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Power and Impulse Applied During Push Press Exercise
Abstract
The aim of this study was to quantify the load that maximized peak and mean power, as well as impulse applied to these loads, during the push press and to compare them to equivalent jump squat data. Resistance-trained men performed two push press (n = 17; age: 25.4 ± 7.4 years; height: 183.4 ± 5 cm; body mass: 87 ± 15.6 kg) and jump squat (n = 8 of original 17; age: 28.7 ± 8.1 years; height: 184.3 ± 5.5 cm; mass: 98 ± 5.3 kg) singles with 10-90% of their push press and back squat 1 RM, respectively, in 10% 1 RM increments while standing on a force platform. Push press peak and mean power was maximized with 75.3 ± 16.4 and 64.7 ± 20% 1RM, respectively, and impulses applied to these loads were 243 ± 29 N.s and 231 ± 36 N.s. Increasing and decreasing load, from the load that maximized peak and mean power, by 10% and 20% 1RM reduced peak and mean power by 6-15% (p < 0.05). Push press and jump squat maximum peak power (7%, p = 0.08) and the impulse that was applied to the load that maximized peak (8%, p = 0.17) and mean (13%, p = 0.91) power were not significantly different, but push press maximum mean power was significantly greater than the jump squat equivalent (∼9.5%, p = 0.03). The mechanical demand of the push press is comparable to the jump squat and could provide a time-efficient combination of lower-body power and upper-body and trunk strength training.
... It is commonly accepted that load and the type of weightlifting exercise affect exercise kinetics and kinematics (6,7,16,29). Comfort et al. (6,7) reported that when performing the mid-thigh clean pull with 40, 60, 80, 100, 120, and 140% of 1 repetition maximum (1RM) power clean, lighter loads (40-60% 1RM) maximized power, whereas heavier loads (120-140% 1RM) maximized force production (peak force, rate of force development, and impulse). ...
... To the authors' knowledge, there is minimal research exploring the impact of load on the kinetics and kinematics of the push press (PP), push jerk (PJ), and split jerk (SJ). For example, Lake et al. (16) investigated the load that maximized system power and impulse during the PP across incremental loads (10-90% 1RM), whereas Soriano et al. (27) investigated the differences in kinetics (force, power, and impulse) and kinematics (displacement and duration) between the PP, PJ, and SJ performed at a fixed load. However, researchers have not compared the effect of incremental loads and exercise (PP, PJ, and SJ) on kinetics and kinematics, providing a framework to gain a better understanding of the mechanics of each exercise and load selection. ...
... To achieve their lifting goals, an athlete can choose from various strategies. One such strategy is applying a specific amount of force over a longer distance and time, which results in an increase in both work and impulse (16,19,21,23,35). Another strategy is to apply higher forces over a shorter duration or distance, which results in an increase in power (16,19,21,23,35). ...
Soriano, MA, Jiménez-Ormeño, E, Lake, JP, McMahon, JJ, Gallo-Salazar, C, Mundy, P, and Comfort, P. Kinetics and kinematics of the push press, push jerk, and split jerk. J Strength Cond Res 38(8): 1359–1365, 2024—The aim of this study was to explore the kinetics and kinematics across incremental loads with the push press (PP), push jerk (PJ), and split jerk (SJ). Eighteen resistance-trained men performed the 1 repetition maximum (1RM) tests (visit 1) 3–7 days before an incremental loading protocol (60, 75, and 90% 1RM) of the 3 exercises (visit 2). Kinetics and kinematics were derived from force-time data and compared using a repeated-measures analysis of variance with load and exercise as within-subject factors. Dependent variables for the biomechanics assessment were categorized as output (power and impulse), driver (force and work), and strategy (displacement and duration) metrics. The interrepetition reliability was assessed using the intraclass correlation coefficient and coefficient of variation. The PP, PJ, and SJ 1RM performance were 89.7 ± 15.4, 95.6 ± 14.4, and 103.0 ± 16.9 kg, respectively. Driver, strategy, and outcome metrics displayed moderate-to-excellent (intraclass correlation coefficient: 0.58–0.98) reliability with acceptable variability (% coefficient of variation: 2.02–10.00). Increased load resulted in significantly large increases in force, work, displacement, duration, power, and impulse ( p < 0.001, = 0.534–0.903). Exercise selection had a significant and large effect on power, impulse, work, and force ( p < 0.016, = 0.387–0.534). There was a significant and large effect of load × exercise interaction on work, displacement, and duration ( p < 0.019, = 0.158–0.220). Practitioners are encouraged to use heavier loads (90 > 75 > 60% 1RM) during the SJ exercise to maximize output, driver, and strategy kinetics and kinematics.
... These complex, ballistic multi-joint movement patterns require the lifter to generate high forces via rapid extension of the hips, knees, and ankles (i.e., triple extension), transmitting these through the trunk to the upper extremities (213,262), to provide a sufficient impulse to accelerate the barbell overhead. These exercises share similar lower body propulsion kinematics which includes the dip (unweighting and breaking phase of a quick partial squat) and drive/thrust phase (rapid extension of the hips, knees, and plantar flexion of the ankles) (166,167,258,261). The main differences between lifts occur after the lower body propulsion phase regarding the displacement of the barbell and the catch position (258,261). ...
... Interestingly, the loads that maximize power production are generally >70%1RM (52,94,119,152,166,167,180). Therefore, strength and conditioning coaches should consider using the push press, push jerk, and split jerk with loads ≥70%1RM to target the development of Strength-Speed in sporting populations ( Figure 1). ...
Comfort, P, Haff, GG, Suchomel, TJ, Soriano, MA, Pierce, KC, Hornsby, WG, Haff, EE, Sommerfield, LM, Chavda, S, Morris, SJ, Fry, AC, and Stone, MH. National Strength and Conditioning Association position statement on weightlifting for sports performance. J Strength Cond Res XX(X): 000-000, 2022-The origins of weightlifting and feats of strength span back to ancient Egypt, China, and Greece, with the introduction of weightlifting into the Olympic Games in 1896. However, it was not until the 1950s that training based on weightlifting was adopted by strength coaches working with team sports and athletics, with weightlifting research in peer-reviewed journals becoming prominent since the 1970s. Over the past few decades, researchers have focused on the use of weightlifting-based training to enhance performance in nonweightlifters because of the biomechanical similarities (e.g., rapid forceful extension of the hips, knees, and ankles) associated with the second pull phase of the clean and snatch, the drive/thrust phase of the jerk and athletic tasks such as jumping and sprinting. The highest force, rate of force development, and power outputs have been reported during such movements, highlighting the potential for such tasks to enhance these key physical qualities in athletes. In addition, the ability to manipulate barbell load across the extensive range of weightlifting exercises and their derivatives permits the strength and conditioning coach the opportunity to emphasize the development of strength-speed and speed-strength, as required for the individual athlete. As such, the results of numerous longitudinal studies and subsequent meta-analyses demonstrate the inclusion of weightlifting exercises into strength and conditioning programs results in greater improvements in force-production characteristics and performance in athletic tasks than general resistance training or plyometric training alone. However, it is essential that such exercises are appropriately programmed adopting a sequential approach across training blocks (including exercise variation, loads, and volumes) to ensure the desired adaptations, whereas strength and conditioning coaches emphasize appropriate technique and skill development of athletes performing such exercises.
... In ACRO, achieving amplitude during the flight phase [3] requires precise coordination between top and base gymnasts [17]. While top gymnasts jump with a motion similar to the countermovement jump (CMJ), base gymnasts throw, with a push press motion, combining a loaded lower-body countermovement with overhead pressing [18]. CMJ is extensively described using force-time curves [19][20][21][22][23], and the push press using vertical force and velocity-time curves [24]. ...
Coordination refers to the relationship between elements. Likewise, in partner-assisted flight, gymnasts synchronize their movements to optimize performance. This work investigates the individual contribution of each gymnast for a paired task and the influence of pair experience on spatial-temporal variables and interpersonal coordination. Twelve national and international-level pairs performed ten vertical throws in laboratory settings. Data were collected using a motion capture system and processed using Theia Markerless software, v2023.1.0.3160.p14. Pairs were categorized by pair experience. Top gymnast motion was analyzed using global (GCS) and local coordinate systems (LCS), and spatial-temporal and cross-correlation variables were compared between experience levels. The results showed that the top gymnasts’ GCS exhibited the largest amplitudes, while the base and the top’s LCS demonstrated the smallest. More experienced pairs displayed a shorter downward motion (p < 0.001, Effect Size (ES) = 0.67) longer upward motion (p = 0.04, ES = 0.37), smaller time delays in position (p = 0.03, ES = 0.39), and longer time delays in velocity (p = 0.01, ES = 0.47). These findings suggest that top gymnasts’ motion is largely driven by the bases, and pair experience develops anticipation of the partner’s motion and task-specific adaptations. Increased partner training time appears crucial for improving interpersonal coordination.
... Hence, the differences in LIHV-MNRF performance could be attributed to their belonging to the rural or urban area group. To understand the large differences in the relevant elements of performance, was also proposed an analysis based on the impulse, which is defined by the product of instantaneous force and time (Lake et al., 2014) and in the current study, it was computed by using the area under the net force-time curve during the concentric phase of each exercise. The total impulse and the impulse per relevant repetitions are important mechanical parameters that determine the magnitude and rate of motion of the object's load with indications for the power (Knudson, 2009). ...
The study aimed to identify and explain the typical differences in low-intensity high-volume resistance training (LIHV-RT) performances for major muscle groups between rural versus urban young female students to establish the relevant set of quantitative and qualitative resistance training parameters. The study sample included 46 recreational active female students at the Transilvania University of Brașov, (mean ± SD age, 20 ± 1 year; body mass, 60 ± 3 kg; height, 160 ± 4 cm) grouped urban vs. rural. The study used modified resistance exercise machines for the hamstring- and quadricep-group muscles, equipped with a dynamometer and sensors for identifying developed forces and accelerations. A number of 368 tests were performed, representing two attempts for each subject, for knee flexion and knee extension exercises, with two different loads. For the performance analysis some variables were considered: the maximum number of repetition until failure, maximum force developed, maximum acceleration, the duration of the set and the mean time per repetition. The maximum number of repetition to failure shows a significant higher value for rural than urban in case of knee flexion (d = 0.98 [0.32, 1.54] for load 1(L1) and d = 0.65 [0.03, 1.21] for load 2(L2)) and in case of knee extension (d = 1.89 [1.11, 2.48] for L1 and d = 1.67 [0.92, 2.25] for L2). The total duration of the sets shows a significant higher value for rural than urban in case of knee flexion (d = 0.84 [0.19, 1.39] for L2) and in case of knee extension (d = 1.46 [0.74, 2.03] for L1 and d = 1.56 [0.98, 2.14] for L2). Additionally we found differences in the quality of the relevant repetitions execution and in the impulse developed during the LIHV- MNRF sets. The study’s main finding was that there are differences in LIHV-RT performances knee flexion and knee extension antagonistic exercises, between rural and urban female students. We concluded that the obtained results allow teachers to understand the optimal design of RT programs for the different groups of participants, in order to adapt their teaching techniques so that their final objectives are achieved, insisting on particular aspects of the theoretical or practical contents.
... The push press was chosen as the reference exercise because it is a limiting exercise in the WOD. So it may be relativized (75 % 1RM) accordingly using the exercise with the lowest weight lifted [22,23]. ...
CrossFit is characterized by being a standardized training program that improves physical performance through the provision of several stimuli regardless of the participant’s strength level. This study aimed to compare the acute response in total repetitions as a measurement of performance, jump ability, physiological demand (heart rate and blood lactate), and perceived effort considering the participants’ strength level with individualized intensity in CrossFit. Thirty-five participants were assessed and asked to participate on two separate days in a standardized and relative ‘As Many Repetitions As Possible’ (AMRAP) CrossFit circuit. Both AMRAPs comprised strength, gymnastic and aerobic exercises, although only strength was individualized according to the participant’s level. Before the statistical analysis, participants were allocated to higher- or lower-strength groups following the one-repetition maximum-bodyweight ratio in the push press exercise. Results support the existence of a strong relationship between strength level and total repetitions in both AMRAPs. In addition, differences in total repetitions and rate of perceived exertion between strength groups are discarded when AMRAP intensity is individualized while physiological demand and jump ability are maintained. Thus, the higher-strength participants may benefit from similar responses with a lower number of repetitions. Therefore, CrossFit trainers should be encouraged to prescribe strength tasks based on the percentage of 1RM for every training.
... The shoulder press exercise, which lifts the barbell over the head during the resistance exercise, is widely used in the training, rehabilitation and sports field of athletes as a movement to train the muscle group around the shoulder. 1 Especially, the shoulder press in the standing posture has the operation of lifting the barbell over the head, and the lumbar extensor for stabilizing the trunk is active by using deltoid muscle and triceps brachii as the prime mover. 2 Also, shoulder press exercise using lower extremity and upper extremity at the same time is said to generate lower extremity force at a level similar to the operation using recoil like jump squat, and the operation of bending and unfolding the knee and hips provides efficient movement of lower extremity and upper extremity, 3 which is reported to occur as the segment of lower extremity unfolds. 4 The simultaneous force production of lower extremities in shoulder press motions can improve power, workload and potentially increase the activity of neuromusculars. ...
Background
In the realm of functional fitness training (FFT), three common circuits—as many repetitions or round as possible (AMRAP), for time (FT), and every minute on a minute (EMOM)—are prevalent. We aimed to elucidate the immediate impacts on athletes, considering the experience, when performing three workout modalities with matched training loads.
Methods
Twenty-five healthy men and women, with at least three months of experience in FFT, were allocated into the Inexperienced group (IG) and Experienced group (EG). The cut point for allocating participant in each group was set at 24 months. All of them participated in three workouts (AMRAP, FT and EMOM) with three days of rest. A double comparison was performed between level of experience (IG and EG) and among kinds of training in rating of perceived exertion (RPE), lactate concentration (LAC), countermovement jump (CMJ), heart rate (HR) and heart rate variability (HRV) using ANOVA and post-hoc Bonferroni tests.
Results
Sex was initially analyzed but had no influence, leading to combined group analyses. The workout type significantly impacted performance, with AMRAP showing differences between expertise levels (ES = 0.81, p = .044). RPE varied by workout type ( F (2,46) = 11.003; p < .001), with EG reporting FT as the most and EMOM as the least demanding. Lactate levels increased across all workouts, with FT showing the highest and EMOM the lowest levels ( ES = 1.05, p < .001). CMJ performance declined post-AMRAP and FT in both groups, but not after EMOM. No expertise-level differences were found in HRmean or HRmax, but HRV changes were influenced by workout type ( F (2,46) = 7.381; p < .01) and expertise ( F (1,23) = 4.657; p = .034), with significant decreases in HRV after AMRAP and FT for IG.
Conclusion
The study demonstrates that FT produced greater LAC and RPE as compared to an AMRAP, whereas EMOM generated less neuromuscular fatigue and Lac, particularly in EG. These results underscore the importance of individualizing workout selection to expertise level to optimize performance. Future research should explore longitudinal adaptation to different workout types across diverse populations.
The study aim was to compare kinetics and kinematics of two, lower-body free-weight exercises, calculated from concentric and propulsion sub-phases, across multiple loads. Sixteen strength trained men performed back squat one-repetition maximum tests (1RM) (visit 1), followed by two incremental back squat and jump squat protocols (visit 2) (loads = 0% and 30-60%, back squat 1RM). Concentric and propulsion phase force-time-displacement characteristics were derived from force-plate-data and compared via analysis of variance and Hedges g effect sizes. Intra-session reliability was calculated via intraclass correlation coefficient (ICC) and coefficient of variation (CV). All dependent variables met acceptable reliability (ICC > 0.7; CV < 10%). Statistically significant three-way interactions (load phase exercise) and two-way main effects (phase exercise) were observed for mean force, velocity (30-60% 1RM), power, work, displacement, and duration (0%, 30-50% 1RM) (p < 0.05). A significant two-way interaction (load exercise) was observed for impulse (p < 0.001). Jump squat velocity (g = 0.94-3.80), impulse (g = 1.98-3.21), power (g = 0.84-2.93) and work (g = 1.09-3.56) were significantly larger across concentric and propulsion phases, as well as mean propulsion force (g = 0.30-1.06) performed over all loads (p < 0.001). No statistically significant differences were observed for mean concentric force. Statistically longer durations (g = 0.38-1.54) and larger displacements (g = 2.03-4.40) were evident for all loads and both sub-phases (p < 0.05). Ballistic, lower-body exercise produces greater kinetic and kinematic outputs than non-ballistic equivalents, irrespective of phase determination. Practitioners should therefore utilize ballistic methods when prescribing or testing lower-body exercises to maximize athlete’s force-time-displacement characteristics.
The vertical ground reaction force (VGRF) and front foot sagittal plane movement of the weightlifting jerk were recorded from seven weightlifters. Average knee flexion during the dip phase was 58 ± 9 degrees (mean ± SD) at an average angular velocity of 125 ± 16 degrees.s-1 exerting a vertical impulse of 138 ± 17.3 Ns. The peak rate of force development was 17.2 ± 4.86 BW.s-1 , the VGRF continuing to increase from a propulsion impulse of 113.7 ± 31.2 Ns to a peak drive phase value of 3.5 ± 1.2 BW, extending the knees by 54 ± 9 degrees. The front foot catch phase peak impact VGRF was 3.4 ± 1.2 BW loading at a rate of 285 ±119 BW.s-1. The results indicate that although loading rates are not excessive during the catch phase, careful consideration should be given before introducing the jerk into the strength and conditioning program of the inexperienced.
There is a paucity of evidence-based support for the allocation of rest interval duration between incremental loads in the assessment of the load-power profile. We examined the effect of rest interval duration on muscular power production in the load-power profile, and sought to determine if greater rest is required with increasing load (i.e. variable rest interval). Ten physically trained males completed four experimental conditions in a cross-over, balanced design. Participants performed jump squats across incremental loads (0-60 kg) on four occasions, with an allocated recovery interval of 1, 2, 3, or 4 minutes. The mean log transformed power output at each load was used for comparison between conditions (rest intervals). Unloaded jump squats (0 kg) maximised power output at each condition. Pmax was 66.6 ± 6.5 W[BULLET OPERATOR]kg (1 min), 66.2 ± 5.2 W[BULLET OPERATOR]kg (2 min), 67.1 ± 5.9 W[BULLET OPERATOR]kg (3 min), and 66.2 ± 6.5 W[BULLET OPERATOR]kg (4 min). Trivial or unclear differences in power output were observed between rest intervals at each incremental load. As expected, power declined per 10kg increment in load, the magnitude of decrease was 13.9-14.5% (CL: ± 1.3-2.0%) and 13.4-14.6% (CL: ± 2.4-3.9%) for relative peak and mean power respectively, yet differences in power output between conditions were likely insubstantial. The prescription of rest intervals between loads that are longer than 1 min have a likely negligible effect on muscular power production in the jump squat incremental load-power profile. Practitioners should select either a 1-4 min rest interval to best accommodate the logistical constraints of their monitoring sessions.
This study examined the relative effectiveness of two leading forms of athletic training in enhancing dynamic performance in various tests. Thirty-three men who participated in various regional level sports, but who had not previously performed resistance training, were randomly assigned to either a maximal power training program, a combined weight and plyometric program, or a nontraining control group. The maximal power group performed weighted jump squats and bench press throws using a load that maximized the power output of the exercise. The combined group underwent traditional heavy weight training in the form of squats, and bench press and plyometric training in the form of depth jumps and medicine ball throws. The training consisted of 2 sessions a week for 8 weeks. Both training groups were equally effective in enhancing a variety of performance measures such as jumping, cycling, throwing, and lifting.
(C) 1996 National Strength and Conditioning Association
Films taken at the first Women’s World Weightlifting Championship were analyzed to determine the average power output during the total pulling phase, and the second pull phase, for the heaviest successful snatch and clean lift of gold medalists in each of nine body-weight divisions. Comparisons were made with previously published data on power output by male lifters in World and Olympic competition. Average relative power output values were one and a half to two times greater for both men and women when only the second pull phase of each lift was analyzed. Results show that women can generate higher short-term power outputs than previously documented, but lower than for men in absolute values and relative to body mass. Male/female comparisons in other high power sport events and basic strength measures are discussed. The high power outputs suggest the value of including the types of lifts analyzed in training programs to improve short-term power output.
Subjects performed maximum vertical jumps on a force platform to reveal whether resulting force-time curves could identify characteristics of good performances. Instantaneous power-time curves were also derived from the force-time curves. Eighteen temporal and kinetic variables were calculated from the force- and power-time curves and were compared with the takeoff velocities and maximum heights via correlation and multiple regression. The large variability in the patterns of force application between the subjects made it difficult to identify important characteristics of a good performance. Maximum positive power was found to be an excellent single predictor of height, but the best three-predictor model, not including maximum power, could only explain 66.2% of the height variance. A high maximum force (> 2 body weights) was found to be necessary but not sufficient for a good performance. Some subjects had low jumps in spite of generating high peak forces, which indicated that the pattern of force applica...
This study examined the relative effectiveness of two leading forms of athletic training in enhancing dynamic performance in various tests. Thirty-three men who participated in various regional level sports, but who had not previously performed resistance training, were randomly assigned to either a maximal power training program, a combined weight and plyometric program, or a nontraining control group. The maximal power group performed weighted jump squats and bench press throws using a load that maximized the power output of the exercise. The combined group underwent traditional heavy weight training in the form of squats, and bench press and plyometric training in the form of depth jumps and medicine ball throws. The training consisted of 2 sessions a week for 8 weeks. Both training groups were equally effective in enhancing a variety of performance measures such as jumping, cycling, throwing, and lifting.