scholarly journals Impact of Accommodating Resistance in Potentiating Horizontal-Jump Performance in Professional Rugby League Players

2018 ◽  
Vol 13 (9) ◽  
pp. 1223-1229
Author(s):  
Alasdair Strokosch ◽  
Loic Louit ◽  
Laurent Seitz ◽  
Richard Clarke ◽  
Jonathan D. Hughes
Keyword(s):  
Body Mass ◽  
Repeated Measures ◽  
Effective Means ◽  
Rugby League ◽  
Elastic Band ◽  
Training Experience ◽  
Jump Performance ◽  
Repetition Maximum ◽  
Repeated Measures Design ◽  
Back Squat

This study investigated the efficacy of deadlifts and box squats, with a combination of traditional and accommodating resistance, as a postactivation potentiating stimulus of standing broad jumps (SBJ) in a multiple-set contrast protocol. Twelve professional rugby league players (21.4 [2.5] y; 181.3 [8.3] cm, 91.9 [8.8] kg; 1-repetition-maximum [1RM] back squat/body mass 1.59 [0.21]; 1RM deadlift/body mass 2.11 [0.25]; ≥3-y resistance-training experience) performed baseline SBJ before a contrast postactivation potentiating protocol involving 2 repetitions of 85% 1RM box squat or deadlifts, loaded with a combination of traditional barbell weight (70% 1RM) and elastic-band resistance (∼15% 1RM), followed by 2 SBJs. Exercises were separated by 90 s, and 4 contrast pairs were performed in total. Using a repeated-measures design, all subjects performed the squat followed by the deadlift and finally the control (SBJ only) condition in the same order across consecutive weeks. Changes from baseline in SBJ distance were moderate for the box squat (effect size [ES] = 0.64–1.03) and deadlift (ES = 0.80–0.96) and trivial in the control condition (ES = 0.02–0.11). The magnitude of differences in postactivation potentiating effect were considered moderate (d = 0.61) for set 1, trivial for set 2 (d = 0.10) and set 3 (d = 0.05) in favor of box squats, and moderate for set 4 (d = 0.58) in favor of deadlifts. Accommodating resistance in either box squats or deadlifts is an effective means of potentiating SBJ performance across multiple sets of a contrast protocol with only 90-s rest.

scholarly journals Effects of Elastic Band Based Plyometric Exercise on Explosive Muscular Performance and Change of Direction Abilities of Male Team Handball Players

2020 ◽  
Vol 11 ◽  
Author(s):  
Ghaith Aloui ◽  
Souhail Hermassi ◽  
Mehrez Hammami ◽  
Yosser Cherni ◽  
Nawel Gaamouri ◽  
...  
Keyword(s):  
Body Mass ◽  
Body Fat ◽  
Muscle Power ◽  
Plyometric Training ◽  
Elastic Band ◽  
Anthropometric Parameters ◽  
Jump Performance ◽  
Change Of Direction ◽  
Team Handball ◽  
Back Squat

This study examined the effects of incorporating 8 weeks of bi-weekly lower limb elastic band based loaded plyometric training into the in-season regimen of junior handball players. Participants were assigned between control (n = 15, age: 18.1 ± 0.5 years, body mass: 73.7 ± 13.9 kg, height: 1.82 ± 0.06 m, body fat: 14.4 ± 6.0%) and experimental groups (n = 14, age: 17.7 ± 0.3 years, body mass: 76.8 ± 10.7 kg, height: 1.83 ± 0.04 m, body fat: 13.4 ± 3.8%). Measures obtained before and after the intervention included a cycle ergometer force-velocity test, squat and countermovement jump characteristics, sprints times, repeated change of direction and change of direction tests (COD), a 1-RM half-back squat, and anthropometric estimates of limb volumes. Gains in the experimental group relative to controls included absolute muscle power (W) (Δ 23.1%; p < 0.05; ES = 0.565), relative muscle power (W.kg–1) (Δ 22.1%; p < 0.05; ES = 0.573), sprint times over 5 and 30 m (Δ−8.7%; p < 0.01; ES = 0.921 and Δ−7.2%; p < 0.05; ES = 0.573, respectively), COD times (Δ−9.2%; p < 0.05; ES = 0.561) and all repeated COD parameters except the fatigue index. However, a significant improvement by time interaction was observed in both groups on some anthropometric parameters (leg muscle volume and surface section thigh max), 1-RM half- back squat and vertical jump performance. We conclude that bi-weekly elastic band-loaded plyometric training improves the ability to sprint, COD and repeated COD relative to regular training, and thus it can be recommended to young male team handball players as a new method of plyometric training to improve important elements of their physical performance.

scholarly journals Is there a relationship between the overhead press and split jerk maximum performance? Influence of sex

2021 ◽  
pp. 174795412110204
Author(s):  
Marcos A Soriano ◽  
G Gregory Haff ◽  
Paul Comfort ◽  
Francisco J Amaro-Gahete ◽  
Antonio Torres-González ◽  
...  
Keyword(s):  
Confidence Intervals ◽  
Body Mass ◽  
Upper Limb ◽  
High Reliability ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Training Experience ◽  
Maximum Performance ◽  
Repetition Maximum ◽  
Intraclass Correlation Coefficients

The aims of this study were to (I) determine the differences and relationship between the overhead press and split jerk performance in athletes involved in weightlifting training, and (II) explore the magnitude of these differences in one-repetition maximum (1RM) performances between sexes. Sixty-one men (age: 30.4 ± 6.7 years; height: 1.8 ± 0.5 m; body mass 82.5 ± 8.5 kg; weightlifting training experience: 3.7 ± 3.5 yrs) and 21 women (age: 29.5 ± 5.2 yrs; height: 1.7 ± 0.5 m; body mass: 62.6 ± 5.7 kg; weightlifting training experience: 3.0 ± 1.5 yrs) participated. The 1RM performance of the overhead press and split jerk were assessed for all participants, with the overhead press assessed on two occasions to determine between-session reliability. The intraclass correlation coefficients (ICC) and 95% confidence intervals showed a high reliability for the overhead press ICC = 0.98 (0.97 – 0.99). A very strong correlation and significant differences were found between the overhead press and split jerk 1RM performances for all participants (r = 0.90 [0.93 – 0.85], 60.2 ± 18.3 kg, 95.7 ± 29.3 kg, p ≤ 0.001). Men demonstrated stronger correlations between the overhead press and split jerk 1RM performances (r = 0.83 [0.73-0.90], p ≤ 0.001) compared with women (r = 0.56 [0.17-0.80], p = 0.008). These results provide evidence that 1RM performance of the overhead press and split jerk performance are highly related, highlighting the importance of upper-limb strength in the split jerk maximum performance.

scholarly journals Enhancement of Countermovement Jump Performance Using a Heavy Load with Velocity-Loss Repetition Control in Female Volleyball Players

2021 ◽  
Vol 18 (21) ◽  
pp. 11530
Author(s):  
Michal Krzysztofik ◽  
Rafal Kalinowski ◽  
Robert Trybulski ◽  
Aleksandra Filip-Stachnik ◽  
Petr Stastny
Keyword(s):  
Body Mass ◽  
Repeated Measures ◽  
Performance Enhancement ◽  
Countermovement Jump ◽  
Mean Power ◽  
Mean Velocity ◽  
Heavy Load ◽  
Jump Performance ◽  
Volleyball Players ◽  
Post Hoc

Although velocity control in resistance training is widely studied, its utilization in eliciting post-activation performance enhancement (PAPE) responses receives little attention. Therefore, this study aimed to evaluate the effectiveness of heavy-loaded barbell squats (BS) with velocity loss control conditioning activity (CA) on PAPE in subsequent countermovement jump (CMJ) performance. Sixteen resistance-trained female volleyball players participated in this study (age: 24 ± 5 yrs.; body mass: 63.5 ± 5.2 kg; height: 170 ± 6 cm; relative BS one-repetition maximum (1RM): 1.45 ± 0.19 kg/body mass). Each participant performed two different conditions: a set of the BS at 80% 1 RM with repetitions performed until a mean velocity loss of 10% as the CA or a control condition without CA (CNTRL). To assess changes in jump height (JH) and relative mean power output (MP), the CMJ was performed 5 min before and throughout the 10 min after the CA. The two-way analysis of variance with repeated measures showed a significant main effect of condition (p = 0.008; η2 = 0.387) and time (p < 0.0001; η2 = 0.257) for JH. The post hoc test showed a significant decrease in the 10th min in comparison to the value from baseline (p < 0.006) for the CNTRL condition. For the MP, a significant interaction (p = 0.045; η2 = 0.138) was found. The post hoc test showed a significant decrease in the 10th min in comparison to the values from baseline (p < 0.006) for the CNTRL condition. No significant differences were found between all of the time points and the baseline value for the CA condition. The CA used in the current study fails to enhance subsequent countermovement jump performance in female volleyball players. However, the individual analysis showed that 9 out of the 16 participants (56%) responded positively to the applied CA, suggesting that the PAPE effect may be individually dependent and should be carefully verified before implementation in a training program.

scholarly journals Effect of acute antagonist static stretching on upper-body agonist power

2019 ◽  
Vol 15 (1) ◽  
pp. 53-59
Author(s):  
Dave Elliott ◽  
Dayne Massey
Keyword(s):  
Repeated Measures ◽  
Effective Means ◽  
Upper Body ◽  
Static Stretching ◽  
Repeated Measures Design ◽  
Significant Difference ◽  
Potential Benefits ◽  
Upper Body Power ◽  
The Impact ◽  
Practical Implications

There are many studies showing acute static stretching to be detrimental to power generation. However, the majority have focused upon the impact of stretching the agonist musculature. To date, few have examined the potential benefits of acute antagonist static stretching; none have focused on upper-body power. Utilising a repeated-measures design, 30 male participants were randomly assigned to one of two groups whereupon they performed four bench-throw tests; two control (NO-STRETCH) and two experimental (STRETCH), in a counter-balanced manner. Prior to the experimental measures, participants undertook a series of static antagonist stretches. Mean Pmax (SD) in the NO-STRETCH trials was 862.76 (146)W and 898.50 (144)W, respectively. For STRETCH trial 1, Pmax = 930.10 (146)W and trial 2, Pmax = 953.36 (136)W. When compared to the respective NO-STRETCH trials, antagonist static stretching did have a significant effect on Pmax for both the initial ( P < 0.01, d = 1.33) and the re-stretching procedures ( P < 0.01, d = 1.35). A significant difference was also found between the STRETCH trials ( P < 0.01, d = 0.46). The results have practical implications for those involved in upper-body power activities. Specifically, incorporating upper-body antagonist static stretching into pre-performance routines might offer a simple and effective means of enhancing agonist power.

Improving Hearing Performance for Cochlear Implant Recipients with Use of a Digital, Wireless, Remote-Microphone, Audio-Streaming Accessory

2015 ◽  
Vol 26 (06) ◽  
pp. 532-539 ◽  
Author(s):  
Jace Wolfe ◽  
Mila Morais ◽  
Erin Schafer
Keyword(s):  
Speech Recognition ◽  
Cochlear Implant ◽  
Repeated Measures ◽  
Signal To Noise Ratio ◽  
Effective Means ◽  
Audio Signals ◽  
Noise Levels ◽  
Repeated Measures Design ◽  
Accessory Device ◽  
Sound Processor

Background: Cochlear implant (CI) recipients experience difficulty understanding speech in noise. Remote-microphone technology that improves the signal-to-noise ratio is recognized as an effective means to improve speech recognition in noise; however, there are no published studies evaluating the potential benefits of a wireless, remote-microphone, digital, audio-streaming accessory device (heretofore referred to as a remote-microphone accessory) designed to deliver audio signals directly to a CI sound processor. Purpose: The objective of this study was to compare speech recognition in quiet and in noise of recipients while using their CI alone and with a remote-microphone accessory. Research Design: A two-way repeated measures design was used to evaluate performance differences obtained in quiet and in increasing levels of competing noise with the CI sound processor alone and with the sound processor paired to the remote microphone accessory. Study Sample: Sixteen users of Cochlear Nucleus 24 Freedom, CI512, and CI422 implants were included in the study. Data Collection and Analysis: Participants were evaluated in 14 conditions including use of the sound processor alone and with the remote-microphone accessory in quiet and at the following signal levels: 65 dBA speech (at the location of the participant; 85 dBA at the location of the remote microphone) in quiet and competing noise at 50, 55, 60, 65, 70, and 75 dBA noise levels. Speech recognition was evaluated in each of these conditions with one full list of AzBio sentences. Results: Speech recognition in quiet and in all competing noise levels, except the 75 dBA condition, was significantly better with use of the remote-microphone accessory compared with participants’ performance with the CI sound processor alone. As expected, in all technology conditions, performance was significantly poorer as the competing noise level increased. Conclusions: Use of a remote-microphone accessory designed for a CI sound processor provides superior speech recognition in quiet and in noise when compared with performance obtained with the CI sound processor alone.

Jump Shrug Height and Landing Forces Across Various Loads

2016 ◽  
Vol 11 (1) ◽  
pp. 61-65 ◽  
Author(s):  
Timothy J. Suchomel ◽  
Christopher B. Taber ◽  
Glenn A. Wright
Keyword(s):  
Potential Energy ◽  
Body Mass ◽  
Repeated Measures ◽  
External Load ◽  
Track And Field ◽  
Pairwise Comparisons ◽  
Jump Height ◽  
Repetition Maximum ◽  
Power Clean

The purpose of this study was to examine the effect that load has on the mechanics of the jump shrug. Fifteen track and field and club/intramural athletes (age 21.7 ± 1.3 y, height 180.9 ± 6.6 cm, body mass 84.7 ± 13.2 kg, 1-repetition-maximum (1RM) hang power clean 109.1 ± 17.2 kg) performed repetitions of the jump shrug at 30%, 45%, 65%, and 80% of their 1RM hang power clean. Jump height, peak landing force, and potential energy of the system at jump-shrug apex were compared between loads using a series of 1-way repeated-measures ANOVAs. Statistical differences in jump height (P < .001), peak landing force (P = .012), and potential energy of the system (P < .001) existed; however, there were no statistically significant pairwise comparisons in peak landing force between loads (P > .05). The greatest magnitudes of jump height, peak landing force, and potential energy of the system at the apex of the jump shrug occurred at 30% 1RM hang power clean and decreased as the external load increased from 45% to 80% 1RM hang power clean. Relationships between peak landing force and potential energy of the system at jump-shrug apex indicate that the landing forces produced during the jump shrug may be due to the landing strategy used by the athletes, especially at lighter loads. Practitioners may prescribe heavier loads during the jump-shrug exercise without viewing landing force as a potential limitation.

scholarly journals Acute Effects Of Different Stretching Durations on Vertical Jump Performance in Rhythmic Gymnasts

2018 ◽  
Vol 3 (82) ◽  
Author(s):  
Nuriye Özengin ◽  
Necmiye Ün Yıldırım ◽  
Gül Baltacı ◽  
Nerijus Masiulis
Keyword(s):  
Repeated Measures ◽  
Vertical Jump ◽  
Effective Means ◽  
Anaerobic Power ◽  
Static Stretching ◽  
Jump Performance ◽  
Warm Up ◽  
Rhythmic Gymnastics ◽  
Rhythmic Gymnasts ◽  
Stretching Exercises

Research background. Stretching is believed to enhance performance, reduce injury, and be an effective means of developing flexibility and alleviating muscular soreness (Shellock, Prentice, 1985; Brandy et al., 1997). A review of the current literature shows that the results of many studies conflict with others; some report that static stretching diminishes vertical jum (VJ) performance (Cornwell et al., 2001; McNeal, Sands, 2003; Wallmann et al., 2005), whereas others report that static stretching has no effect at all on VJ (Church et al., 2001; Power et al., 2004; Unick et al., 2005). Research aim, was to examine the effects of different durations of stretching on performance and to find the stretching durations that affect the performance negatively or positively. Research methods. The subjects of the study were 27 rhythmic gymnasts with the mean age of 10.00 ± 1.2 years. The subjects as a whole group participated in two different stretching programs on nonconsecutive days to eliminate the effect of individual differences on the performance. On the first day, athletes were asked to warm up by 5 minute jogging after the pretest was administered. The posttest measured the vertical jump performance after athletes stayed inactive for 20 minutes. They rested for a day and on the third day, their performance was measured again. After the 5 minute warm-up period, 10 repetitions of 15 seconds static stretching exercises for hip flexor, hamstring and gastrocnemius muscle groups were followed by the posttest. Moreover, on the fifth day 30-second exercises were repeated five times on the same type of muscles. The participants in this investigation were tested in individual vertical jump performances following warm-up only, warm-up plus 15 seconds static stretching, and warm-up plus 30 seconds. Research results. Results of a one-way repeated-measures ANOVA indicated a nonsignificant difference for vertical jump performance (F = 2.052; p > 0.05). Discussion and conclusions. Stretching exercises are referred in rhythmic gymnastics more intensively than other sports. Relevant literature displays fewer stretching repetitions and durations. These durations and repetitions may not be realistic and practical for rhythmic gymnasts. Therefore, the durations and repetitions utilized in this study are considered more appropriate for rhythmic gymnastics trainings. Rhythmic gymnasts may make use of duration and repetitions determined in this study that will not affect their performance.Keywords: anaerobic power, gymnastics, exercise.

scholarly journals The Effects of the Movement Tempo on the One-Repetition Maximum Bench Press Results

2020 ◽  
Vol 72 (1) ◽  
pp. 151-159 ◽  
Author(s):  
Michal Wilk ◽  
Artur Golas ◽  
Piotr Zmijewski ◽  
Michal Krzysztofik ◽  
Aleksandra Filip ◽  
...  
Keyword(s):  
Resistance Training ◽  
Repeated Measures ◽  
Bench Press ◽  
Trial And Error ◽  
Training Experience ◽  
Test Procedures ◽  
Test Protocol ◽  
Repetition Maximum ◽  
One Year ◽  
The One

AbstractDifferent tempos of movement can be used during resistance training, but programming them is often a trial-and-error practice, as changing the speed at which the exercise is performed does not always correspond with the tempo at which the 1-repetition-maximum occurred. Therefore, the aim of this study was to determine the effect of different movement tempos during the bench press (BP) exercise on the one-repetition maximum (1RM) load. Ninety men (age = 25.8 ± 5.3 years, body mass = 80.2 ± 14.9 kg), with a minimum one year of resistance training experience took part in the study. Using a randomized crossover design, each participant completed the BP 1RM test with five different movement tempos: V/0/V/0, 2/0/V/0, 5/0/V/0, 8/0/V/0 and 10/0/V/0. Repeated measures ANOVA compared the differences between the 1RM at each tempo. The 1RM load was significantly greater during V/0/V/0 and 2/0/V/0 compared to 5/0/V/0, 8/0/V/0, and 10/0/V/0 (p < 0.01). Furthermore, the 1RM load was significantly greater during 5/0/V/0 compared to 8/0/V/0 and 10/0/V/0 (p < 0.01), but there were no differences between either V/0/V/0 and 2/0/V/0 (p = 0.92) or between 8/0/V/0 and 10/0/V/0 (p = 0.08). Therefore, different movement tempos used during training should be accompanied by their own tempo-specific 1RM testing, as slower eccentric phases significantly decrease maximal concentric performance. Furthermore, 1RM test procedures should include information about the movement tempo used during the test protocol. In addition, the standardization of the tempo should be taken into account in investigations that use the 1 RM test to assess the effects of any treatment on maximal muscle strength.

scholarly journals Returners Exhibit Greater Jumping Performance Improvements During a Peaking Phase Compared With New Players on a Volleyball Team

2018 ◽  
Vol 13 (6) ◽  
pp. 709-716 ◽  
Author(s):  
Caleb D. Bazyler ◽  
Satoshi Mizuguchi ◽  
Ashley A. Kavanaugh ◽  
John J. McMahon ◽  
Paul Comfort ◽  
...  
Keyword(s):  
Peak Power ◽  
Perceived Exertion ◽  
Vastus Lateralis ◽  
Rating Of Perceived Exertion ◽  
Training Experience ◽  
Cross Sectional ◽  
Repetition Maximum ◽  
Jumping Performance ◽  
Performance Improvements ◽  
Back Squat

Purpose: To determine if jumping-performance changes during a peaking phase differed among returners and new players on a female collegiate volleyball team and to determine which variables best explained the variation in performance changes. Methods: Fourteen volleyball players were divided into 2 groups—returners (n = 7) and new players (n = 7)—who completed a 5-wk peaking phase prior to conference championships. Players were tested at baseline before the preseason on measures of the vastus lateralis cross-sectional area using ultrasonography, estimated back-squat 1-repetition maximum, countermovement jump height (JH), and relative peak power on a force platform. Jumping performance, rating of perceived exertion training load, and sets played were recorded weekly during the peaking phase. Results: There were moderate to very large (P < .01, Glass Δ = 1.74) and trivial to very large (P = .07, Δ = 1.09) differences in JH and relative peak power changes in favor of returners over new players, respectively, during the peaking phase. Irrespective of group, 7 of 14 players achieved peak JH 2 wk after the initial overreach. The number of sets played (r = .78, P < .01) and the athlete’s preseason relative 1-repetition maximum (r = .54, P = .05) were the strongest correlates of JH changes during the peaking phase. Conclusions: Returners achieved greater improvements in jumping performance during the peaking phase compared with new players, which may be explained by the returners’ greater relative maximal strength, time spent competing, and training experience. Thus, volleyball and strength coaches should consider these factors when prescribing training during a peaking phase to ensure their players are prepared for important competitions.

Prohormone supplement 3β-hydroxy-5α-androst-1-en-17-one enhances resistance training gains but impairs user health

2014 ◽  
Vol 116 (5) ◽  
pp. 560-569 ◽  
Author(s):  
Jorge Granados ◽  
Trevor L. Gillum ◽  
Kevin M. Christmas ◽  
Matthew R. Kuennen
Keyword(s):  
Body Composition ◽  
Resistance Training ◽  
Lean Body Mass ◽  
Body Mass ◽  
Muscular Strength ◽  
Fat Body ◽  
Resistance Training Program ◽  
Repetition Maximum ◽  
Back Squat ◽  
Fat Body Mass

Prohormone supplements (PS) are recognized not to impart anabolic or ergogenic effects in men, but the research supporting these conclusions is dated. The Anabolic Steroid Control Act was amended in 2004 to classify androstenedione and 17 additional anabolic compounds as controlled substances. The viability of PS that entered the market after that time have not been evaluated. Seventeen resistance-trained men (23 ± 1 yr; 13.1 ± 1.5% body fat) were randomly assigned to receive either 330 mg/day of 3β-hydroxy-5α-androst-1-en-17-one (Prohormone; n = 9) or sugar (Placebo; n = 8) per os and complete a 4-wk (16 session) structured resistance-training program. Body composition, muscular strength, circulating lipids, and markers of liver and kidney dysfunction were assessed at study onset and termination. Prohormone increased lean body mass by 6.3 ± 1.2%, decreased fat body mass by 24.6 ± 7.1%, and increased their back squat one repetition maximum and competition total by 14.3 ± 1.5 and 12.8 ± 1.1%, respectively. These improvements exceeded ( P < 0.05) Placebo, which increased lean body mass by 0.5 ± 0.8%, reduced fat body mass by 9.5 ± 3.6%, and increased back squat one repetition maximum and competition total by 5.7 ± 1.7 and 5.9 ± 1.7%, respectively. Prohormone also experienced multiple adverse effects. These included a 38.7 ± 4.0% reduction in HDL ( P < 0.01), a 32.8 ± 15.05% elevation in LDL ( P < 0.01), and elevations of 120.0 ± 22.6 and 77.4 ± 12.0% in LDL-to-HDL and cholesterol-to-HDL ratios, respectively (both P < 0.01). Prohormone also exhibited elevations in serum creatinine (19.6 ± 4.3%; P < 0.01) and aspartate transaminase (113.8 ± 61.1%; P = 0.05), as well as reductions in serum albumin (5.1 ± 1.9%; P = 0.04), alkaline phosphatase (16.4 ± 4.7%; P = 0.04), and glomerular filtration rate (18.0 ± 3.3%; P = 0.04). None of these values changed (all P > 0.05) in Placebo. The oral PS 3β-hydroxy-5α-androst-1-en-17-one improves body composition and muscular strength. However, these changes come at a significant cost. Cardiovascular health and liver function are particularly compromised. Given these findings, we feel the harm associated with this particular PS outweighs any potential benefit.

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