velocity across sets. 3 Therefore, this style of acute training may not be ideal when aiming to maintain power, as demonstrated in the jump squat, 4 , 5 back squat, 1 , 6 and weight-lifting exercises. 7 , 8 Of interest, is the manipulation of training variables, such as rest time, that may reduce the
Justin J. Merrigan, James J. Tufano, Jonathan M. Oliver, Jason B. White, Jennifer B. Fields and Margaret T. Jones
Caleb D. Bazyler, Satoshi Mizuguchi, Ashley A. Kavanaugh, John J. McMahon, Paul Comfort and Michael H. Stone
, and peak power allometrically scaled for body mass (relative peak power [PPa] = W·kg −0.67 ). In addition, player’s back squat 1-RM was estimated from Epley’s 17 equation using player’s heaviest set of 3 repetitions during the back squat from week 2 training. Methodology Training Training was
Alasdair Strokosch, Loic Louit, Laurent Seitz, Richard Clarke and Jonathan D. Hughes
]: age = 21.4 [2.5] y; height = 181.3 [8.3] cm; body mass = 91.9 [8.8] kg; 1RM back squat/BM = 1.59 [0.21]; 1RM deadlift/BM = 2.11 [0.25]; ≥3-y resistance training experience) volunteered to complete 2 familiarization sessions and 3 experimental sessions. All subjects were informed of the aims, benefits
Simon Gavanda, Stephan Geisler, Oliver Jan Quittmann and Thorsten Schiffer
variables in this study consisted of 2 different training forms (BLOCK and DUP) and 14 dependent variables. Back squat (BS) and bench press (BP) 1RM, as measurements of strength. Bioelectrical impedance analysis and ultrasound measures were taken to test for changes in body composition and MM (body mass [BM
Kym J. Williams, Dale W. Chapman, Elissa J. Phillips and Nick Ball
RU athletes and the BB and VB athletes. Strength Assessment Each athlete completed a 3-repetition maximum (3RM) parallel bi-lateral back squat assessment to estimate lower-body strength 48 hours prior to kinetic and kinematic CMJ assessment. The 3RM back squat strength was performed in a squat cage
Jason Lake, Mike Lauder, Neal Smith and Kathleen Shorter
This study compared differences between ballistic jump squat (B) and nonballistic back squat (NB) force, velocity, power, and relative acceleration duration, and the effect that the method used to identify the positive lifting phase had on these parameters. Ground reaction force and barbell kinematics were recorded from 30 resistance trained men during B and NB performance with 45% 1RM. Force, velocity, and power was averaged over positive lifting phases identified using the traditional peak barbell displacement (PD) and positive impulse method. No significant differences were found between B and NB mean force, and mean power, but B mean velocity was 14% greater than the NB equivalent. Positive impulse mean force was 24% greater than PD mean force, and B relative acceleration duration was 8.6% greater than the NB equivalent when PD was used to identify the end of the positive lifting phase. These results challenge common perceptions of B superiority for power development.
James J. Tufano, Jenny A. Conlon, Sophia Nimphius, Lee E. Brown, Harry G. Banyard, Bryce D. Williamson, Leslie G. Bishop, Amanda J. Hopper and G. Gregory Haff
To determine the effects of intraset rest frequency and training load on muscle time under tension, external work, and external mechanical power output during back-squat protocols with similar changes in velocity.
Twelve strength-trained men (26.0 ± 4.2 y, 83.1 ± 8.8 kg, 1.75 ± 0.06 m, 1.88:0.19 one-repetition-maximum [1RM] body mass) performed 3 sets of 12 back squats using 3 different set structures: traditional sets with 60% 1RM (TS), cluster sets of 4 with 75% 1RM (CS4), and cluster sets of 2 with 80% 1RM (CS2). Repeated-measures ANOVAs were used to determine differences in peak force (PF), mean force (MF), peak velocity (PV), mean velocity (MV), peak power (PP), mean power (MP), total work (TW), total time under tension (TUT), percentage mean velocity loss (%MVL), and percentage peak velocity loss (%PVL) between protocols.
Compared with TS and CS4, CS2 resulted in greater MF, TW, and TUT in addition to less MV, PV, and MP. Similarly, CS4 resulted in greater MF, TW, and TUT in addition to less MV, PV, and MP than TS did. There were no differences between protocols for %MVL, %PVL, PF, or PP.
These data show that the intraset rest provided in CS4 and CS2 allowed for greater external loads than with TS, increasing TW and TUT while resulting in similar PP and %VL. Therefore, cluster-set structures may function as an alternative method to traditional strength- or hypertrophy-oriented training by increasing training load without increasing %VL or decreasing PP.
Glyn Howatson, Raphael Brandon and Angus M. Hunter
There is a great deal of research on the responses to resistance training; however, information on the responses to strength and power training conducted by elite strength and power athletes is sparse.
To establish the acute and 24-h neuromuscular and kinematic responses to Olympic-style barbell strength and power exercise in elite athletes.
Ten elite track and field athletes completed a series of 3 back-squat exercises each consisting of 4 × 5 repetitions. These were done as either strength or power sessions on separate days. Surface electromyography (sEMG), bar velocity, and knee angle were monitored throughout these exercises and maximal voluntary contraction (MVC), jump height, central activation ratio (CAR), and lactate were measured pre, post, and 24 h thereafter.
Repetition duration, impulse, and total work were greater (P < .01) during strength sessions, with mean power being greater (P < .01) after the power sessions. Lactate increased (P < .01) after strength but not power sessions. sEMG increased (P < .01) across sets for both sessions, with the strength session increasing at a faster rate (P < .01) and with greater activation (P < .01) by the end of the final set. MVC declined (P < .01) after the strength and not the power session, which remained suppressed (P < .05) 24 h later, whereas CAR and jump height remained unchanged.
A greater neuromuscular and metabolic demand after the strength and not power session is evident in elite athletes, which impaired maximal-force production for up to 24 h. This is an important consideration for planning concurrent athlete training.
Christina Carr, John J. McMahon and Paul Comfort
Previous research has investigated changes in athletes’ strength, power, and speed performances across the competitive season of many sports, although this has not been explored in cricketers. The aim of this study was to investigate changes in lower-body strength and jump and sprint performances across an English county cricket season.
Male cricketers (N = 12; age 24.4 ± 2.3 y, body mass 84.3 ± 9.9 kg, height 184.1 ± 8.1 cm) performed countermovement jumps (CMJs) and 20-m sprints on 4 separate occasions and back-squat strength testing on 3 separate occasions across a competitive season.
Both absolute (12.9%, P = .005, effect size [ES] = 0.53) and relative lower-body strength (15.8%, P = .004, ES = 0.69) and CMJ height (5.3%, P = .037, ES = 0.42) improved significantly over the preseason training period, although no significant change (1.7%, P > .05) in sprint performance was observed. In contrast, absolute (14.3%, P = .001, ES = 0.72) and relative strength (15.0%, P = .001, ES = 0.77), CMJ height (4.2%, P = .023, ES = 0.40), and sprint performance (3.8%, P = .012, ES = 0.94) declined significantly across the season.
The results of this study show that neither the demands of the competitive cricket season nor current in-season training practices provide a sufficient stimulus to maintain strength, jump, and sprint performances in these cricketers. Therefore, coaches should implement a more-frequent, higher-load strength-training program across the competitive cricket season.
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.