maximus, biceps femoris, and vastus lateralis of front, full, and parallel squats. Thirteen healthy women (age = 28.9 ± 5.1 y; height = 164 ± 6.3 cm; body mass = 58.2 ± 6.4 kg) performed 10 repetitions of their estimated 10-repetition maximum of each respective variation. There were no statistical (P = .05) differences between full, front, and parallel squats in any of the tested muscles. Given these findings, it can be concluded that the front, full, or parallel squat can be performed for similar EMG amplitudes. However, given the results of previous research, it is recommended that individuals use a full range of motion when squatting, assuming full range can be safely achieved, to promote more favorable training adaptations. Furthermore, despite requiring lighter loads, the front squat may provide a similar training stimulus to the back squat.
Alejandro Pérez-Castilla, Daniel Jerez-Mayorga, Dario Martínez-García, Ángela Rodríguez-Perea, Luis J. Chirosa-Ríos and Amador García-Ramos
grip width in comparison with the use of a self-selected grip width. In contrast, when the same relative loads are compared, Lockie et al 19 did not found significant differences in the load–power relationship between a close and self-selected grip width. It has also been shown that a narrow grip
Francisco Luis Pestaña-Melero, G. Gregory Haff, Francisco Javier Rojas, Alejandro Pérez-Castilla and Amador García-Ramos
, 10 – 12 The use of movement velocity to predict relative load is justified by the strong relationship that has been observed between mean velocity and %1RM in both upper and lower body exercises performed in a Smith machine. 10 , 13 However, the reliability of mean velocity to predict the 1RM could
Miguel Sánchez-Moreno, David Rodríguez-Rosell, Fernando Pareja-Blanco, Ricardo Mora-Custodio and Juan José González-Badillo
because it affects neuromuscular responses and subsequent adaptations. 2 , 8 Typically, training volume is prescribed using a specific number of repetitions in each exercise set for all subjects. However, the maximal number of repetitions that can be completed against a given relative load (%1RM) shows a
Aitor Iturricastillo, Cristina Granados, Raúl Reina, José Manuel Sarabia, Ander Romarate and Javier Yanci
. The association among BP performance, acceleration, RSA, and CODA could provide information to use BP exercise to improve field performance. Therefore, the aims of this study were (1) to analyze the relationship between MPV and relative load %1RM in the BP exercise to assess the possibility of using
Amador García-Ramos, Alejandro Torrejón, Belén Feriche, Antonio J. Morales-Artacho, Alejandro Pérez-Castilla, Paulino Padial and Guy Gregory Haff
velocity (MV) of the barbell recorded by a linear velocity transducer and the relative load (%1RM) in multijoint machine-based resistance exercises involving both upper- and lower-body muscles. 9 – 13 This strong relationship suggests that exercise intensity can be prescribed on a daily basis by adjusting
Kym J. Williams, Dale W. Chapman, Elissa J. Phillips and Nick Ball
checked for normal distribution and outliers. A 1-way repeated-measures analysis of variance was used to determine whether there was a significant interaction between system or joint power and relative load within each sport, whereas a Bonferroni post hoc analysis was implemented to identify where the