Power Clean Research Articles

Relationship Between Body Composition And Sport-specific Performance Metrics In Ncaa Di Female Volleyball Players

PURPOSE: The present study examined the relationship between body composition and sport-specific performance markers in NCAA Division I female volleyball players. METHODS: Twelve NCAA DI female volleyball players were assessed for body composition [body mass (BM), fat mass (FM), fat-free mass (FFM), body fat % (BF%)] via air displacement plethysmography (BODPOD) and sport-specific performance metrics [standing vertical jump (SVJ), pull-ups (PU), power clean (PC), back squat (BS), bench press (BP), and 5-10-5 pro agility shuttle (PA)] pre-, mid-, and post-season. Pearson and partial correlations assessed the relationships between FM, FFM, and performance metrics. RESULTS: FM and FFM were highly correlated (r=0.521, p<0.01). FM and PC were correlated (r=0.405, p=0.01) when assessed via Pearson correlation but no longer correlated when controlling for FFM (partial correlation, r=0.084, p<0.05). FM and SVJ were correlated when controlling for FFM (r=-0.477, p<0.05). FFM was correlated (Pearson, p<0.05) with BP (r= 0.335), PC (r=0.748), SVJ (r=0.659), and PA (r=-0.373). When controlling for FM, partial correlations (p<0.03) existed between FFM and PC (r=0.653), SVJ (r=0.707), and PA (r=-0.407). CONCLUSION: SVJ was the only performance variable that correlated with FM when controlling for FFM. FFM was positively correlated with PC and SVJ, and negatively with PA when controlling for FM. This suggests greater amounts of FFM are more advantageous for performance in the PC (lift greater amounts of weight) and PA (perform in less time) than having low FM, while having low FM or greater FFM are both advantageous for SVJ (greater jump height).

Shoulder Injury - Soccer, Water Polo

HX: 3 Division I athletes at 1 university. Case 1- 21F soccer center midfielder presented with 1 month of insidious L shoulder pain that started posteriorly at the rhomboids and slowly migrated anteriorly. She denied any trauma. All activity worsened the pain, particularly shoulder ROM. She completed 6 weeks of rest and PT without improvement. Case 2- 19M water polo player presented with 2 months of R posterior shoulder pain without preceding trauma. He improved with 2 weeks of light activity and PT, but the pain worsened as he increased activity and acutely worsened after contact play. Case 3- 19M water polo player presented with 2 weeks of insidious onset L posterior shoulder pain. While executing power cleans, the pain became severe and he went to the ED. EXAM: Case 1-Diffuse pain limited L shoulder ROM. +mild GH internal rotation deficit. +tenderness and spasm of L trapezius, neck, levator, posterior deltoid, rhomboids. Spurling’s (-). RTC testing nl except for pain with supraspinatus testing. O’Brien’s (-). Case 2-Nl visual inspection. The R shoulder had full ROM with mild discomfort posteriorly with full abduction. R rhomboid major tender to palpation. RTC testing nl; O’Brien’s (-). Case 3-Nl inspection, ROM. L rhomboid major tender to palpation. RTC testing nl, biceps testing (-). DDX:1. Rhomboid strain 2. Myofascial pain 3. Suprascapular nerve impingement 4. Thoracic outlet syndrome TESTS/RESULTS: Case 1- L shoulder XR- nondisplaced stress fracture L 1st rib Bedside U/S- cortical irregularity of 1st rib CT chest w/o contrast- stress fracture L 1st rib Case 2- R shoulder XR,R ribs XR,MR RUE w/o contrast- nl Bedside U/S- cortical irregularity of R 1st rib Retrospective review of original XRs revealed subtle cortical irregularity of R 1st rib CT chest w/o contrast- nondisplaced stress fracture R 1st rib Case 3- CXR,L shoulder XR,CT chest w/o contrast- nondisplaced fracture L 1st rib Bedside U/S- L 1st rib fracture with large callus formation FINAL DX:1st rib stress fracture TX/OUTCOME: All cases with 1st rib stress fracture healed with standard relative rest, calcium and Vitamin D supplementation.

The Reliability and Validity of Current Technologies for Measuring Barbell Velocity in the Free-Weight Back Squat and Power Clean.

This study investigated the inter-day and intra-device reliability, and criterion validity of six devices for measuring barbell velocity in the free-weight back squat and power clean. In total, 10 competitive weightlifters completed an initial one repetition maximum (1RM) assessment followed by three load-velocity profiles (40–100% 1RM) in both exercises on four separate occasions. Mean and peak velocity was measured simultaneously on each device and compared to 3D motion capture for all repetitions. Reliability was assessed via coefficient of variation (CV) and typical error (TE). Least products regression (LPR) (R2) and limits of agreement (LOA) assessed the validity of the devices. The Gymaware was the most reliable for both exercises (CV < 10%; TE < 0.11 m·s−1, except 100% 1RM (mean velocity) and 90‒100% 1RM (peak velocity)), with MyLift and PUSH following a similar trend. Poorer reliability was observed for Beast Sensor and Bar Sensei (CV = 5.1–119.9%; TE = 0.08–0.48 m·s−1). The Gymaware was the most valid device, with small systematic bias and no proportional or fixed bias evident across both exercises (R2 > 0.42–0.99 LOA = −0.03–0.03 m·s−1). Comparable validity data was observed for MyLift in the back squat. Both PUSH devices produced some fixed and proportional bias, with Beast Sensor and Bar Sensei being the least valid devices across both exercises (R2 > 0.00–0.96, LOA = −0.36–0.46 m·s−1). Linear position transducers and smartphone applications could be used to obtain velocity-based data, with inertial measurement units demonstrating poorer reliability and validity.

Rate of Force Development Adaptations After Weightlifting-Style Training: The Influence of Power Clean Ability.

James, LP, Suchomel, TJ, Comfort, P, Haff, GG, and Connick, M. Rate of force development adaptations after weightlifting-style training: the influence of power clean ability. J Strength Cond Res 36(6): 1560-1567, 2022-This experiment examined changes to the rate of force development (RFD) expressed under loaded jump conditions between individuals with a higher (stronger) and lower (weaker) weightlifting performance (as assessed by the 1 repetition maximum [RM] power clean) after training with the weightlifting derivatives. Two groups of markedly different weightlifting ability undertook 10 weeks of training with the power clean variants, snatch pulls, and jump squats across heavy and light conditions. Testing was performed at baseline, after 5 weeks of training (mid-test) and after training (post-test). During testing, RFD was assessed under a series of loads (20-80% squat 1RM) through the jump squat. Furthermore, the force-velocity relationship, and unloaded jump strategy (through the force-time curve waveform), were also examined. Very large change (Hedge's g, 95% confidence interval [g] = 2.10, 1.24 to 4.16) in RFD at 20% 1RM at mid-test occurred within the stronger group. Conversely, a small increase (g = 0.27, 0.53-1.91) among the weaker subjects existed in this measure at mid-test, reaching a moderate increase at post-test (g = 0.71, -0.18 to 2.15). Limited improvements were seen by the stronger subjects in RFD at 60 and 80% 1RM at either mid-test (60%: g = 0.27, -0.75 to 1.33; 80% = 0.02, -1.01 to 1.00) or post-test (60%: g = 0.52, -0.38 to 1.80; 80% = -0.26, -1.23 to 0.77). The stronger group experienced a shift throughout the force-velocity relationship while a more force-dominant adaptation occurred in weaker subjects. Differences in jump strategy between groups were also noted. Such training will elicit practically different adaptations in rapid force production depending on the individual's baseline weightlifting ability.

Comparison of the Power Output Between the Hang Power Clean and Hang High Pull Across a Wide Range of Loads in Weightlifters.

Takei, S, Hirayama, K, and Okada, J. Comparison of the power output between the hang power clean and hang high pull across a wide range of loads in weightlifters. J Strength Cond Res 35(2S): S84-S88, 2021-The current study compared the peak power output during the hang power clean (HPC) and hang high pull (HHP) across a wide range of external loads in weightlifters. Eight weightlifters completed 1 repetition maximum (1RM) assessment for the HPC (1.59 ± 0.17 kg/body mass) and a power test for the HPC and HHP at relative loads of 40, 60, 70, 80, 90, 95, and 100% 1RM of the HPC. The ground reaction force and 2-dimensional bar position data were recorded to determine the system (barbell + body mass) kinetics and bar height, respectively. System power was calculated as force multiplied by system velocity. The HHP produced significantly greater peak power than the HPC at 40, 60, and 70% 1RM. Conversely, there was no statistical or practical difference in peak power between the exercises at 80, 90, 95, and 100% 1RM. No significant interaction was found in force at peak power, whereas velocity at peak power was significantly greater during the HHP than during the HPC at 40, 60, and 70% 1RM. In addition, significantly greater peak bar height was observed for the HHP than the HPC at 40, 60, and 70% 1RM. From the power output comparisons across loads, the HHP should be used over the HPC at loads of 40-70% 1RM, whereas the HPC and HHP can be interchangeably used at loads of 80-100% 1RM.

Influence of Power Clean Ability and Training Age on Adaptations to Weightlifting-Style Training.

James, LP, Comfort, P, Suchomel, TJ, Kelly, VG, Beckman, EM, and Haff, GG. Influence of power clean ability and training age on adaptations to weightlifting-style training. J Strength Cond Res 33(11): 2936-2944, 2019-The purpose of this investigation was to determine whether weightlifting actions are a viable method for improving athletic performance among weaker, inexperienced lifters when compared with individuals with a greater power clean (PC) result, and hence weightlifting ability and experience. Two groups of males with distinctly different PC performances (higher performance [HP]: N = 8; body mass [BM] = 78.1 ± 4.0 kg; 1 repetition maximum [1RM] PC = 1.08 ± 0.09 kg·BM; lower performance [LP]: N = 8; BM = 82.6 ± 14.0 kg; 1RM PC = 0.78 ± 0.1 kg·BM) and resistance training age (HP: resistance training experience = 3.5 ± 1.2 years; LP: resistance training experience = 1.44 ± 1.50 years) undertook 10 weeks of training involving weightlifting derivatives, in addition to supplemental ballistic and plyometric exercises. Testing of athletic performance (represented by measures derived from the countermovement jump) occurred at baseline, after 5 weeks of training, and after 10 weeks of training. Both groups significantly improved across the majority of outcome variables after training (Hedges' g = 0.98-2.55, p ≤ 0.01-0.05). Only the HP participants experienced significant changes at midtest (g = 0.99-1.27, p ≤ 0.01-0.05), whereas no significant changes were revealed between midtest and posttest in this group. In contrast to this, the LP participants displayed a significant improvement in relative impulse (g = 1.39, p < 0.01) and rate of force development (g = 1.91, p < 0.01) during this final period (p < 0.01). As weaker, inexperienced lifters underwent a significant and meaningful enhancement in maximal neuromuscular measures after weightlifting derivative-focused training, practitioners should consider early implementation of such exercises. However, it is important for coaches to note that a delayed training effect might be present in weaker, less experienced lifters.

Coaching the Power Clean: A Constraints-Led Approach

ABSTRACT Traditionally, strength and conditioning coaches have used explicit instructions when changing movement behavior. Recent work has questioned the efficacy of this approach. Whether explicit instruction is best for facilitating movement change is discussed along with an alternative approach. A brief review of traditional coaching methods is undertaken, highlighting differences between the traditional “coach-centered approach” and an “athlete-centered, constraints-led approach.” The constraints-led approach is applied to coaching the power clean. This provides an example of how strength and conditioning practitioners may approach the coaching of movement using methods that align with contemporary coaching as well as skill acquisition theory.

Is the Optimal Load for Maximal Power Output During Hang Power Cleans Submaximal?

The optimal load for maximal power output during hang power cleans (HPCs) from a mechanical perspective is the 1-repetition-maximum (1RM) load; however, previous research has reported otherwise. The present study thus aimed to investigate the underlying factors that determine optimal load during HPCs. Eight competitive Olympic weight lifters performed HPCs at 40%, 60%, 70%, 80%, 90%, 95%, and 100% of their 1RM while the ground-reaction force and bar/body kinematics were simultaneously recorded. The success criterion during HPC was set above parallel squat at the receiving position. Both peak power and relative peak power were maximized at 80% 1RM (3975.7 [439.1]W, 50.4 [6.6]W/kg, respectively). Peak force, force at peak power, and relative values tended to increase with heavier loads (P < .001), while peak system velocity and system velocity at peak power decreased significantly above 80% 1RM (P = .005 and .011, respectively). There were also significant decreases in peak bar velocity (P < .001) and bar displacement (P < .001) toward heavier loads. There was a strong positive correlation between peak bar velocity and bar displacement in 7 of 8 subjects (r > .90, P < .01). The knee joint angle at the receiving position fell below the quarter-squat position above 70% 1RM. Submaximal loads were indeed optimal for maximal power output for HPC when the success criterion was set above the parallel-squat position. However, when the success criterion was defined as the quarter-squat position, the optimal load became the 1RM load.

Characteristics of the Shrug Motion and Trapezius Muscle Activity During the Power Clean.

Nagao, H and Ishii, Y. Characteristics of the shrug motion and trapezius muscle activity during the power clean. J Strength Cond Res 35(12): 3288-3295, 2021-Although the shrug motion and trapezius muscle activity are commonly considered as important in Olympic weightlifting exercises, there are no data on the shrug motion in Olympic weightlifting. Providing objective data on shrug motion and upper trapezius muscle (TZ) activity during power clean (PC) will help coaches properly evaluate technique and select accessory exercises. The purpose of this study was to clarify the role of the shrug motion and TZ activity during PC. Twenty trained men performed the PC at 50, 70, and 90% of 1 repetition maximum (1RM). Kinematics motion data and TZ surface electromyography were recorded. The range of motion of the shrug angle (sROM) and scapular adduction angle (aROM) were calculated during each phase of the PC. The TZ activity of each phase was evaluated by the root-mean-square of TZ activity (TZ%RMS), normalized by the maximal voluntary contraction. In the first pull and transition phases, TZ%RMS was significantly larger (p < 0.05; η2 = 0.10, 0.11) at 90% 1RM than at 50% 1RM. In the second pull phase, the sROM and aROM were significantly larger (p < 0.01; η2 = 0.19, 0.19) at 50% 1RM than at 90% 1RM, and the TZ%RMS was significantly larger (p < 0.01; η2 = 0.30) at 50% 1RM than at 70% 1RM and 90% 1RM, and at 70% 1RM than at 90% 1RM. Trapezius muscle activity appears to work to maintain scapular position, especially in the first pull and transition phases. In the second pull phase, the TZ was aggressively contracted to elevate the scapula and pull the barbell, but the sROM decreased as the load increased.

Ground Reaction Force Characteristics In Power Cleans With And Without The Double Knee Bend Technique

INTRODUCTION: Muscular power (i.e. muscular force x shortening velocity) is arguably the most important physical quality an athlete can possess. Many athletes use power cleans to improve muscular power but are not taught to use a double knee bend (DKB). The DKB is used by competitive weightlifters to increase muscular power produced in the second pull of the power clean exercise. Thus, athletes using power cleans to improve muscular power without using the DKB may not experience optimal benefit from the exercise. PURPOSE: To determine differences in ground reaction force characteristics between a power clean from the floor both with, and without, the use of a DKB in athletes with weightlifting experience. METHODS: Six participants with weightlifting experience each performed three power cleans with and without a DKB at 80% of their self-reported one-repetition maximum. Ground reaction forces (GRFs) were captured using two force platforms (1200Hz). Commercially available biomechanical analysis software was used to calculate concentric impulse (IMPCON), peak vertical ground reaction force (VGRFPEAK), and rate of force development (RFD) in the second pull for each trial. Paired samples t-tests were used to compare dependent variables in each condition: DKB and NO DKB. Cohen’s d estimates of effects size were used to determine meaningful differences. RESULTS: RFD was greater in the second pull of the power clean when a DKB was used (p <.001, d = 2.25; DKB: 6922±1664; NO DKB: 4710±277 N/s). IMPCON was lower in the DKB condition (p <.001, d = 1.09; DKB: 146±28.8 N•s; NO DKB: 174±36.6 N•s), and no differences were observed in VGRFPEAK (p = 0.375, d = 0.15; DKB: 1607±221 N; NO DKB: 1582±169 N). CONCLUSIONS: Although no differences were observed in VGRFPEAK and IMPCON was reduced, RFD was significantly greater in the second pull with the DKB. These data suggest that DKB may enhance the training stimulus by enabling the athlete to produce comparable peak forces in shorter time periods by increasing muscular shortening velocity. This may be due to a positional optimization of muscular length-tension properties in the hip, knee, and ankle extensor musculature uniquely offered by utilizing a DKB technique.

Optimal Load Based on Body Mass: A Pilot Study with The Hang Power Clean

A key factor for success in sports is the athletes’ capacity of producing mechanical power output. Implementation of weightlifting derivatives such as the hang power clean (HPC) in training programs have been utilized and substantial increases in muscle power are reached when the athletes train at the load in which they produce the peak power output, also defined as the optimal load. The optimal load is commonly determined as a relative percentage of the maximum weight one can lift a single time during a specific exercise, defined as the 1-repetition maximum (1RM) for that exercise. Given the disadvantages of 1RM tests utilization such as risk of injuries and excessive amount of time required for those assessments, it has become apparent the need for alternative strategies for the optimal load identification. PURPOSE: To estimate the optimal load of the HPC from body mass (BM) percentages. METHODS: Nine healthy young men (age: 21.3 ± 1.8, height: 174.6 ± 6.8 cm, weight: 80.6 ± 6.2 kg, 1RM HPC: 90.8 ± 9.6 kg, 1RM to weight ratio: 1.13 ± 0.07) participated in this study. Subjects performed a 1RM in the HPC in the first session and during the second session the peak power was calculated across loads of 30, 40, 50, 60, 70, 80, and 90% of their BM in the HPC in a randomized order. RESULTS: Our results showed significant differences among the power output and the percentages of the BM. Briefly, power output at 30% of the BM was similar in relation to 40% and 50% of the BM, whilst significantly lower than 60%, 70%, 80% and 90% of the BM. For 40% of the BM, it was observed similar result in relation to 50% of the BM, whilst results significantly lower than 60%, 70%, 80% and 90% of the BM. For 50% of the BM, similar result it was observed only 60% of the BM, while lower power output it was observed in comparison to 70%, 80% and 90% of the BM. For 60% of the BM, lower power output was observed when compared to 70%, 80% and 90% of the BM. Finally, no significant differences were observed between 70% and 80% and 90% of the BM, as well as 80% and 90% of the BM. CONCLUSION: Our results indicate that the optimal load based on BM for HPC exercise occurs at 70%, 80% and 90% of the BM.

Improvement of Kinetic, Kinematic, and Qualitative Performance Variables of the Power Clean With the Hook Grip.

The power clean and other weightlifting movements are commonly used in the development of muscle power. However, there is a paucity of research examining the use of the hook grip (HG) in weightlifting performance. Therefore, the purpose of this study was to compare 1-repetition maximum (1RM) and kinetic, kinematic, and qualitative variables across a range of loads (75-100%) during power-clean performance with an HG and a closed grip. A total of 11 well-trained men (power-clean 1RM = 113.4 [15.9]kg, 1.34 × body mass) with at least 3 mo of HG experience volunteered to participate. Following a familiarization session, 1RM testing with the HG and closed grip were completed 5-7 d apart in a randomized order. Barbell kinetic and kinematic variables were recorded via a force platform and dual linear position transducer system. All subjects had a greater 1RM with the HG than with the closed grip (P < .001, effect size [ES] = 0.43). Peak velocity (ES = 0.41-0.70), peak power (ES = 0.43-0.61), peak force (ES = 0.50-0.57), and catch height (ES = 0.40-0.96) were significantly greater (P < .05) when using the HG at all or most of the submaximal intensities. In addition, subjects reported significantly greater perceptions of grip security, power, and technical competency at submaximal but not maximal loads. Athletes and coaches who implement weightlifting movements in their physical preparation should adopt the HG where possible. Furthermore, researchers and sport scientists should control and report the grip type used when performing weightlifting-type movements.

48-hour recovery of biochemical parameters and physical performance after two modalities of CrossFit workouts.

CrossFit is high-intensity interval training involving routines called ‘workouts of the day’ (WOD). The aim of the present study is to analyse biochemical parameters and physical performance after two modalities of CrossFit WODs, and to evaluate 48-hour recovery. Twelve trained CrossFit practitioners (age: 30.4 ± 5.37 years; VO2max: 47.8 ± 3.63 ml/min/kg; 1RM Power Clean: 93.2 ± 7.62 kg) participated in the study. A crossover design was applied, and participants completed two modalities of WODs on separate days: WOD1 (as many rounds as possible) and WOD2 (rounds for time). Blood lactate, ratings of perceived exertion and heart rate were measured to determine the intensity of training sessions. Biochemical parameters and physical performance were evaluated before, immediately after, 24 hours after and 48 hours after exercise. There were significant differences in intensity between WOD1 and WOD2 (lactate: 13.3±1.87 vs. 18.38±2.02 mmol/L, heart rate mean: 127.6±11.1 vs. 159.8±12.1 bpm), and blood glucose concentrations were significantly higher after WOD2 (135.4 ± 19.6 vs. 167.4±19.6 mg/dL). After exercise, WOD1 and WOD2 caused significant increases of hepatic transaminases, creatine phosphokinase and blood glucose, as well as a large decrease in the physical performance evaluated by the plank test. All these values returned to baseline by 48 hours after exercise. Both WODs caused metabolic and muscular stress, as well as a decrease in physical performance. All the levels recovered at 48 hours, so the stress caused by CrossFit WODs did not induce a pathological state.

Between-Session Reliability of Isometric Midthigh Pull Kinetics and Maximal Power Clean Performance in Male Youth Soccer Players.

Dos'Santos, T, Thomas, C, Comfort, P, McMahon, JJ, Jones, PA, Oakley, NP, and Young, AL. Between-session reliability of isometric midthigh pull kinetics and maximal power clean performance in male youth soccer players. J Strength Cond Res 32(12): 3373-3381, 2018-The aim of the study was to determine the between-session reliability of isometric midthigh pull (IMTP) kinetics and maximal weight lifted during the power clean (PC) in male youth soccer players, and to identify the smallest detectable differences between sessions. Thirteen male youth soccer players (age: 16.7 ± 0.5 years, height: 1.80 ± 0.08 m, and mass: 70.5 ± 9.4 kg) performed 3 IMTP trials, whereas only 10 soccer players performed maximal PCs. These were performed twice, separated by 48 hours to examine the between-session reliability. Intraclass correlation coefficients (ICCs) and coefficient of variation (CV) demonstrated high levels of within-session (ICC = 0.84-0.98, CV = 4.05-10.00%) and between-session reliability (ICC = 0.86-0.96, CV = 3.76-7.87%) for IMTP kinetics (peak force [PF] and time-specific force values 30-250 ms) and maximal PC (ICC = 0.96, CV = 3.23%), all meeting minimum acceptable reliability criteria. No significant differences (p > 0.05, effect size ≤0.22) were revealed between sessions for IMTP kinetics and maximal PC performance. Strength and conditioning coaches and practitioners should consider changes of >6.04% in maximal PC and changes in IMTP kinetics of >14.31% in force at 30 ms, >14.73% in force at 50 ms, >12.36% in force at 90 ms, >12.37% in force at 100 ms, >14.51% in force at 150 ms, >11.71% in force at 200 ms, >7.23% in force at 250 ms, and >8.50% in absolute PF as meaningful improvements in male youth soccer players. Decrements in the IMTP kinetics greater than the aforementioned values could possibly be used as an indicator of neuromuscular fatigue and preparedness for training or competition.

The effects of individualized resistance training volumeby heart rate variability in collegiate football players

Objectives: We sought to determine if individualized programming by heart rate variability (HRV), improves resistance training outcomes in American football players. Design and Methods: Twenty-seven National Collegiate Athletic Association (NCCA) Division II American football players (age 19.03 ± .98 y, height 185.50 ± 5.30 cm, body mass 100.59 ± 18.57 kg) were divided into an experimental (HVG) group (n = 11), and a control (CON, n = 16). Subjects completed 5-weeks of 3 d·wk ‒1 periodized resistance training during the offseason. The HVG monitored HRV on mornings before training, and their training volume was adjusted by their HRV. Specifically, on training days when HRV indicated that a subject was fatigued, the subject performed half of the originally planned repetitions for the training day. CON performed assigned workouts with no alterations. Performance was assessed via 1RM bench press (BP), power clean (PC), back squat (BS), and vertical jump (VJ) between groups using a 2 × 2 repeated measures analysis of variance (ANOVA). Results: The HVG had an average of 4 ± 1.51 days modified over the 5 wks, but volume load lifted was similar (p = 0.955) between groups. Repeated measures ANOVA revealed significant increases in BP (time effect p < .001), BS (time effect p < 0.001), PC (time effect p = 0.002), and VJ (time effect p = 0.042) for both HVG and CON. There were no significant betweengroup differences in performance variables. The group × time interaction for PC (p = 0.087) trended towards a significantly greater increase in HVG (+ 8.6%) vs. CON (+ 2.6%). Conclusions: Periodized training can improve performance without monitoring HRV, but it may have an advantageous effect for highly technical movements such as the PC.

Normalization For Body Mass Affects The Correlation of Strength Tests To Speed And Agility Tests

Previous research has explored the correlation between strength tests and speed-agility tests among athletes with varying results. Much of this can be attributed to differences in reported results based on absolute strength test values versus those normalized to body mass (BM). PURPOSE: This study was to compare the correlation between absolute strength, speed, and agility test results to those normalized using body mass. METHODS: Varsity Division I male football players (n = 327) were tested during several seasons. Tests for strength included one repetition maximum (1RM) back squat (BS), power clean (PC), and push jerk (PJ). Results were recorded as absolute values as well as normalized values, calculated by dividing each 1RM by the athlete’s BM. Tests for speed and agility included 40-yard dash (40YD), 10-yard dash (10YD), 20-yard shuttle run (SR) and standing vertical jump (VJ). A Pearson Product-Moment Correlation analysis was used to determine significant correlations between tests. RESULTS: Results are presented below, with the first table displaying the absolute values of the strength tests and the second table showing the normalized values:Table: No title available.*P≤0.05 CONCLUSIONS: The results suggest that the correlations between 1RM strength test, and speed-agility test results are affected by normalizing to BM. There is a stronger significant correlation between tests when 1RM strength test values are normalized to BM.

Distribution of lower extremity work during clean variations performed with different effort

ABSTRACTThe purpose of this research was to investigate how lower extremity work was distributed during the pull of cleans performed lifting the barbell to the minimum height required to receive it in a full squat (minimal height clean); or with maximum effort to elevate the barbell as high as possible and receiving it in either a full (maximal effort clean) or partial (power clean) squat. Eight weightlifters screened for proficient technique performed these clean variations at 80% of one repetition maximum. Work performed on the barbell and by the lower extremity net joint moments (NJM) was computed from marker trajectories and ground reaction forces. Total barbell work, lower extremity NJM work, knee extensor work, and knee joint excursion during the second pull was lower in the minimal height clean than the maximal effort and power cleans (P < 0.05). This research demonstrates that more knee extensor work is performed in the second pull of maximal effort and power cleans compared to the minimal height clean. The larger knee extensor work performed is due to larger knee joint excursion during the second pull of the maximal effort and power cleans, but not larger knee extensor NJM.

Relationships between Isometric Force-Time Characteristics and Dynamic Performance.

The purpose of this study was to explore the relationships between isometric mid-thigh pull (IMTP) force-time characteristics (peak force and time-specific force vales (100–250 ms)) and dynamic performance and compare dynamic performance between stronger and weaker athletes. Forty-three athletes from different sports (rowing, soccer, bicycle motocross, and hockey) performed three trials of the squat jump (SJ), countermovement jump (CMJ), and IMTP, and performed a one repetition maximum power clean (PC). Reactive strength index modified (RSImod) was also calculated from the CMJ. Statistically significant large correlations between IMTP force-time characteristics and PC (ρ = 0.569–0.674, p < 0.001), and moderate correlations between IMTP force-time characteristics (excluding force at 100 ms) and RSImod (ρ = 0.389–0.449, p = 0.013–0.050) were observed. Only force at 250 ms demonstrated a statistically significant moderate correlation with CMJ height (ρ = 0.346, p = 0.016) and no statistically significant associations were observed between IMTP force-time characteristics and SJ height. Stronger athletes (top 10) demonstrated statistically significantly greater CMJ heights, RSImods, and PCs (p ≤ 0.004, g = 1.32–1.89) compared to weaker (bottom 10) athletes, but no differences in SJ height were observed (p = 0.871, g = 0.06). These findings highlight that the ability to apply rapidly high levels of force in short time intervals is integral for PC, CMJ height, and reactive strength.

Study of Explosive Power as Performance Enhancing Factor Among Kabaddi Players

The study of power as a performance-enhancing factor among Kabaddi players is essential to comprehend the relationship between power development and athletic performance in this dynamic sport. Power plays a crucial role in Kabaddi, as it influences the ability to generate force rapidly, efficiently, and explosively, enabling athletes to execute actions such as sprinting, jumping, and tackling opponents effectively. This abstract provides an overview of the methodologies used to investigate power in Kabaddi performance. Performance tests, including vertical jump tests, standing broad jump tests, and agility tests, assess power-related abilities. Strength training interventions, targeting power development, involve exercises such as squats, lunges, power cleans, and plyometrics. Biomechanical analysis using motion capture systems and force plates evaluates the mechanics of Kabaddi movements. Comparative studies compare power-related characteristics and performance outcomes between elite and non-elite players. Longitudinal studies track the progress of players over time, measuring changes in strength, speed, agility, and on-field performance. These research approaches aim to enhance our understanding of power's impact on Kabaddi performance, provide evidence-based recommendations for training, and contribute to the development of Kabaddi players.

The Hang Power Clean

The Hang Power Clean