Applied Sports Science newsletter – September 26, 2016

… It is certainly startling to tot up the numbers of games Kompany has missed, the repetitive nature of his injuries and the seemingly endless churn of rehab, comebacks, breakdowns and sapping disappointment, and not be weighed down by the suspicion that a club with City’s ambitions will eventually decide there is no way back. Kompany’s 14 different calf injuries have accounted for 333 days of absence during his time in Manchester. Among the other ailments, there have been six spells of absenteeism with hamstring issues, four with groin problems and three with both knee and thigh injuries. Since August 2014, Kompany has missed exactly half of City’s first-team assignments. It is a cruel thing to say but Roberto Mancini had the wrong man when Micah Richards was hurt in one game and the Italian, showing all the tact for which he was renowned, tapped the glass in front of him. “Swarovski,” he said – meaning the player was made of crystal.

Pep Guardiola is not so bruising in his public statements but it would be easy to understand if Kompany is filled with insecurity given the speed at which City’s new manager has moved Joe Hart off the premises, ostracised Yaya Touré and made it clear he is unmoved by what has gone before. Guardiola did not even inform Touré – a mandatory pick if you were asking this correspondent for the greatest ever City XI – he was not in the club’s Champions League squad. He has asked for an apology from the player’s agent but would it really make a jot of difference if the opinionated, arrogant, selfish, gaudy, trash-talking Dimitri Seluk – and these are just his good points – sent him flowers every day for the next month? The truth is Guardiola has zero intentions of playing Touré anyway. He bends for nobody. And if Kompany isn’t worried, he probably should be.

… On April 28, the Cowboys stunned the NFL when they made Elliott the No. 4 draft pick. Even Elliott’s mom, Dawn, was shocked. She’d been surprised to be invited to the draft in Chicago and the implication that her son could be taken in the first round. Teams do not invest in running backs with a No. 4 selection anymore. … And why not? Put Elliott, a bruising 225-pound workhorse who can block and run all day, behind arguably the NFL’s best offensive line and good things are bound to happen. He could take pressure off quarterback Tony Romo (or Dak Prescott, now that Romo is out with a compression fracture in his spine) and help control the time of possession, which would aid the defense. On the field, Elliott has an awareness and a skill set that make him one of the most promising running backs since Adrian Peterson. Off it, he has shown signs of being less of a sure thing.

… “The last two years I think have taught all of us within the organization that, everybody says it’s a marathon, but it really is,” Bob Myers said on Thursday. “We realized last year that mile 24 — I haven’t run a marathon, maybe some of you have — but they say that once you hit mile 20 or 21, the last five miles are the worst. And I think we learned last year that you gotta have something at mile 24, gotta have something at mile 25. I think we all have to take, us and the organization, have to take the approach that it’s a long road. We gotta have some juice.”

The importance of agility in basketball is well known, but there is an evident lack of studies examining basketball-specific agility performances in high-level players. The aim of this study was to determine the reliability and discriminative validity of one standard agility-test (T-TEST), and four newly developed basketball-specific agility-tests, in defining playing-positions and performance-levels in basketball. The study comprised 110 high-level male basketball players (height: 194.92+/-8.09 cm; body mass: 89.33+/-10.91 kg; 21.58+/-3.92 years of age). The variables included playing-position (Guard, Forward, Center), performance-level (first-division vs. second-division), anthropometrics (body-height, body-mass, and percentage of body-fat), T-TEST, non-planned basketball-agility-test performed on dominant- (BBAGILdom) and non-dominant side (BBAGILnond) and a pre-planned (change-of-direction-speed) basketball-agility-test performed on dominant- (BBCODSdom) and non-dominant side (BBCODSnond).

The reliability of agility-tests was high (ICC of 0.81-0.95). Forwards were most successful in the T-TEST (F test: 13.57; p = 0.01), Guards outperformed Centers in BBCODSdom, BBCODSndom, BBAGILdom, and BBAGILnond (F test: 5.06, p = 0.01; 6.57, 0.01; 6.26, 0.01; 3.37, 0.04, respectively). First-division Guards achieved better results than second-division Guards in BBCODSdom (t-value: 2.55; p = 0.02; moderate effect-size-differences (ESD)), BBAGILdom and BBAGILnond (t-value: 3.04, and 3.06, respectively; both p = 0.01 and moderate ESD). First-division Centers outperformed second-division Centers in BBAGILdom (t-value: 2.50; p = 0.02; moderate ESD).

The developed basketball-specific agility tests are applicable when defining position-specific agility. Both pre-planned and non-planned agility are important qualities in differentiating between Guards of two performance-levels. The results confirmed the importance of testing basketball-specific non-planned agility when evaluating the performance level of Centers.

Background The architectural and morphological adaptations of the hamstrings in response to training with different exercises have not been explored.

Purpose To evaluate changes in biceps femoris long head (BFLH) fascicle length and hamstring muscle size following 10-weeks of Nordic hamstring exercise (NHE) or hip extension (HE) training.

Methods 30 recreationally active male athletes (age, 22.0±3.6?years; height, 180.4±7?cm; weight, 80.8±11.1?kg) were allocated to 1 of 3 groups: (1) HE training (n=10), NHE training (n=10), or no training (control, CON) (n=10). BFLH fascicle length was assessed before, during (Week 5) and after the intervention with a two-dimensional ultrasound. Hamstring muscle size was determined before and after training via MRI.

Results Compared with baseline, BFLH fascicles were lengthened in the NHE and HE groups at mid-training (d=1.12–1.39, p<0.001) and post-training (d=1.77–2.17, p<0.001) and these changes did not differ significantly between exercises (d=0.49–0.80, p=0.279–0.976). BFLH volume increased more for the HE than the NHE (d=1.03, p=0.037) and CON (d=2.24, p<0.001) groups. Compared with the CON group, both exercises induced significant increases in semitendinosus volume (d=2.16–2.50, ?0.002) and these increases were not significantly different (d=0.69, p=0.239).

Conclusion NHE and HE training both stimulate significant increases in BFLH fascicle length; however, HE training may be more effective for promoting hypertrophy in the BFLH.

September 29, 2016

Our symposium will launch the Exercise and Sport Science Institute (ESSI), a unique research initiative managed by the University of Michigan Office of Research and Athletic Department. It will include a full day of talks and panel discussions related to sport technology R&D, data science and analytics, and optimal human performance. The symposium will include a mix of both academic and industry speakers.

With a record haul of medals at the Olympics, we take a look at how the Great Britain Triathlon Team have continued to try and push the boundaries of scientific understanding in the pursuit of medals, through strategic relationships with World-Class facilities and Sports Scientists.

… Over the past nine years Alianza de Futbol Hispano has staged annual tryouts and youth tournaments in a dozen U.S. cities, drawing more than 80,000 players – and dozens of scouts from all over the Americas.

More than 60 players have signed professional contracts after being discovered at an Alianza showcase, most with teams in Mexico’s Liga MX. Last year alone 33 of Alianza’s national finalists fielded a combined 116 invitations from 14 Liga MX teams.

And more than 25 players have been recruited for age-group national teams in the U.S., Mexico, Guatemala and El Salvador, making Alianza one of the largest and most successful soccer scouting programs in the region.

The Philadelphia 76ers unveiled their new Camden training complex Friday morning, with team Managing Owner Josh Harris calling it “the best in all professional sports.”

The 125,000-square-foot training complex along Camden’s waterfront is the largest in the National Basketball Association.

How does the brain represent visual information from the outside world? Here, we approach this question with a deep convolutional neural network that mimics neuronal circuitry and coding, and learns to solve computer vision tasks. Using this network as a computational model of the visual cor-tex, we develop novel encoding and decoding mod-els to describe the bi-directional relationships be-tween visual input and cortical activity measured with functional magnetic resonance imaging. Test-ing these models with imaging data from humans watching natural movies, we show that the encod-ing model can predict cortical responses and re-trieve visual representations at individual brain lo-cations, and that the decoding model can decipher the measured cortical activity to reconstruct the visual and semantic experiences. Both the encod-ing and decoding models utilize cortical representa-tions of hierarchical, invariant, and nonlinear visual features. Being self-contained, efficient, and gener-alizable, these models constitute a computational workbench for high-throughput investigation of all stages of visual processing. We also anticipate that the general strategy for neural encoding and decod-ing via deep-learning models will be applicable to other sensory or cognitive experiences, e.g. speech, imagery, memories and dreams.

Background: Soccer has one of the highest rates of ankle injury in sports for both males and females. Several injury prevention programs have been developed to address this concern. The purposes of this study were to conduct a meta-analysis of ankle injury prevention programs for soccer players, assess the heterogeneity among the studies, and evaluate the reported effectiveness of the prevention programs.

Methods: A systematic search of the literature was conducted in PubMed (MEDLINE), Embase, CINAHL (Cumulative Index to Nursing and Allied Health), and the Cochrane Central Register of Controlled Trials (CENTRAL) database. Studies were limited to clinical investigations of injury prevention programs specific to the ankle in soccer players. Title, abstract, and full-text review were utilized to identify articles that met the inclusion criteria. The Cochrane Q test and I2 index were independently used to assess heterogeneity among the studies. Sensitivity analyses were performed to assess heterogeneity. The pooled risk difference was calculated by random-effects models with use of the DerSimonian-Laird method. Publication bias was assessed with a funnel plot and Egger weighted regression technique.

Results: Ten studies met the inclusion criteria as randomized controlled trials. A total of 4,121 female and male soccer athletes were analyzed for ankle injuries. Significant heterogeneity was found among studies of ankle injury prevention (p = 0.002), with an I2 index of 65.2%. For studies of ankle injury prevention programs, the risk ratio was 0.60 (95% confidence interval, 0.40 to 0.92) and a significant reduction in the risk of ankle injury was found in the prevention group (p = 0.002). No evidence of publication bias was found among the included studies.

Conclusions: This meta-analysis of studies regarding ankle injury prevention programs identified a significant reduction in the risk of ankle injury. Future high-quality research designs with a low risk of bias are necessary to further evaluate the effectiveness of specific exercises and the optimal timing and age at intervention for the prevention of ankle injuries in the athletic soccer player. [full text]

… “Historically, sports provided understandable examples of basic statistical concepts,” said Rebecca Nugent, teaching professor and director of undergraduate studies in Carnegie Mellon University’s Department of Statistics. “In recent years, however, the demand for complex statistical analyses in sports has exploded, with teams and leagues collecting massive amounts of data on every player in every game. It’s a whole new ballgame—pun intended!”

Earlier this month, undergraduate students in the Dietrich College of Humanities and Social Sciences’ statistics major and members of the Tartan Sports Analytics Club (TSAC) explored how statistics and sports go hand in hand at a Pittsburgh Pirates game.

“The challenges facing analysts in today’s professional sports world are extremely similar to the types of problems that our statistics undergraduates work on every day: analyzing large, complex datasets with modern statistical methodology,” noted Sam Ventura, a visiting assistant professor in the statistics department and faculty adviser of TSAC. Ventura also works as an analytics consultant for the Pittsburgh Penguins.

… In an ideal world, analysts would walk into clubs with the red carpet rolled out, with a supportive front office staff, a receptive, communicative coach, and players who are eager to get help wherever they can.

The reality is that there are longstanding, entrenched club cultures, particularly in football, and analysts often find themselves navigating a complex world of superstitions and customs they are not privy to. As Gage writes, “The problem is deep rooted and fundamentally a social issue. The unfortunate fact is that the majority of footballers and therefore future head coaches are not mathematicians, scientists or economists growing up. From ages 7-35 they eat, sleep and live football/soccer.”

Up until now, many have taken a highly deferential approach by avoiding stepping on any toes, listening more than speaking at meetings, doing their work in a quiet corner. After all, the manager/coach is still king, and work in close tandem with the most valuable assets in the club—the players. While it seems exceedingly stupid, at least to me, to hire an analyst when you have a manager who thinks statheads are full of crap, the fact is this is still the case.

… All other variables the same, the closer the shot, the easier it is to make. Prior to the 3-point line and even in the first few years of its existence, the best shots (by far) were those near the hoop. As a result, NBA defenses protected that region at all costs. Teams collapsed with help defense to the best of their ability (under the old illegal defense rules). In those days, forcing a kick out on penetration was a win for the defense.

Today, the best defenses are doing the opposite. They are sending minimal help on the drive. In particular, teams are not leaving the corners open, and they are terrified to leave an elite shooter (e.g. Steph Curry, Kyle Korver or J.J. Redick) alone anywhere behind the arc.

To assess defensive strategy on penetration we’ll use measurements of offensive and defensive stretch, which were introduced in Basketball Analytics: Spatial Tracking.

New research from the Sport and Recreation Alliance (SRA) shows that 60% of sports clubs recruit new coaches from within their club. As they suggest

‘This shows the relative lack of recruitment from wider society which partially explains the shortage of diversity within sports volunteers.’

Our research would agree with the SRA that recruitment practices can restrict diversity in coaching.