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Vigh-Larsen JF, Junge N, Cialdella-Kam L, Tomás R, Young L, Krustrup P, Mohr M, Nybo L. Testing in Intermittent Sports-Importance for Training and Performance Optimization in Adult Athletes. Med Sci Sports Exerc 2024; 56:1505-1537. [PMID: 39004796 DOI: 10.1249/mss.0000000000003442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/16/2024]
Abstract
ABSTRACT Performance in intermittent sports relies on the interplay between multiple physiological systems determining the capacity to perform short explosive efforts as well as repeated intense actions with limited recovery over the course of an entire game. Testing should reflect these demands to allow for sport- and position-specific capacity analyses that eventually may translate into optimized training and improved performance. This may include individual load management and optimized training prescription, intensity targeting for specific positions or individual athletes, as well as benchmarking for monitoring of training progression and enhanced engagement of athletes. This review provides an overview of available tests in different exercise domains identified as relevant (from assessment of single explosive actions to intermittent endurance capacity), forming the basis for recommendations on how to compose a comprehensive yet feasible test battery that may be integrated into the seasonal competition and training plan. The test procedures should cover the performance spectrum of relevance for the individual athlete-also in team sports to account for positional differences. We emphasize the benefits of sport-specific tests, highlight parameters of importance for test standardization, and discuss how the applied test battery may be supplemented with secondary tests directed toward specific energy systems to allow for more in-depth analyses when required (e.g., in terms of an underperforming athlete). The synergy between testing and tracking of match performance (utilizing time-motion or global positioning systems) is highlighted, and although tracking cannot substitute for testing, combining the tools may provide a comprehensive overview of the physiological demands and performance during competition contextualized to the athletes' maximal exercise capacity.
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Affiliation(s)
| | - Nicklas Junge
- Department of Nutrition, Exercise and Sport Sciences, University of Copenhagen, Copenhagen, DENMARK
| | - Lynn Cialdella-Kam
- Warfighter Performance Department, Naval Health Research Center, San Diego, CA
| | - Rita Tomás
- Portugal Football School, Federação Portuguesa de Futebol Avenida das Seleções, Oeiras, PORTUGAL
| | - Laura Young
- American College of Sports Medicine, Indianapolis, IN
| | | | | | - Lars Nybo
- Department of Nutrition, Exercise and Sport Sciences, University of Copenhagen, Copenhagen, DENMARK
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Thieschäfer L, Dos'Santos T, Büsch D. Cutting Technique Modification: A Way to Improve Movement Quality and Develop Agility in Youth? J Strength Cond Res 2024:00124278-990000000-00502. [PMID: 39074239 DOI: 10.1519/jsc.0000000000004837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/31/2024]
Abstract
Abstract
Thieschäfer, L, Dos’Santos, T, and Büsch, D. Cutting technique modification: a way to improve movement quality and develop agility in youth? J Strength Cond Res XX(X): 000–000, 2024—High-quality cutting technique is essential for agility development and safer cuttings in adolescent athletes. Certain sidestep techniques and kinematics are characteristic of high movement quality and are associated with both, faster performance and lower knee joint loading (i.e., reduced anterior cruciate ligament injury risk). The aim of this study was to determine the effects of a 6-week, side step, technique modification training intervention targeting specific kinematics on agility performance and movement quality. Twenty-two adolescent American football players were recruited for a nonrandomized, controlled, intervention study. For 6 weeks, an intervention group (IG) of 11 players participated in 25-minute cutting technique training sessions integrated into team training twice a week, whereas a control group (CG) of 11 players continued their usual training routine. Agility performance was assessed based on percentage-based change of direction deficit (CODDp) obtained during reactive agility tests at 45° and 90° angles. The Cutting Movement Assessment Score (CMAS) qualitative screening tool was used to assess 2D high-speed videos of the cuts for movement quality. The significance level was set at α = 0.01. The intervention effectively altered players' sidestep technique irrespective of cutting angle with large time × group interaction effects observed for CMAS (
= 0.82). Statistical and practical significant improvements in CMAS pre-to-post intervention were evident in the IG (−2.30 ≤ g ≤ −1.75; 313.87 ≤ BF10 ≤ 2,342.00), whereas deteriorations were found in the CG for 90° (g = 1.38; BF10 = 64.21). However, in both groups, no statistically significant differences in CODDp were observed pre-to-post intervention (0.019 ≤ p ≤ 0.586; 0.34 ≤ BF10 ≤ 3.59). The cutting technique modification training meaningfully improved movement quality, without negatively affecting agility performance, and can be used by practitioners to foster a safe technical foundation for subsequent agility development in adolescent athletes.
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Affiliation(s)
- Lutz Thieschäfer
- Department of Sport and Training, Institute of Sport Science, School of Humanities and Social Sciences, Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany; and
| | - Thomas Dos'Santos
- Department of Sport and Exercise Sciences, Manchester Institute of Sport, Manchester Metropolitan University, Manchester, United Kingdom
| | - Dirk Büsch
- Department of Sport and Training, Institute of Sport Science, School of Humanities and Social Sciences, Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany; and
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McKay BA, Delaney JA, Simpkin A, Larkin T, Murray A, Daniels D, Pedlar CR, Sampson JA. Objective Measures of Strain and Subjective Muscle Soreness Differ Between Positional Groups and Season Phases in American College Football. Int J Sports Physiol Perform 2023; 18:625-633. [PMID: 37059425 DOI: 10.1123/ijspp.2022-0347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 01/27/2023] [Accepted: 03/03/2023] [Indexed: 04/16/2023]
Abstract
PURPOSE To assess objective strain and subjective muscle soreness in "Bigs" (offensive and defensive line), "Combos" (tight ends, quarterbacks, line backers, and running backs), and "Skills" (wide receivers and defensive backs) in American college football players during off-season, fall camp, and in-season phases. METHODS Twenty-three male players were assessed once weekly (3-wk off-season, 4-wk fall camp, and 3-wk in-season) for hydroperoxides (free oxygen radical test [FORT]), antioxidant capacity (free oxygen radical defense test [FORD]), oxidative stress index (OSI), countermovement-jump flight time, Reactive Strength Index (RSI) modified, and subjective soreness. Linear mixed models analyzed the effect of a 2-within-subject-SD change between predictor and dependent variables. RESULTS Compared to fall camp and in-season phases, off-season FORT (P ≤ .001 and <.001), FORD (P ≤ .001 and <.001), OSI (P ≤ .001 and <.001), flight time (P ≤ .001 and <.001), RSI modified (P ≤ .001 and <.001), and soreness (P ≤ .001 and <.001) were higher for "Bigs," whereas FORT (P ≤ .001 and <.001) and OSI (P = .02 and <.001) were lower for "Combos." FORT was higher for "Bigs" compared to "Combos" in all phases (P ≤ .001, .02, and .01). FORD was higher for "Skills" compared with "Bigs" in off-season (P = .02) and "Combos" in-season (P = .01). OSI was higher for "Bigs" compared with "Combos" (P ≤ .001) and "Skills" (P = .01) during off-season and to "Combos" in-season (P ≤ .001). Flight time was higher for "Skills" in fall camp compared with "Bigs" (P = .04) and to "Combos" in-season (P = .01). RSI modified was higher for "Skills" during off-season compared with "Bigs" (P = .02) and "Combos" during fall camp (P = .03), and in-season (P = .03). CONCLUSION Off-season American college football training resulted in higher objective strain and subjective muscle soreness in "Bigs" compared with fall camp and during in-season compared with "Combos" and "Skills" players.
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Affiliation(s)
- Benjamin A McKay
- Centre of Medical and Exercise Physiology, School of Medicine, University of Wollongong, Wollongong, NSW,Australia
- Athletics Department, University of Oregon, Eugene, OR,USA
| | | | - Andrew Simpkin
- School of Mathematical and Statistical Sciences, National University of Ireland, Galway,Ireland
| | - Theresa Larkin
- Centre of Medical and Exercise Physiology, School of Medicine, University of Wollongong, Wollongong, NSW,Australia
- Illawarra Health and Medical Research Institute, Wollongong, NSW,Australia
| | - Andrew Murray
- Physical Education & Health Sciences, University of Edinburgh, Edinburgh,United Kingdom
| | - Diarmuid Daniels
- Orreco Ltd, Business Innovation Unit, National University of Ireland, Galway,Ireland
| | - Charles R Pedlar
- Orreco Ltd, Business Innovation Unit, National University of Ireland, Galway,Ireland
- Faculty of Sport, Allied Health and Performance Sciences, St Mary's University, London,United Kingdom
- Division of Surgery and Interventional Science, University College London, London,United Kingdom
| | - John A Sampson
- Centre of Medical and Exercise Physiology, School of Medicine, University of Wollongong, Wollongong, NSW,Australia
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Food Insecurity among a Cohort of Division I Student-Athletes. Nutrients 2022; 14:nu14214703. [PMID: 36364965 PMCID: PMC9655568 DOI: 10.3390/nu14214703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 10/29/2022] [Accepted: 11/04/2022] [Indexed: 11/09/2022] Open
Abstract
Background: Though the vulnerability of college students to food insecurity is well established, there is a paucity of studies focusing on the prevalence of food insecurity among student-athletes. Methods: A cross-sectional survey was conducted with collegiate athletes in the northwestern United States via an anonymous online survey. Food security status was assessed using the 10-item US Department of Agriculture Adult Food Security Survey. Results: Participating athletes (45/307, 14%) were primarily White, non-Hispanic (78%) females (73%) who lived and consumed meals off-campus (62% and 69%, respectively). Food insecurity was more prevalent among collegiate athletes than the general university population, 60% vs. 42%, respectively. Being a track or football athlete significantly predicted food security status (p = 0.002, p < 0.001, respectively). The risk for food insecurity was higher among collegiate football players (effect size, η2 = 0.86) compared with track athletes (effect size, η2 = 0.40). Conclusion: A statistically significant risk for food insecurity emerged among members of the football team. Factors contributing to disparate rates of food insecurity among college populations were explored and unique considerations for collegiate athletes discussed.
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Mamon MA, Olthof SBH, Burns GT, Lepley AS, Kozloff KM, Zernicke RF. Position-Specific Physical Workload Intensities in American Collegiate Football Training. J Strength Cond Res 2022; 36:420-426. [PMID: 35080203 DOI: 10.1519/jsc.0000000000004174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
ABSTRACT MamonJr, MA, Olthof, SBH, Burns, GT, Lepley, AS, Kozloff, KM, and Zernicke, RF. Position-specific physical workload intensities in American collegiate football training. J Strength Cond Res 36(2): 420-426, 2022-Quantifying player training loads allows football coaching staff to make informed adjustments to the volume and intensity of training. Physical workload intensity in American football practices have not been extensively quantified. The current study examined physical workload intensities across positions in American collegiate football during training. Data from player tracking technology (Catapult Vector) were collected from 72 American football players (National Collegiate Athletic Association Division I) during in-season practices. Players were involved in individualized skill (indy), team playbook (team), and special team (ST) drills during practice and analyzed for their specialist offensive or defensive role (e.g., linebacker or wide receiver). Player running (i.e., high-speed running and sprint) and accelerations (i.e., high-intensity PlayerLoad and high-intensity inertial movement analysis) per minute were of interest. Drill type and practice day had significant effects on all workload intensity metrics (p < 0.01), but not position. Greater running intensities were seen in ST drills compared with other drill types. Tuesday practice sessions had greater overall intensities compared with other days. Interaction effect of position and drill type was significant (p < 0.001) for all intensity metrics, indicating that position groups exhibited unique workload responses to the drill types. Drill type and practice day interaction effect was significant for all intensity metrics (p < 0.01). The findings may be informative for coaches to tailor physical workloads of practice drills for positional roles in preparation for games and practices. Player tracking technology can add value for strength and conditioning coaches to adjust training programs based on position-specific on-field demands of players.
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Affiliation(s)
- Mark A Mamon
- School of Kinesiology, University of Michigan, Ann Arbor, Michigan
| | - Sigrid B H Olthof
- School of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom.,Exercise and Sport Science Initiative, University of Michigan, Ann Arbor, Michigan; and
| | - Geoffrey T Burns
- Exercise and Sport Science Initiative, University of Michigan, Ann Arbor, Michigan; and
| | - Adam S Lepley
- School of Kinesiology, University of Michigan, Ann Arbor, Michigan.,Exercise and Sport Science Initiative, University of Michigan, Ann Arbor, Michigan; and
| | - Kenneth M Kozloff
- Exercise and Sport Science Initiative, University of Michigan, Ann Arbor, Michigan; and.,Departments of Orthopedic Surgery and Biomedical Engineering, University of Michigan, Ann Arbor, Michigan
| | - Ronald F Zernicke
- School of Kinesiology, University of Michigan, Ann Arbor, Michigan.,Exercise and Sport Science Initiative, University of Michigan, Ann Arbor, Michigan; and.,Departments of Orthopedic Surgery and Biomedical Engineering, University of Michigan, Ann Arbor, Michigan
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Mann JB, Mayhew JL, Dos Santos ML, Dawes JJ, Signorile JF. Momentum, Rather Than Velocity, Is a More Effective Measure of Improvements in Division IA Football Player Performance. J Strength Cond Res 2022; 36:551-557. [PMID: 35080206 DOI: 10.1519/jsc.0000000000004206] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
ABSTRACT Mann, JB, Mayhew, JL, Dos Santos, ML, Dawes, JJ, and Signorile, JF. Momentum, rather than velocity, is a more effective measure of improvements in Division IA football player performance. J Strength Cond Res 36(2): 551-557, 2022-Speed, or the time to complete straight runs or agility drills, is commonly used to assess performance in collegiate American football players. However, it is common for players' speeds to plateau by the second year of eligibility, whereas their body masses continue to increase. The purpose of this study was to track change in speed, body mass, and momentum (body mass · velocity), across Division 1 football players' 4-year careers (n = 512). Complete data were derived for the 40-yd sprint (n = 82), the proagility shuttle (n = 73), and the L drill (n = 73) from the same NCAA Division 1 team over a 15-year period. Significant changes were seen for velocity between year 1 and the next 3 playing years (p < 0.05), with no differences between years 2 and 4, whereas body mass increased significantly across all playing years (p < 0.05). Further momentum increased across all years for all tests (p < 0.0001). These results indicate the importance of including changes in body mass when evaluating performances during sprints and change of direction drills. Our results also suggest that using sprint or agility drill times to evaluate playing potential across football players' collegiate careers may be ineffective and can provide players with a false and disheartening picture of their improvements across their careers. Momentum, which incorporates training-induced increases in both speed and body mass, would be a more relevant and supportive measure of players' improvements. In addition, the simple computation of this variable, using existing speed and body mass data, may be an important addition to the National Football League combine as a measure of playing potential in the professional game.
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Affiliation(s)
- J Bryan Mann
- Department of Kinesiology and Sport Sciences, University of Miami, Coral Gables, Florida
| | - Jerry L Mayhew
- Department of Health and Exercise Sciences, Truman State University, Kirksville, Missouri; and
| | | | - J Jay Dawes
- Applied Exercise Science Department, Oklahoma State University, Stillwater, Oklahoma
| | - Joseph F Signorile
- Department of Kinesiology and Sport Sciences, University of Miami, Coral Gables, Florida
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Torres-Ronda L, Beanland E, Whitehead S, Sweeting A, Clubb J. Tracking Systems in Team Sports: A Narrative Review of Applications of the Data and Sport Specific Analysis. SPORTS MEDICINE - OPEN 2022; 8:15. [PMID: 35076796 PMCID: PMC8789973 DOI: 10.1186/s40798-022-00408-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 01/02/2022] [Indexed: 01/26/2023]
Abstract
Seeking to obtain a competitive advantage and manage the risk of injury, team sport organisations are investing in tracking systems that can quantify training and competition characteristics. It is expected that such information can support objective decision-making for the prescription and manipulation of training load. This narrative review aims to summarise, and critically evaluate, different tracking systems and their use within team sports. The selection of systems should be dependent upon the context of the sport and needs careful consideration by practitioners. The selection of metrics requires a critical process to be able to describe, plan, monitor and evaluate training and competition characteristics of each sport. An emerging consideration for tracking systems data is the selection of suitable time analysis, such as temporal durations, peak demands or time series segmentation, whose best use depends on the temporal characteristics of the sport. Finally, examples of characteristics and the application of tracking data across seven popular team sports are presented. Practitioners working in specific team sports are advised to follow a critical thinking process, with a healthy dose of scepticism and awareness of appropriate theoretical frameworks, where possible, when creating new or selecting an existing metric to profile team sport athletes.
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Affiliation(s)
- Lorena Torres-Ronda
- Institute for Health and Sport, Victoria University, Melbourne, Australia.
- Spanish Basketball Federation, Madrid, Spain.
| | | | - Sarah Whitehead
- Carnegie School of Sport, Leeds Beckett University, Leeds, UK
- Leeds Rhinos Netball, Leeds, UK
| | - Alice Sweeting
- Institute for Health and Sport, Victoria University, Melbourne, Australia
| | - Jo Clubb
- School of Sport, Exercise and Rehabilitation, University of Technology Sydney, Sydney, Australia
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8
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Larose D, Panahi S, Jacob R, Drapeau V. Evaluation of a randomized nutrition intervention combining nutrition education and cooking workshops on dietary intakes and psychosocial determinants of performance in university football athletes. Facets (Ott) 2022. [DOI: 10.1139/facets-2021-0140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Although nutrition influences performance, many athletes, including football players, do not meet nutritional requirements for their sport. The objective of this study was to determine the impact of a nutrition intervention combining nutrition education and cooking workshops on nutrition knowledge, intention, and perceived behavioral control in the preparation of healthy meals, dietary intakes, and diet quality in male university football players. Athletes ( n = 23; age: 22 ± 1 year) were randomly assigned to an intervention (2 h/week) ( n = 13) or control group ( n = 10) over three weeks. Questionnaires were completed before (pre), immediately after (post 1), and two months after the intervention (post 2). Dietary intakes and diet quality were evaluated from three web-based 24-h dietary recalls per visit. Mixed linear models for repeated measures with Tukey’s post hoc test were performed to determine the effects of the intervention on all outcomes. There was a group by time interaction for nutrition knowledge ( p = 0.002) that was higher immediately after and two months after the intervention compared to the control group. No differences on other outcomes were observed. Combining nutrition education and cooking workshops improved nutrition knowledge, but did not affect intention and perceived behavioral control in the preparation of healthy meals, dietary intakes, and diet quality in male university football athletes.
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Affiliation(s)
- David Larose
- Department of Kinesiology, Université Laval, Québec, QC G1V 0A6, Canada
- Quebec Heart and Hung Institute Research Center, Université Laval, Québec, QC G1V 0A6, Canada
- Centre de recherche Nutrition, Santé et Société (NUTRISS), Institute of Nutrition and Functional Foods (INAF), Université Laval, Québec, QC G1V 0A6, Canada
- Centre de recherche interuniversitaire sur la formation et la profession enseignante (CRIFPE), Université Laval, Québec, QC G1V 0A6, Canada
| | - Shirin Panahi
- Department of Kinesiology, Université Laval, Québec, QC G1V 0A6, Canada
- Quebec Heart and Hung Institute Research Center, Université Laval, Québec, QC G1V 0A6, Canada
- Centre de recherche Nutrition, Santé et Société (NUTRISS), Institute of Nutrition and Functional Foods (INAF), Université Laval, Québec, QC G1V 0A6, Canada
- Centre de recherche interuniversitaire sur la formation et la profession enseignante (CRIFPE), Université Laval, Québec, QC G1V 0A6, Canada
- Department of Physical Education, Université Laval, Québec, QC G1V 0A6, Canada
| | - Raphaëlle Jacob
- Quebec Heart and Hung Institute Research Center, Université Laval, Québec, QC G1V 0A6, Canada
- Centre de recherche Nutrition, Santé et Société (NUTRISS), Institute of Nutrition and Functional Foods (INAF), Université Laval, Québec, QC G1V 0A6, Canada
- Centre de recherche interuniversitaire sur la formation et la profession enseignante (CRIFPE), Université Laval, Québec, QC G1V 0A6, Canada
- School of Nutrition, Université Laval, Québec, QC G1V 0A6, Canada
| | - Vicky Drapeau
- Quebec Heart and Hung Institute Research Center, Université Laval, Québec, QC G1V 0A6, Canada
- Centre de recherche Nutrition, Santé et Société (NUTRISS), Institute of Nutrition and Functional Foods (INAF), Université Laval, Québec, QC G1V 0A6, Canada
- Centre de recherche interuniversitaire sur la formation et la profession enseignante (CRIFPE), Université Laval, Québec, QC G1V 0A6, Canada
- Department of Physical Education, Université Laval, Québec, QC G1V 0A6, Canada
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Khalil LS, Lindsay-Rivera KG, Abbas MJ, Shah S, Tandron M, Ferris A, Okoroha KR. Game Utilization and Performance Following RTP From ACL Reconstruction Does not Influence a Subsequent Second ACL Injury in National Football League Players. Arthrosc Sports Med Rehabil 2021; 3:e1377-e1385. [PMID: 34746844 PMCID: PMC8551403 DOI: 10.1016/j.asmr.2021.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 07/05/2021] [Indexed: 11/16/2022] Open
Abstract
Purpose The purpose of this study is to evaluate differences in game utilization or performance following primary anterior cruciate ligament (ACL) reconstruction between National Football League (NFL) players with and without a second ACL injury. Methods NFL players who underwent ACL reconstruction between 2013 and 2017 were identified. Players were classified as having one injury (“tear”) or having later sustained a subsequent second (reinjury or contralateral) ACL injury (“retear”). Players were excluded if they tore their ACL prior to the NFL, did not return to play (RTP), did not play the season before injury, or had concomitant injuries. Demographic characteristics, game utilization statistics, and season approximate value (SAV) performance metrics were recorded. Statistical analysis compared data after RTP from primary ACL reconstruction (seasons +1, +2, and +3) relative to the season before injury (season −1) between cohorts using mean differences and relative percentages. Results Analysis included a total of 45 players, 32 in the “tear” group and 13 in the “retear” group. Demographics, level of play, and time to RTP after primary ACL reconstruction did not differ between the groups (P > .05). Tear and retear groups demonstrated similar utilization and performance metrics the season prior to injury (−1) and the 3 seasons following RTP (season of injury is “0”). Both groups had a similar decrease (relative percentage) in games played and started, snap counts, and SAV during the 3 seasons following RTP compared to baseline (P > .05). The draft pick position was correlated with the relative percentage of games started the first season after RTP (r = .6, P = .02). Conclusions Game utilization and performance metrics following ACL reconstruction were not associated with a subsequent second ACL injury. Players with a higher draft pick position were more likely to return to the starting lineup following primary ACL reconstruction. Ultimately, player game utilization and performance following primary ACL reconstruction is not predictive of a subsequent second ACL injury. Level of Evidence Level III, retrospective case-control study
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Affiliation(s)
- Lafi S Khalil
- Henry Ford Hospital, Department of Orthopaedic Surgery, Detroit, Michigan, U.S.A
| | | | - Muhammad J Abbas
- Henry Ford Hospital, Department of Orthopaedic Surgery, Detroit, Michigan, U.S.A
| | - Sabin Shah
- Henry Ford Hospital, Department of Orthopaedic Surgery, Detroit, Michigan, U.S.A
| | - Marissa Tandron
- Wayne State University, School of Medicine, Detroit, Michigan, U.S.A
| | - Albert Ferris
- Wayne State University, School of Medicine, Detroit, Michigan, U.S.A
| | - Kelechi R Okoroha
- Mayo Clinic, Department of Orthopedic Surgery, Minneapolis, Minnesota, U.S.A
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The Association Between Alterations in Redox Homeostasis, Cortisol, and Commonly Used Objective and Subjective Markers of Fatigue in American Collegiate Football. Int J Sports Physiol Perform 2021; 16:1851-1857. [PMID: 34051699 DOI: 10.1123/ijspp.2020-0933] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 02/22/2021] [Accepted: 03/18/2021] [Indexed: 11/18/2022]
Abstract
PURPOSE To assess associations between a free oxygen radical test (FORT), free oxygen radical defense test (FORD), oxidative stress index, urinary cortisol, countermovement jump (CMJ), and subjective wellness in American college football. METHODS Twenty-three male student athlete American college football players were assessed over 10 weeks: off-season conditioning (3 wk), preseason camp (4 wk), and in season (3 wk). Assessments included a once-weekly FORT and FORD blood sample, urinary cortisol sample, CMJ assessment including flight time, reactive strength index modified and concentric impulse, and a daily subjective wellness questionnaire. Linear mixed models analyzed the effect of a 2 within-subject SD change in the predictor variable on the dependent variable. The effects were interpreted using magnitude-based inference and are presented as standardized effect size (ES) ± 90% confidence intervals. RESULTS Small negative associations were observed between FORT-flight time, FORT-fatigue, FORT-soreness (ES range = -0.30 to -0.48), FORD-sleep (ES = 0.42 ± 0.29), and oxidative stress index soreness (ES = 0.56 ± 0.29). Small positive associations were observed between FORT-cortisol (ES = 0.36 ± 0.35), FORD-flight time, FORD reactive strength index modified and FORD-soreness (0.37-0.41), oxidative stress index concentric impulse (ES = 0.37 ± 0.28), and with soreness-concentric impulse, soreness-flight time, and soreness reactive strength index modified (0.33-0.59). Moderate positive associations were observed between cortisol-concentric impulse and cortisol-sleep (0.57-0.60). CONCLUSION FORT/FORD was associated with CMJ variables and subjective wellness. Greater amounts of subjective soreness were associated with decreased CMJ performance, increased FORT and cortisol, and decreased FORD.
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11
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Davis JK, Wolfe AS, Basham SA, Freese EC, De Chavez PJD. Neuromuscular, Endocrine, and Perceptual Recovery After a Youth American Football Game. J Strength Cond Res 2021; 35:1317-1325. [PMID: 33900264 DOI: 10.1519/jsc.0000000000004011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
ABSTRACT Davis, JK, Wolfe, AS, Basham, SA, Freese, EC, and De Chavez, PJD. Neuromuscular, endocrine, and perceptual recovery after a youth American football game. J Strength Cond Res 35(5): 1317-1325, 2021-American football is a high-intensity intermittent sport consisting of various movements and repeated collisions which highlights the importance of adequate recovery from a game to prepare for the next competition. Therefore, the purpose of this study was to determine the time course of recovery markers after a youth American football game. Thirteen male American football youth players were monitored for 7 days after a single football game. Baseline measures were taken 28 hours pregame for lower-body neuromuscular function by countermovement jumps (CMJs) to determine peak power (PP), jump height (JH), flight time (FT), and takeoff velocity (TOV). Saliva was analyzed for cortisol, testosterone, and C-reactive protein (CRP). Perceptual recovery was assessed by the modified profile of mood states (POMS), perceived recovery status (PRS), and a daily wellness questionnaire. These measures were repeated immediately postgame (30 minutes) and at 20, 44, 68, 92, 116, and 140 hours postgame. Compared with baseline values, there was a significant decrease (p < 0.05) in CMJ PP, JH, and TOV up to 68 hours postgame and FT 44 hours postgame. No significant difference existed among time points for salivary testosterone and CRP. Cortisol levels significantly increased postgame compared with baseline (p < 0.05). Total mood disturbance, assessed by POMS, and daily wellness markers for energy were significantly decreased (p < 0.05), whereas daily wellness markers for soreness were significantly increased (p < 0.05) immediately after the game. Players exhibited a significant decrease in PRS up to 44 hours postgame (p < 0.05), similar to the decrease in neuromuscular function. Neuromuscular function and PRS are impaired for up to 44-68 h postgame.
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Affiliation(s)
| | | | | | - Eric C Freese
- Gatorade Sports Science Institute, Frisco, Texas; and
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12
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Career Longevity and Performance After Shoulder Instability in National Football League Athletes. Arthroscopy 2021; 37:1437-1445. [PMID: 33422614 DOI: 10.1016/j.arthro.2020.12.225] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 12/15/2020] [Accepted: 12/20/2020] [Indexed: 02/02/2023]
Abstract
PURPOSE To investigate the career longevity, game utilization, and performance of National Football League (NFL) athletes after glenohumeral instability events treated operatively versus nonoperatively. METHODS Using public resources, we identified NFL players who sustained a shoulder instability event from September 2000 to February 2019. Players with prior shoulder instability, without NFL experience before injury, or who did not return to play (RTP) after injury were excluded. Demographic information, utilization (games and seasons), and season approximate value (SAV) statistics were recorded 1 year prior to injury and 3 years after RTP. Statistical analysis compared utilization and the SAV after RTP for athletes managed operatively versus nonoperatively. RESULTS We identified 97 NFL players who sustained their first instability event while playing in the NFL, 91 of whom returned to play (93.8%). Quarterbacks were significantly more likely to undergo immediate surgical management compared with players in other positions (P = .023). The final analysis included 58 players managed operatively and 33 managed nonoperatively by the end of the index season. Players treated operatively played in significantly more seasons after RTP during their remaining careers (4.1 ± 2.7 seasons vs 2.8 ± 2.5 seasons, P = .015). There were no differences in games played or started, offensive or defensive snap count percentage, or performance (SAV) before and after injury when compared between cohorts (P > .05). After surgical stabilization, time to RTP (36.62 ± 10.32 weeks vs 5.43 ± 12.33 weeks, P < .05) and time interval before recurrent instability (105.7 ± 100.1 weeks vs 24.7 ± 40.6 weeks, P < .001) were significantly longer than with nonoperative treatment. Additionally, the operative cohort experienced less recurrent instability (27% vs 50%, P = .035). CONCLUSIONS Athletes who RTP in the NFL after a shoulder instability injury do so with a similar workload and performance irrespective of surgical or nonsurgical management. Whereas nonoperative treatment is associated with faster RTP, operative management is associated with fewer recurrent instability events, greater time between recurrent instability events, and greater career longevity. LEVEL OF EVIDENCE Level III, retrospective case-control study.
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Positional Differences in Pre-Season Scrimmage Performance of Division I Collegiate Football Players. SENSORS 2021; 21:s21030769. [PMID: 33498820 PMCID: PMC7865881 DOI: 10.3390/s21030769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 01/18/2021] [Accepted: 01/21/2021] [Indexed: 11/16/2022]
Abstract
This study aimed to describe the physical demands of American football players using novel performance analysis techniques. Heart rate (HR) and accelerometer-based activity levels were observed across two pre-season scrimmages in 23 Division I collegiate football players (age: 19 ± 1 y, height: 1.90 ± 0.06 m, weight: 116.2 ± 19.4 kg). Data were analyzed using a MATLAB program and inter-rater reproducibility assessed using inter-class correlations (ICC). Players were analyzed by side (offense/defense) and position (skill/non-skill). Performance variables assessed in bursts of activity included burst duration, HRmean and HRmax (bpm), and mean activity (vector magnitude units [vmu]). Exercise intensity was categorized as time spent in % HRmax in 5% increments. The burst duration (8.1±3.9 min, ICC = 0.72), HRmean (157 ± 12 bpm, ICC = 0.96) and mean activity (0.30 ± 0.05 vmu, ICC = 0.86) were reproducible. HRmean (p = 0.05) and HRmax (p = 0.001) were greater on defense. Offense spent more time at 65-70% HRmax (p = 0.01), 70-75% HRmax (p = 0.02) while defense spent more time 90-95% HRmax and ≥95% HRmax (p = 0.03). HRmean (p = 0.70) and HRpeak (p = 0.80) were not different between positions across both sides. Skilled players demonstrated greater mean activity (p = 0.02). The sport-specific analysis described HR and activity level in a reproducible manner. Automated methods of assessing HR may be useful in training and game time performance but ultimately provides support to coaching decision making.
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14
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Abstract
Introduction Introduction: very few works offer a practical solution to understand the nutritional requirements of current basketball. This work offers a theoretical-practical proposal. Objectives: to analyze the fatigue produced during a basketball game and offer a practical solution to accelerate recovery through nutrition. Methods: a search of the PubMed bibliographic database for reviews from the last 15 years and original articles from the last 5 years on basketball. Results: type of nutrient and food supplements are essential for a quicker recovery, in addition to their timing and dose. Conclusions: nutrition before, during and after a game or a high-intensity training session plays a fundamental role in the recovery of the basketball player.
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15
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Prevalence and risk indicators of non-carious cervical lesions in male footballers. BMC Oral Health 2020; 20:215. [PMID: 32727438 PMCID: PMC7392645 DOI: 10.1186/s12903-020-01200-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 07/20/2020] [Indexed: 12/02/2022] Open
Abstract
Background Non-carious cervical lesions (NCCLs) have shown a significant incidence and prevalence and have been increasingly associated with people’s lifestyles and youths. This cross-sectional study aimed to determine the prevalence of NCCLs in footballers and to address potential risk indicators. Methods Fourty-three male semi-professional footballers with an average of 27 years old completed a questionnaire and were subjected to intraoral examination in terms of cervical tooth wear, morphological characteristics of NCCLs, tooth sensitivity, occlusal/incisal wear, and malocclusion classification. Also, laboratory assays were performed to determine salivary parameters: flow rate, pH, buffer capacity, level of Ca (calcium), Na (sodium), and K (potassium) ions, and level of cortisol. The data obtained from the questionnaire and intraoral examinations were subjected to Chi-square and Poisson regression models while the data obtained from the laboratory assays were analyzed by using analysis of variance (p < 0.05). Results The prevalence of NCCLs was 39.5%. The participants presented predominantly initial lesions with signs of mechanical stress. The daily training time was found as a significant risk indicator (p = 0.028). The multivariate analysis showed a significant difference in the variables daily training time (p = 0.023), lemon water intake while fasting (p = 0.002), toothpaste type (p = 0.004), tooth sensitivity (p = 0.006); previous orthodontic treatment (p = 0.003), and occlusion type (p = 0.008). All participants presented normal salivary parameters and levels of cortisol. Conclusion The prevalence of NCCLs among footballers was remarkable. The premolars were the most affected teeth and presented symptoms/signs of initial lesions. The daily training time was a dominant risk indicator of NCCLs development. Footballers presented adequate salivary parameters and cortisol levels.
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16
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Hagen J, Himmler A, Clark J, Ramadan J, Stone J, Divine J, Mangine R. Test and Evaluation of Heart Rate Derived Core Temperature Algorithms for Use in NCAA Division I Football Athletes. J Funct Morphol Kinesiol 2020; 5:E46. [PMID: 33467262 PMCID: PMC7739355 DOI: 10.3390/jfmk5030046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 06/26/2020] [Accepted: 07/01/2020] [Indexed: 12/02/2022] Open
Abstract
The purpose of this study was to assess the validity of utilizing heart rate to derive an estimate of core body temperature in American Football athletes. This was evaluated by combining commercially available Zephyr Bioharness devices, which includes an embedded estimated core temperature (ECT) algorithm, and an ingestible radio frequency core temperature pill during the highest heat injury risk timepoint of the season, summer training camp. Results showed a concordance of 0.643 and 78% of all data points fell within +/-1.0 °F. When the athletes were split into Upper (>/=6.0%) and Lower (<6.0%) body composition groups, there was a statistical improvement in accuracy with the Upper Body Fat% reaching 0.834 concordance and 93% of all values falling within +/-1.0 °F of the Gold Standard. Results suggest that heart rate derived core temperature assessments are a viable tool for heat stress monitoring in American football, but more work is required to improve on accuracy based on body composition.
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Affiliation(s)
- Joshua Hagen
- Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26505, USA; (J.H.); (J.R.); (J.S.)
| | - Aaron Himmler
- Department of Athletics, University of Cincinnati, Cincinnati, OH 45221, USA; (A.H.); (J.C.); (J.D.)
| | - Joseph Clark
- Department of Athletics, University of Cincinnati, Cincinnati, OH 45221, USA; (A.H.); (J.C.); (J.D.)
| | - Jad Ramadan
- Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26505, USA; (J.H.); (J.R.); (J.S.)
| | - Jason Stone
- Rockefeller Neuroscience Institute, West Virginia University, Morgantown, WV 26505, USA; (J.H.); (J.R.); (J.S.)
| | - Jon Divine
- Department of Athletics, University of Cincinnati, Cincinnati, OH 45221, USA; (A.H.); (J.C.); (J.D.)
| | - Robert Mangine
- Department of Athletics, University of Cincinnati, Cincinnati, OH 45221, USA; (A.H.); (J.C.); (J.D.)
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Sampson JA, Murray A, Williams S, Sullivan A, Fullagar HHK. Subjective Wellness, Acute: Chronic Workloads, and Injury Risk in College Football. J Strength Cond Res 2019; 33:3367-3373. [DOI: 10.1519/jsc.0000000000003000] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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18
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Appleby BB, Cormack SJ, Newton RU. Reliability of Squat Kinetics in Well-Trained Rugby Players: Implications for Monitoring Training. J Strength Cond Res 2019; 33:2635-2640. [PMID: 31361735 DOI: 10.1519/jsc.0000000000003289] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Appleby, BB, Cormack, SJ, and Newton, RU. Reliability of squat kinetics in well-trained rugby players: implications for monitoring training. J Strength Cond Res 33(10): 2635-2640, 2019-The aim of this study was to determine the within-session reliability in kinetic variables of the squat in well-trained athletes during a typical resistance training protocol. Fifteen subjects completed 2 testing sessions. Session 1 was establishment of 1 repetition maximum (1RM) squat, and session 2 involved 2 sets of 2 maximal effort repetitions of the squat at 70, 80, and 90% of 1RM with 3D motion analysis and ground reaction force (GRF) measurement using 2 in-ground triaxial force plates. Reliability was calculated using typical error ± 90% confidence limits, expressed as the coefficient of variation and intraclass correlation coefficient. The smallest worthwhile change (SWC%), calculated as 0.2 × between-subject SD, was used to determine the smallest important change in performance. Peak GRF and average GRF were found to have acceptable measures of reliability with the combined left and right leg average GRF capable of detecting the SWC. Independent limb contributions were reliable (left and right, or dominant and nondominant). Reliable kinetics can be obtained in back squat performance typical of a resistance training session in well-trained athletes. This suggests that coaches integrating force plate technology within training sessions may effectively capture between 1 and 6 training sets among several athletes, facilitating analysis and intervention on larger data sets.
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Affiliation(s)
- Brendyn B Appleby
- School of Medical and Health Sciences, Edith Cowan University, Perth, Australia.,Hockey Australia, High Performance Unit, Perth, Australia
| | - Stuart J Cormack
- School of Behavioural and Health Sciences, Australian Catholic University, Melbourne, Australia
| | - Robert U Newton
- School of Medical and Health Sciences, Edith Cowan University, Perth, Australia.,School of Human Movement and Nutrition Sciences, The University of Queensland, Brisbane, Australia
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The Effect of Block Versus Daily Undulating Periodization on Strength and Performance in Adolescent Football Players. Int J Sports Physiol Perform 2019; 14:814–821. [PMID: 30569761 DOI: 10.1123/ijspp.2018-0609] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Purpose: Muscle mass, strength, and power are important factors for performance. To improve these characteristics, periodized resistance training is used. However, there is no consensus regarding the most effective periodization model. Therefore, the purpose of this study was to compare the effects of block (BLOCK) vs daily undulating periodization (DUP) on body composition, hypertrophy, strength, performance, and power in adolescent American football players. Methods: A total of 47 subjects participated in this study (mean [SD] age = 17 [0.8] y, strength training experience = 0.93 [0.99] y). Premeasurements and postmeasurements consisted of body mass (BM); fat mass; relative fat mass; fat-free mass (FFM); muscle mass (MM); muscle thickness of the vastus lateralis (VL), rectus femoris (RF), and triceps brachii (TB); 1-repetition-maximum back squat (BS) and bench press (BP); countermovement jump (CMJ); estimated peak power (Wpeak) from vertical jump performance; medicine-ball put (MBP); and 40-yd sprint. Subjects were randomly assigned in either the BLOCK or DUP group prior to the 12-wk intervention period consisting of 3 full-body sessions per week. Results: Both groups displayed significantly higher BM (P < .001), FFM (P < .001), MM (P < .001), RF (P < .001), VL (P < .001), TB (P < .001), BS (P < .001), BP (P < .001), CMJ (P < .001), Wpeak (P < .001), and MBP (P < .001) and significantly lower sprint times (P < .001) after 12 wk of resistance training, with no difference between groups. Conclusions: Resistance training was effective to increase muscle mass, strength, power, and performance in adolescent athletes. BLOCK and DUP affect anthropometric measures and physical performance equally.
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Fullagar HH, Sampson JA, Delaney J, McKay B, Murray A. The relationship between objective measures of sleep and training load across different phases of the season in American collegiate football players. SCI MED FOOTBALL 2019. [DOI: 10.1080/24733938.2019.1618491] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Hugh H.K Fullagar
- Faculty of Health, University of Technology Sydney, Sydney, Australia
| | - John A. Sampson
- Centre for Human and Applied Physiology, University of Wollongong, Wollongong, Australia
| | - Jace Delaney
- Athletics, University of Oregon, Eugene, OR, USA
| | - Ben McKay
- Centre for Human and Applied Physiology, University of Wollongong, Wollongong, Australia
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Fullagar HHK, Delaney J, Duffield R, Murray A. Factors influencing home advantage in American collegiate football. SCI MED FOOTBALL 2018. [DOI: 10.1080/24733938.2018.1524581] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Hugh H. K. Fullagar
- Faculty of Health, UTS Sport and Exercise Science, University of Technology Sydney, Moore Park, Australia
| | - Jace Delaney
- Department of Athletics, University of Oregon, Eugene, USA
| | - Rob Duffield
- Faculty of Health, UTS Sport and Exercise Science, University of Technology Sydney, Moore Park, Australia
| | - Andrew Murray
- Department of Athletics, University of Oregon, Eugene, USA
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Abstract
In the modern era, rehabilitation after sports injury has become a domain for specialists, and its evolution has necessarily brought together the sports physiotherapist, the sports physician, and the orthopedic surgeon. The changing profile of sports related injury, as well as limited availability of facilities for rehabilitation in many areas of India, is a matter of concern. Elite sportspersons have some protection, but the average athlete is often left to fend for himself. Key factors in successful sports injury rehabilitation protocols are the application of modern rehabilitation protocols under appropriate supervision, appropriate and well timed surgical interventions, and judicious and need based use of pharmaceutical agents. Modern rehabilitation protocols emphasize teamwork and proper rehabilitation planning, and the rehabilitation team has to be lead by a trained sports physiotherapist, with an understanding of the protocols and interventions required at various stages. Injury specific rehabilitation protocols are being practiced worldwide but need to be introduced according to the nature of the sport as well as available facilities. Even in India, sports physicians are increasingly joining specialist rehabilitation teams, and they can help with medication, nutritional supplements, and specialized tests that could improve injury understanding. Inputs from surgeons are mandatory if surgical interventions have been performed. What is often missing in the underdeveloped world is psychological support and a clear understanding by the athlete of his/her rehabilitation protocols. World over, the primary aims are safe return to sports and minimizing reinjury on return to sport; this involves rehabilitation in stages, and current methodology clearly demarcates acute and chronic phases of injury. Close coordination with trainers and coaches is mandatory, and all need to understand that the reconditioning phase is crucial; skill assessment before progression has now become a specialized domain and needs to be introduced at all levels of the sport. A key factor in all sports injury rehabilitation protocols is injury prevention; this involves data maintenance by teams or trainers, which is still not fully developed in the Indian context. The injury and subsequent problems need to be comprehended both by athletes and their coaches. The current review is an attempt to clarify some of the issues that are important and routinely used world over, with the aim to improving rehabilitation after sports even in the underdeveloped world.
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Affiliation(s)
| | - Sidak Dhilllon
- Department of Sports Medicine, Sri Ramachandra Medical University, Chennai, Tamil Nadu, India
| | - Mandeep S Dhillon
- Department of Orthopaedic Surgery, Physical Medicine and Rehabilitation Medicine, Sports Injury Clinic, PGIMER, Chandigarh, India,Address for correspondence: Prof. Mandeep S Dhillon, 1027, Sector 24 B, Chandigarh - 160 023, India. E-mail:
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