International Journal of Strength and Conditioning最新文献_第3页

External and Internal Loads in Sports Science: Time to Rethink? 运动科学中的外部和内部负荷:是时候重新思考了?

International Journal of Strength and Conditioning Pub Date : 2023-10-20 DOI: 10.47206/ijsc.v3i1.234

Bernardo Ide, Amanda Silvatti, Craig Staunton, Moacir Marocolo, Dustin Oranchuk, Gustavo Mota

引用次数: 0

Analysis of Power Output During the Countermovement and Split-Squat Jump Across Loads and High-Volume Repetitions in Elite Athletes 优秀运动员跨负荷、大容量重复反动作和分蹲跳的力量输出分析

International Journal of Strength and Conditioning Pub Date : 2023-10-13 DOI: 10.47206/ijsc.v3i1.247

Kevin McCurdy, None John Walker, None William Blaser

{"title":"Analysis of Power Output During the Countermovement and Split-Squat Jump Across Loads and High-Volume Repetitions in Elite Athletes","authors":"Kevin McCurdy, None John Walker, None William Blaser","doi":"10.47206/ijsc.v3i1.247","DOIUrl":"https://doi.org/10.47206/ijsc.v3i1.247","url":null,"abstract":"The primary purpose of this study was to determine the rate of peak power (PP) loss during the countermovement jump (CMJ) and split-squat jump (SSJ) across various loads within a set of high repetitions. Eleven collegiate track and field athletes who had several years of resistance training experience and were trained in the two types of jumps completed the study. The participants completed a familiarization session and 2 data collection sessions. The CMJ and SSJ were completed in random order during session 1 and 2 separated by a minimum of 72 hours. Three loads using dumbbells took place in random order with each session including body weight only (BW0), body weight plus 15% (BW15) and body weight plus 30% BW(30) for the SSJ and BW(0), BW(25), and BW(50) for the CMJ. PP was determined using the PUSH 2.0 3D accelerometer worn at the waist, which was connected to an ipad app using Bluetooth. The participants completed 14 repetitions each set with 8 min rest between sets. Repetition 3 demonstrated the highest mean PP (PPmax) within the set. No significant decrease in PP was observed until repetition 6 (3.6% below PPmax) during the SSJ and repetition 8 (5.2% below PPmax) during the CMJ. These data indicate that 5 or less repetitions should be completed during the CMJ and 7 or less for the SSJ when training for PP. Using 10% reduction in PP as an effective level to train for power endurance, we recommend completing a minimum of 12 repetitions during the CMJ and a minimum of 10 repetitions for the SSJ.","PeriodicalId":170948,"journal":{"name":"International Journal of Strength and Conditioning","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135918723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Where is the Sport Science in American Football? 美式足球的运动科学在哪里?

International Journal of Strength and Conditioning Pub Date : 2023-10-06 DOI: 10.47206/ijsc.v3i1.230

Benjamin Gleason, Patrick Ward, William Hornsby

引用次数: 0

Post-Activation Performance Enhancement (PAPE) After Resisted Sprinting in Recreationally Active Participants: A Double-Blind Randomised Crossover Trial 娱乐活动参与者抵抗冲刺后激活后表现增强(PAPE):一项双盲随机交叉试验

International Journal of Strength and Conditioning Pub Date : 2023-09-29 DOI: 10.47206/ijsc.v3i1.226

Mark Godwin, Sahil Dhone, Mark Newman

{"title":"Post-Activation Performance Enhancement (PAPE) After Resisted Sprinting in Recreationally Active Participants: A Double-Blind Randomised Crossover Trial","authors":"Mark Godwin, Sahil Dhone, Mark Newman","doi":"10.47206/ijsc.v3i1.226","DOIUrl":"https://doi.org/10.47206/ijsc.v3i1.226","url":null,"abstract":"Sprint performance and therefore sprint training play important roles in a range of sports and numerous methods to enhance sprint performance have been proposed. One such method is resisted sprinting, whereby a predetermined load (% body mass) or a load which elicits a reduction in sprint velocity, is towed over a prescribed distance. Resisted sprint training can be implemented chronically or acutely. The latter is used to elicit a performance enhancement via post-activation potentiation whereby a superior performance may be achieved when the activity is preceded by a specific stimulus, usually as part of the warm up. The purpose of this study was to determine if a post-activation performance enhancement (PAPE) could be achieved following an acute resisted sprint at two different decreases in sprint velocity using novel resisted sprint equipment (Run Rocket). Eleven healthy male, recreationally trained volunteers (age 23.4 ± 1.9 years, height 180.5 ± 3.5 cm, body mass 86.4 ± 14.5 kg) participated in the study. A maximal 15 m baseline body mass only sprint was performed on the initial visit to ascertain 5 and 15 m sprint time. Participants visited a further two times which consisted of a pre-conditioning resisted sprint activity using the Run Rocket at two different resistance settings in a randomised counter-balanced design. A repeated measures analysis of variance (rmANOVA) showed no significant differences in sprint time, velocity or acceleration between the three conditions (p> 0.05). However, when assessing individuals by the smallest worthwhile change, some participants may have decreased their sprint time. Therefore, the use of resisted sprints did not elicit a post-activation performance enhancement in recreationally trained individuals and may not be beneficial for augmenting acute performance in this population. Individual responses to this type of training may vary and should be a consideration for strength coaches.","PeriodicalId":170948,"journal":{"name":"International Journal of Strength and Conditioning","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135246664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Effects of Accentuated Eccentric Loading on Barbell and Trap Bar Countermovement Jumps 加重偏心载荷对杠铃和单杠反动作跳跃的影响

International Journal of Strength and Conditioning Pub Date : 2023-09-22 DOI: 10.47206/ijsc.v3i1.213

Christopher Taber, Calin Butler, Victoria Dabek, Benjamin Kochan, Kyle McCormick, Emily Petro, Timothy Suchomel, Justin Merrigan

{"title":"The Effects of Accentuated Eccentric Loading on Barbell and Trap Bar Countermovement Jumps","authors":"Christopher Taber, Calin Butler, Victoria Dabek, Benjamin Kochan, Kyle McCormick, Emily Petro, Timothy Suchomel, Justin Merrigan","doi":"10.47206/ijsc.v3i1.213","DOIUrl":"https://doi.org/10.47206/ijsc.v3i1.213","url":null,"abstract":"This study examined effects of accentuated eccentric loading (AEL) on barbell and trap bar loaded countermovement jumps (LCMJ). Twenty-one subjects (16 male, 5 female; Age: 23.5 ± 1.8 years; Body mass: 81.4 ± 10.6 kg; Height: 176.9 ± 7.2 cm; Training age: 7.1 ± 2.6 years) participated in this study. Upon establishing one repetition maximum and baseline jumping conditions, three experimental loading sessions were completed in random order. Barbell and trap bar LCMJ were performed with a spectrum of fixed loads from 20-50 kg during control conditions and with additional AEL loads of 10, 20, or 30 kg for experimental conditions. According to coefficients of variation (<10%), jump height, modified reactive strength index (mRSI), force, impulse, and duration measures were considered reliable across conditions. Mixed effect models analyzed effects of AEL against fixed loading in trap bar and barbell LCMJ (p < 0.05). Compared to the control condition, AEL produced negligible reductions in jump height during barbell LCMJ and small reductions during trap bar LCMJ. Modified reactive strength indexes were reduced by AEL during barbell LCMJ but not trap bar LCMJ. Average braking forces were greater in AEL conditions, while propulsive impulse was lower in the AEL conditions. The barbell LCMJ with AEL resulted in longer propulsive durations and unchanged braking durations, while propulsive and braking durations were lower during trap bar LCMJ with AEL compared to control conditions. This investigation revealed that use of AEL increases eccentric braking forces but decreases propulsive phase outputs, which subsequently may result in negligible to small acute decreases in LCMJ height. Implementing AEL during LCMJ may be an effective strategy to improve deceleration / eccentric abilities. Future research should explore longitudinal power and deceleration adaptations, while concomitantly improving acutely altered movement mechanics from AEL.","PeriodicalId":170948,"journal":{"name":"International Journal of Strength and Conditioning","volume":"92 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136062085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effects of Band-Resisted Abduction on Muscle Activity between the Barbell Hip Thrust and Barbell Glute Bridge 带抗外展对杠铃臀部推力和杠铃臀桥之间肌肉活动的影响

International Journal of Strength and Conditioning Pub Date : 2023-09-15 DOI: 10.47206/ijsc.v3i1.223

Derek Kennedy, Jeffrey B. Casebolt, Gene L. Farren, Michelle Bartlett

{"title":"Effects of Band-Resisted Abduction on Muscle Activity between the Barbell Hip Thrust and Barbell Glute Bridge","authors":"Derek Kennedy, Jeffrey B. Casebolt, Gene L. Farren, Michelle Bartlett","doi":"10.47206/ijsc.v3i1.223","DOIUrl":"https://doi.org/10.47206/ijsc.v3i1.223","url":null,"abstract":"The importance of hip extensor and abductor muscles for sport performance and injury reduction is well-documented. To target these muscle groups, the barbell hip thrust and barbell glute bridge are used to load the posterior kinetic chain while band-resisted abduction exercises, like band-resisted side stepping, target the lateral kinetic chain. However, combining band-resisted hip abduction with barbell hip-extension dominant exercises has not yet been investigated. In this study, ten male subjects underwent a two-part research protocol with surface electromyography (sEMG) measured during a 5-repetition maximum (5-RM) load performance to determine differences in peak and mean muscular activity between band-resisted barbell hip thrust (BBHT) and barbell hip thrust (BHT), and between band-resisted barbell glute bridge (BBGB) and barbell glute bridge (BGB). The results indicated three significant differences between the pairs, with both banded conditions eliciting greater sEMG activity in the Upper Gluteus Maximus compared to non-banded conditions. However, BGB unexpectedly elicited greater sEMG activity in the Gluteus Medius compared to BBGB. The differences in muscle activity could potentially be explained by reciprocal inhibition and synergistic dominance. Further research is needed to make definitive statements on the superiority of band-resisted barbell exercises over non-banded barbell exercises and transferability to sport performance.","PeriodicalId":170948,"journal":{"name":"International Journal of Strength and Conditioning","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135436772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comparison of Force-Time Metrics Between Countermovement Vertical Jump With and Without an Arm Swing in Professional Male Basketball Players 职业男子篮球运动员臂摆与臂摆对位垂直跳力-时间指标的比较

International Journal of Strength and Conditioning Pub Date : 2023-09-01 DOI: 10.47206/ijsc.v3i1.197

D. Cabarkapa, Nicolas M Philipp, Damjana V. Cabarkapa, Drake A Eserhaut, Andrew C Fry

{"title":"Comparison of Force-Time Metrics Between Countermovement Vertical Jump With and Without an Arm Swing in Professional Male Basketball Players","authors":"D. Cabarkapa, Nicolas M Philipp, Damjana V. Cabarkapa, Drake A Eserhaut, Andrew C Fry","doi":"10.47206/ijsc.v3i1.197","DOIUrl":"https://doi.org/10.47206/ijsc.v3i1.197","url":null,"abstract":"With technological developments over the last decade, a wide range of countermovement vertical jump (CMJ) force-time metrics can be derived from commercially available portable force plate systems. However, it should be noted that how the test is performed can have a substantial impact on the outcome of the assessment. Thus, the purpose of the present study was to determine differences in biomechanical variables between CMJ with and without an arm swing in a cohort of elite athletes. Ten professional male basketball players volunteered to participate in the present study. Following a standardized warm-up procedure, athletes stepped on a uni-axial force plate sampling at 1000 Hz and performed three CMJ without arm swing (i.e., hands on the hips) followed by three CMJ with an arm swing (i.e., arms positioned slightly in the front of the body with elbows flexed at a 90-degree angle). To minimize the possible influence of fatigue, each jump was separated by a 15-30 s rest interval. The findings of the present study indicate phase- specific differences in multiple force-time metrics between the two CMJ testing modalities. While having greater eccentric duration, CMJ with an arm swing had lower eccentric braking and deceleration rate of force development and lower eccentric peak force when compared to CMJ without an arm swing. During the concentric phase of the jump, concentric duration, impulse, peak velocity, and peak power were significantly greater in favor of CMJ with an arm swing. Also, despite longer contraction time, incorporating an arm swing resulted in greater vertical jump heights. Overall, these data describe the CMJ performance of professional male basketball players and provide helpful information for practitioners when designing assessment protocols to monitor athletes’ neuromuscular performance.","PeriodicalId":170948,"journal":{"name":"International Journal of Strength and Conditioning","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127787898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Neuromuscular and Functional Responses Among Males Trained with Free Weights vs. Machines: Implications for Injury Prevention 男性自由举重训练与机器训练的神经肌肉和功能反应:对损伤预防的影响

International Journal of Strength and Conditioning Pub Date : 2023-08-25 DOI: 10.47206/ijsc.v3i1.125

A. Maior, Marco Leandro Martins de Assis

{"title":"Neuromuscular and Functional Responses Among Males Trained with Free Weights vs. Machines: Implications for Injury Prevention","authors":"A. Maior, Marco Leandro Martins de Assis","doi":"10.47206/ijsc.v3i1.125","DOIUrl":"https://doi.org/10.47206/ijsc.v3i1.125","url":null,"abstract":"The purpose of this study was to compare balance, functional performance and isometric hip strength muscle among males practitioners of resistance training (RT) with Free-weights and Machines. Thirty males were recruited and separated into two groups: Free-weights (n = 15) and Machines (n = 15). Free-weights group showed a routine of RE that engaged the whole body with resistance bands, free-weights, dumbbells, and medicine balls. Conversely, machine group trained only exercises on machines. All participants underwent three tests to assess balance, functionality, and isometric muscle strength. All tests were performed in a single assessment session in the following order: Y Balance test; functional performance testing; and maximal isometric hip strength, respectively. The two-way ANOVA yielded main effects for group in the anterior (F1,22= 12.11, p < .002), posteromedial (F1,22= 16.87, p < .0005), posterolateral (F1,22= 15.97, p < .0006) and composite (F1,22= 21.39, p < .0001) in performance during YBT between free-weight vs. machines group for both legs. Single leg step down (SLSD) and Single leg hop (SLH) test demonstrating better functional performance in the free-weight group for both legs (p<.001). Isometric muscle strength of hip abduction and extension showed lower in the machines when compared to free-weight group for both legs. This study showed greater balance, functional performance and isometric muscle strength of hip abduction and extension in males trained with Free-weight. Males trained with machine showed lower functional performance, balance and bilateral asymmetry of the hip extensor muscles strength and risk of injuries.","PeriodicalId":170948,"journal":{"name":"International Journal of Strength and Conditioning","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116773577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Acute Responses Of A Drop-Set Session On Muscular Activation And Its Applicability In Resistance- Trained Individuals 肌肉激活的急性反应及其在阻力训练个体中的适用性

International Journal of Strength and Conditioning Pub Date : 2023-08-18 DOI: 10.47206/ijsc.v3i1.184

B. Ide, Pedro A. B. Fonseca, R. Brenzikofer, Leonardo H. F. Carvalho, Evanisi T. Palomari, Denise V. Macedo

{"title":"Acute Responses Of A Drop-Set Session On Muscular Activation And Its Applicability In Resistance- Trained Individuals","authors":"B. Ide, Pedro A. B. Fonseca, R. Brenzikofer, Leonardo H. F. Carvalho, Evanisi T. Palomari, Denise V. Macedo","doi":"10.47206/ijsc.v3i1.184","DOIUrl":"https://doi.org/10.47206/ijsc.v3i1.184","url":null,"abstract":"We investigated whether performing repetitions to muscular failure (FAIL) during a drop-set would affect muscle activation in trained individuals. Twelve young men performed a drop-set session consisting of 3 sets of two intensity drops (80 to 60 and to 40% of one-repetition maximum [1-RM]) load in a leg press machine. Linear regression between the quadriceps femoris root mean square of surface electromyography (EMGRMS) was employed to observe the initial muscle activation (intercept) and its behavior over the repetitions (slope). The EMGRMS intercept of the first set decreased (p<0.05) according to load reduction (136.8±4.8 at 80%1-RM to 119.3±5.5 and 110.6±5.5 at 60 and 40%1-RM, respectively). Slopes different from zero (p<0.05) were observed at 80 and 60%1-RM during the first set. Remarkably, during the second and third sets, we observed an increased EMGRMS intercept at 60%1-RM (p<0.05), leading to non-significant (p>0.05) differences compared to 80%1-RM. The maximum initial muscle activation occurred at higher loads only, but low loads performed to FAIL may be necessary for increasing and maintaining muscle activation at higher loads. Understanding these acute responses may support coaches and athletes in optimizing strength training responses during drop-set sessions into their periodization.","PeriodicalId":170948,"journal":{"name":"International Journal of Strength and Conditioning","volume":"12 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129767762","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comparisons Of Weekly Training Volumes Across A Season In Collegiate Female Lacrosse Athletes 大学女子曲棍球运动员一个赛季每周训练量的比较

International Journal of Strength and Conditioning Pub Date : 2023-08-11 DOI: 10.47206/ijsc.v3i1.166

M. Wojciechowski, Claire Schumann, J. Bunn

{"title":"Comparisons Of Weekly Training Volumes Across A Season In Collegiate Female Lacrosse Athletes","authors":"M. Wojciechowski, Claire Schumann, J. Bunn","doi":"10.47206/ijsc.v3i1.166","DOIUrl":"https://doi.org/10.47206/ijsc.v3i1.166","url":null,"abstract":"The purpose of this study was to describe the in-season variations of acute:chronic workload ratio (ACWR) of distance, high intensity distance (HID), sprints, accelerations, and decelerations between player positions of a Division I collegiate women’s lacrosse team. Data were collected via wearable microtechnology across a total of 17 games and 64 training sessions on a total of 15 participants (attackers n=5, midfielders n=5, defenders n=5). ACWRs were calculated weekly by dividing the workload from the past seven days by the workload from the past 28 days for each metric. Two repeated measures analyses of variance (RM-ANOVA) were used to compare positional differences and weekly changes in all five metrics for 1) ACWR and 2) weekly training totals. There were several differences in weekly totals and ACWRs across all five metrics evaluated (p<.05), but no positional differences were noted. Apart from the early training weeks, ACWR primarily stayed within the optimal window of 0.8-1.5 to maximize performance and reduce injury risk. These data indicate that there is variation in weekly totals for the main five metrics studied that cause “spikes” and “valleys” in workload. However, the athletes had built enough of a base in their chronic workload that it did not affect their ACWR to move outside of the optimal window. Using this information, coaches and team physicians can more effectively program training not only to optimize performance, but also to limit injuries, fatigue, and lack of fitness.","PeriodicalId":170948,"journal":{"name":"International Journal of Strength and Conditioning","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130781252","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0