Journal of sports science & medicine最新文献

{"title":"Epigenetic Status of The Human <i>MMP11</i> Gene Promoter is Altered in Patellar Tendinopathy.","authors":"Rebecca Rickaby,&nbsp;Louis Y El Khoury,&nbsp;Tom Samiric,&nbsp;Stuart M Raleigh","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Patellar tendinopathy (PT) is a debilitating condition that often affects those who are physically active. Gene variation is known to contribute to human tendinopathy but the role of DNA methylation, as an epigenetic factor, has only recently been discovered. Using a case-control approach, we sought to determine whether differences existed between the methylation status of the <i>MMP11</i> gene promoter in patellar tendinopathy compared to healthy tendon. We used PCR and pyrosequencing to interrogate the methylation profiles of 4 CpG sites (areas of the genome rich in C/G nucleotides) upstream of the <i>MMP11</i> gene in DNA from males with PT (n = 10) and those with healthy tendon (n = 10). We also conducted a correlation analysis to establish whether age influenced methylation in the PT patients and controls. We found a significant (p = 0.045) difference in the methylation status of a single CpG site 65 base pairs (bp) upstream of the <i>MMP11</i> promoter between the PT group and controls. There were no other differences in the extent of <i>MMP11</i> promoter methylation between the two groups. Interestingly, we also found that in controls the degree of methylation at a second CpG site, 55 bp upstream of the first exon, tentatively correlated (r = 0.77, p = 0.009) with age. However, the correlation did not reach significance when a potential outlier was removed. This is the first study to show an epigenetic alteration to a member of the <i>MMP</i> gene family in human patellar tendinopathy. The data add to our understanding of how epigenetics should be considered when developing appropriate risk models.</p>","PeriodicalId":520691,"journal":{"name":"Journal of sports science & medicine","volume":" ","pages":"155-159"},"PeriodicalIF":3.2,"publicationDate":"2019-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6370951/pdf/jssm-18-155.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"36975999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Use of GPS Analysis to Quantify the Internal and External Match Demands of Semi-Elite Level Female Soccer Players during a Tournament.","authors":"Anita Strauss,&nbsp;Martinique Sparks,&nbsp;Cindy Pienaar","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The purpose of this study was to make use of global positioning system technology to quantify the internal and external match demands of sub-elite female soccer players. Secondly, the study aims to describe the magnitude of change of these variables within and between matches over the course of a tournament to determine the effect of player fatigue. Thirty sub-elite female soccer players were assessed throughout a local tournament. Differences in match demands within and between matches were assessed using percent difference, effect size and 90% confidence intervals. One-way ANOVA was used to compare differences in the match demands and running intensities among playing positions and Bonferroni corrections were used to determine differences where significant effects of position were observed. A paired sample t-test in conjunction with the Cohen effect size was used to compare changes in match performance. Total distance covered averaged 5917 m. Midfielders covered the greatest absolute and relative total distances, and achieved the highest low-intensity activity and player load per minute of play. Defenders covered significantly (p ≤ 0.05) less relative distance and low-intensity activity per minute of play compared to midfielders. Forwards covered the greatest distance at high-intensity, while the greatest percentage of time at high-intensity heart rate was measured among the defenders. Within match comparisons revealed that player load decreased significantly (p ≤ 0.05) in the second half (ES: 0.4). Relative distance, low-intensity activity and high-intensity activity also decreased in the second half with possibly trivial to likely small changes. Small to large differences in variables were observed throughout the tournament. The biggest magnitude of change was seen with a large decrease (ES: -1.2) in relative distance covered between match 2 and 5. Despite generally small reductions in performance measures, there is evidence that accumulated fatigue throughout a multi-day tournament would affect performance negatively.</p>","PeriodicalId":520691,"journal":{"name":"Journal of sports science & medicine","volume":" ","pages":"73-81"},"PeriodicalIF":3.2,"publicationDate":"2019-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6370966/pdf/jssm-18-73.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"36984455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stretching Combined with Repetitive Small Length Changes of the Plantar Flexors Enhances Their Passive Extensibility while Not Compromising Strength.","authors":"Naoki Ikeda,&nbsp;Takayuki Inami,&nbsp;Yasuo Kawakami","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Static stretching increases flexibility but can decrease muscle strength; therefore, a method that would avoid the latter has been longed for. In this study, a novel stretching modality was developed that provides repetitive small length changes to the plantar flexor muscles undergoing passive static stretching (minute oscillation stretching). We investigated the effects of minute oscillation stretching on muscle strength and flexibility and its continuance. Isometric plantar flexion strength and maximal ankle joint dorsiflexion angle (dorsiflexion range of motion) were measured in 10 healthy young men (22 ± 2 years) before (pre) and immediately after (post) 3 types of stretching: static stretching, minute oscillation stretching at 15 Hz, and no intervention (control). The dorsiflexion range of motion was also measured at 15, 30, and 60 min post-stretching. Elongation of the medial gastrocnemius and Achilles tendon was determined by ultrasonography. Plantar flexion strength significantly decreased by 4.3 ± 3.5% in static stretching but not in minute oscillation stretching. The dorsiflexion range of motion significantly increased both in static stretching (7.2 ± 8.1%) and minute oscillation stretching (11.2 ± 14.6%), which was accompanied by a significantly larger muscle elongation but not tendon elongation. Elevated dorsiflexion range of motion was maintained until 30 min after minute oscillation stretching, while levels returned to baseline (pre-intervention) 15 min after static stretching. All variables remained unchanged in the control condition. In conclusion, minute oscillation stretching improves extensibility of the muscle belly without decreasing strength. Furthermore, the augmented flexibility to a similar extent to static stretching is retained for 30 min in minute oscillation stretching and within 15 min in static stretching.</p>","PeriodicalId":520691,"journal":{"name":"Journal of sports science & medicine","volume":" ","pages":"58-64"},"PeriodicalIF":3.2,"publicationDate":"2019-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6370965/pdf/jssm-18-58.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"36984453","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Perceptual and Cardiorespiratory Responses to High-Intensity Interval Exercise in Adolescents: Does Work Intensity Matter?","authors":"Adam A Malik,&nbsp;Craig A Williams,&nbsp;Kathryn L Weston,&nbsp;Alan R Barker","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>High-intensity interval exercise (HIIE) may not elicit prominent unpleasant feelings even with elevated perceived exertion and physiological stress in adolescents. However, the influence of different HIIE work intensities on the affective experience and cardiorespiratory responses is unknown. This study examined the acute affective, enjoyment, perceived exertion and cardiorespiratory responses to HIIE with different work intensities in adolescents. Participants (n = 16; 8 boys; age 12.0 ± 0.3 years) performed, on separate days, HIIE conditions consisting of 8 x 1-minute work-intervals at 70%, 85%, or 100% peak power separated by 75 seconds recovery at 20 W. Affect, enjoyment and rating of perceived exertion (RPE) were recorded before, during, and after HIIE. Heart rate (HR) and oxygen uptake were collected during HIIE. Affect declined in all conditions (p < 0.01) but 100%HIIE elicited significantly lower affect than 70%HIIE and 85%HIIE at work-interval 8 (all p < 0.02, ES > 1.74; 70%HIIE = 2.5 ± 0.8; 85%HIIE = 1.1 ± 1.5; 100%HIIE = -1.5 ± 1.4 on feeling scale). Similar enjoyment was evident during and after all conditions (all p > 0.44). RPE was significantly higher during 100%HIIE than 70%HIIE and 85%HIIE across all work-intervals (all p < 0.01, ES > 1.56). The majority of the participants attained ≥90%HR_max during 85%HIIE (87%) and 100%HIIE (100%), but not during 70%HIIE (6%). Affect responses during HIIE are dependent on the intensity of the work-interval and are not entirely negative (unpleasant feelings). Despite similar enjoyment, positive affect experienced during 70%HIIE and 85%HIIE could serve as a strategy to encourage exercise adoption and adherence in adolescents, but only 85%HIIE elicits sufficient HR stimulus to facilitate potential health benefits.</p>","PeriodicalId":520691,"journal":{"name":"Journal of sports science & medicine","volume":" ","pages":"1-12"},"PeriodicalIF":3.2,"publicationDate":"2019-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6370969/pdf/jssm-18-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"36984874","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic Stretching Has Sustained Effects on Range of Motion and Passive Stiffness of the Hamstring Muscles.","authors":"Masahiro Iwata,&nbsp;Ayano Yamamoto,&nbsp;Shingo Matsuo,&nbsp;Genki Hatano,&nbsp;Manabu Miyazaki,&nbsp;Taizan Fukaya,&nbsp;Mitsuhiro Fujiwara,&nbsp;Yuji Asai,&nbsp;Shigeyuki Suzuki","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Dynamic stretching (DS) is often performed during warm-up to help avoid hamstring muscle injuries, increase joint flexibility, and optimize performance. We examined the effects of DS of the hamstring muscles on passive knee extension range of motion (ROM), passive torque (PT) at the onset of pain (as a measure of stretch tolerance), and passive stiffness of the muscle-tendon unit over an extended period after stretching. Twenty-four healthy subjects participated, with 12 each in the experimental and control groups. Stretching was performed, and measurements were recorded using an isokinetic dynamometer pre-intervention, and at 0, 15, 30, 45, 60, 75, and 90 min post-intervention. DS consisted of ten 30-s sets of 15 repetitions of extension and relaxation of the hamstrings. ROM increased significantly (range, 7%-10%) immediately after DS, and the increase was sustained over 90 min. PT at the onset of pain also increased immediately by 10% but returned to baseline by 30 min. Passive stiffness decreased significantly (range, 7.9%-16.7%) immediately after DS, and the decrease was sustained over 90 min. Post-DS values were normalized to pre-DS values for the respective outcomes in both groups. ROM was significantly higher (range, 7.4%-10%) and passive stiffness was significantly lower (range, 5.4%-14.9%) in the experimental group relative to the control group at all time points. Normalized PT values at the onset of pain were significantly higher in the experimental group at 0-15 min than in the controls, but the differences were smaller at 30-45 min and not significant thereafter. We conclude that DS increases ROM and decreases passive stiffness in a sustained manner, and increases PT at the onset of pain for a shorter period. Overall, our results indicate that when performed prior to exercise, DS is beneficial for the hamstring muscles in terms of increasing flexibility and reducing stiffness.</p>","PeriodicalId":520691,"journal":{"name":"Journal of sports science & medicine","volume":" ","pages":"13-20"},"PeriodicalIF":3.2,"publicationDate":"2019-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6370952/pdf/jssm-18-13.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"36984875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of adaptive paced cardiolocomotor synchronization during running: a preliminary study.","authors":"Bill Phillips,&nbsp;Yi Jin","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Cardiolocomotor synchronization (CLS) has been well established for individuals engaged in rhythmic activity, such as walking, running, or cycling. When frequency of the activity is at or near the heart rate, entrainment occurs. CLS has been shown in many cases to improve the efficiency of locomotor activity, improving stroke volume, reducing blood pressure variability, and lowering the oxygen uptake (VO2). Instead of a 1:1 frequency ratio of activity to heart rate, an investigation was performed to determine if different harmonic coupling at other simple integer ratios (e.g. 1:2, 2:3, 3:2) could achieve any performance benefits. CLS was ensured by pacing the stride rate according to the measured heartbeat (i.e., adaptive paced CLS, or forced CLS). An algorithm was designed that determined the simplest ratio (lowest denominator) that, when multiplied by the heart rate will fall within an individualized, predetermined comfortable pacing range for the user. The algorithm was implemented on an iPhone 4, which generated a 'tick-tock' sound through the iPhone's headphones. A sham-controlled crossover study was performed with 15 volunteers of various fitness levels. Subjects ran a 3 mile (4.83 km) simulated training run at their normal pace on two consecutive days (randomized one adaptive pacing, one sham). Adaptive pacing resulted in faster runs run times, with subjects running an average of 26:03 ± 3:23 for adaptive pacing and 26:38 ± 3:31 for sham (F = 5.46, p < 0.05). The increase in heart rate from the start of the race as estimated by an exponential time constant was significantly longer during adaptive pacing, τ = 0.99 ± 0.30, compared to sham, τ = 1.53 ± 0.34 (t = -6.62, p < 0.01). Eighty-seven percent of runners found it easy to adjust their stride length to match the pacing signal with seventy-nine percent reporting that pacing helped their performance. These results suggest that adaptive paced CLS may have a beneficial effect on running performance and may be useful as a training aid. Key PointsSham-controlled crossover study using 15 experienced runners running 3 miles (4.83 km).Adaptive CLS pacing resulted in statistically significant 35 second average decrease in run-time (p < 0.05).Increase in heart rate during the run was significantly slower during adaptive pacing (p < 0.01). </p>","PeriodicalId":520691,"journal":{"name":"Journal of sports science & medicine","volume":" ","pages":"381-7"},"PeriodicalIF":3.2,"publicationDate":"2013-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3772578/pdf/jssm-12-381.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40255700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of nordic walking compared to conventional walking and band-based resistance exercise on fitness in older adults.","authors":"Nobuo Takeshima,&nbsp;Mohammod M Islam,&nbsp;Michael E Rogers,&nbsp;Nicole L Rogers,&nbsp;Naoko Sengoku,&nbsp;Daisuke Koizumi,&nbsp;Yukiko Kitabayashi,&nbsp;Aiko Imai,&nbsp;Aiko Naruse","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The purpose of this study was to compare the effects of Nordic walking with conventional walking and band-based resistance exercise on functional fitness, static balance and dynamic balance in older adults. Volunteers (n = 65) were divided into four groups: Nordic walking (NW), conventional walking (CW), resistance (RES), and control. Each group performed activity 50-70 min·day(-1) (warm-up 10-15 min, main exercise 30-40, and cool down 10-15 min), 3 days·week(-1) (NW and CW) or 2 day·week(-1) (RES) for 12 wks. Upper-body strength improved (p < 0. 05) in the RES (22.3%) and the NW (11.6%) groups compared to the CW and control groups. Cardio- respiratory fitness improved more in the NW (10.9%) and CW (10.6%) groups compared to the RES and control groups. Upper- and lower-body flexibility also improved in all exercise groups compared to the control group. There were no improvements in balance measures in any group. While all modes of exercise improved various components of fitness, Nordic walking provided the best well-rounded benefits by improving upper-body strength, cardiovascular endurance, and flexibility. Therefore, Nordic walking is recommended as an effective and efficient mode of concurrent exercise to improve overall functional fitness in older adults. Key PointsNordic walking, conventional walking, and resistance training are beneficial for older adults.Nordic walking and conventional walking both improve cardio-respiratory fitness while resistance training does not.Nordic walking provides additional benefits in upper-body muscular strength compared to conventional walking.Nordic walking is an effective and efficient mode of exercise to improve overall fitness in older adults. </p>","PeriodicalId":520691,"journal":{"name":"Journal of sports science & medicine","volume":" ","pages":"422-30"},"PeriodicalIF":3.2,"publicationDate":"2013-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3772584/pdf/jssm-12-422.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40257177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Can a Specific Neck Strengthening Program Decrease Cervical Spine Injuries in a Men's Professional Rugby Union Team? A Retrospective Analysis.","authors":"Robert Naish,&nbsp;Angus Burnett,&nbsp;Sally Burrows,&nbsp;Warren Andrews,&nbsp;Brendyn Appleby","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>Cervical spine injuries in Rugby Union are a concerning issue at all levels of the game. The primary aim of this retrospective analysis conducted in a professional Rugby Union squad was to determine whether a 26-week isometric neck strengthening intervention program (13-week strengthening phase and 13-week maintenance phase) was effective in reducing the number and severity of cervical spine injuries. The secondary aim was to determine whether at week five, where the program had been the similar for all players, there was increased isometric neck strength. All 27 players who were common to both the 2007-2008 and 2008-2009 seasons were included in this analysis and data was extracted from a Sports Medicine/Sports Science database which included the squad's injury records. Primary outcome variables included; the number of cervical spine injuries and the severity of these injuries as determined by the total number of days lost from training and competition. Secondary outcome variables included isometric neck strength in flexion, extension and left and right lateral flexion. Using non-parametric statistical methods, no significant differences were evident for the total number of cervical spine injuries (n = 8 in 2007-2008, n = 6 in 2008-2009) or time loss due to these injuries (100 days in 2007-2008, 40 days in 2008-2009). However, a significant (p = 0.03) reduction in the number of match injuries was evident from 2007-2008 (n = 11) to 2008-09 (n = 2). Non-significant increases in isometric neck strength were found in all directions examined. A significant reduction in the number of match injuries was evident in this study. However, no other significant changes to primary outcome variables were achieved. Further, no significant increases in isometric neck strength were found in this well-trained group of professional athletes. Key PointsWhile many authors have proposed that neck strengthening could be an effective strategy in preventing cervical spine injuries in Rugby Union, there is currently little information in the literature pertaining to how such a study might be conducted.A significant decrease in the number of injuries recorded in matches can be achieved using a specific neck strengthening program at the elite level.In an elite rugby union team as investigated in this study a significant increase in neck strength is difficult to achieve in a short period of time such as five weeks. </p>","PeriodicalId":520691,"journal":{"name":"Journal of sports science & medicine","volume":" ","pages":"542-50"},"PeriodicalIF":3.2,"publicationDate":"2013-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3772600/pdf/jssm-12-542.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40258515","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Energy system contributions during incremental exercise test.","authors":"Rômulo Bertuzzi,&nbsp;Eduardo M F Nascimento,&nbsp;Rodrigo P Urso,&nbsp;Mayara Damasceno,&nbsp;Adriano E Lima-Silva","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The main purpose of this study was to determine the relative contributions of the aerobic and glycolytic systems during an incremental exercise test (IET). Ten male recreational long-distance runners performed an IET consisting of three-minute incremental stages on a treadmill. The fractions of the contributions of the aerobic and glycolytic systems were calculated for each stage based on the oxygen uptake and the oxygen energy equivalents derived by blood lactate accumulation, respectively. Total metabolic demand (WTOTAL) was considered as the sum of these two energy systems. The aerobic (WAER) and glycolytic (WGLYCOL) system contributions were expressed as a percentage of the WTOTAL. The results indicated that WAER (86-95%) was significantly higher than WGLYCOL (5-14%) throughout the IET (p < 0.05). In addition, there was no evidence of the sudden increase in WGLYCOL that has been previously reported to support to the \"anaerobic threshold\" concept. These data suggest that the aerobic metabolism is predominant throughout the IET and that energy system contributions undergo a slow transition from low to high intensity. Key PointsThe aerobic metabolism contribution is the predominant throughout the maximal incremental test.The speed corresponding to the aerobic threshold can be considered the point in which aerobic metabolism reaches its maximal contribution.Glycolytic metabolism did not contribute largely to the energy expenditure at intensities above the anaerobic threshold. </p>","PeriodicalId":520691,"journal":{"name":"Journal of sports science & medicine","volume":" ","pages":"454-60"},"PeriodicalIF":3.2,"publicationDate":"2013-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3772588/pdf/jssm-12-454.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40259105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of the 11+ and Harmoknee Warm-up Programs on Physical Performance Measures in Professional Soccer Players.","authors":"Abdolhamid Daneshjoo,&nbsp;Abdul Halim Mokhtar,&nbsp;Nader Rahnama,&nbsp;Ashril Yusof","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The purpose of this study was to examine the effects of the 11+ and HarmoKnee warm-up programs on performance measures in professional soccer players. Thirty-six male professional soccer players (age: 18.9 ± 1.4 years) were divided into 3 groups, the 11+, HarmoKnee and control group (n = 12 per group). The experimental groups performed the programs 3 times per week for 2 months (24 sessions), whereas the control group only performed their regular soccer training. The performance tests carried out were: 10m speed tests with and without a ball, 20m single sprint, vertical jump, Wall-Volley and Illinois agility tests. The 11+ group demonstrated significant increases from pre-to-post time points in the vertical jump (3.7%), Wall- Volley (5.4%) and Illinois agility tests (1.7%), while the HarmoKnee group showed a significant increase in Wall-Volley test, with a 5.2% increase. The repeated measures analysis revealed differences between the groups (large effect size) in the 11+ and HarmoKnee groups, compared to the control group, in 10m speed tests with and without a ball, 20m single sprint and Illinois agility tests (p < 0.05). Thus 8-weeks performing the 11+ warm-up program can enhance jump height, agility and soccer skill while the HarmoKnee program generally only improves soccer skill in young professional male soccer players. Key PointsThe 11+ improves performance by means of Illinois agility, vertical jump and Wall-Volley tests whereas HarmoKnee improves Wall-Volley test. Incorporating 11+ as a part of the warm-up program by the young teams would be beneficial in agility, leg power and soccer skill respectively.Further modification of both programs may be required to fully realize the players' speed performance potential.Data from this research can be helpful for soccer trainers in choosing programs to enhance performances in young male professional soccer players. </p>","PeriodicalId":520691,"journal":{"name":"Journal of sports science & medicine","volume":" ","pages":"489-96"},"PeriodicalIF":3.2,"publicationDate":"2013-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3772593/pdf/jssm-12-489.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40259110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}