… “Every player here, every staff member, I think we all want to win the tournament,” said [Aaron] Herrera. “I think that’s the goal going forward. But we know that being here a long time, we’ve got to look forward to just the next step, and just one step at a time, and right now it’s Costa Rica on March 18, so I think that that’s where all our focus and all our energy is right now.”
The lengthy pre-tournament camp is both a response to MLS’s delayed start to the 2020 season and an effort to help players adapt to the high altitude and warm spring weather of the Mexican Altiplano, while also helping to build team spirit. It’s also given Kreis and his staff a chance to gather final firsthand observations before trimming their squad.
There’s friendship among the group, but also keen competition. Coaching staffs are mandated to submit their final rosters 10 days before their team’s first match, so Kreis has probably already made his decisions. Concacaf is slated to officially release those lists to the public on Thursday.
Chicago Tribune, Associated Press, Howard Fendrich from
…
“There would be times where I would run out in the fifth, sixth, seventh inning and feel like I hit a brick wall. There were times last year where I would come out of the bullpen and be like: ‘God, did I pitch the game already?’” the 37-year-old Lester, who is now with the Washington Nationals, said Wednesday during a video conference from spring training in West Palm Beach, Florida. “Just thinking that maybe I needed to do a little extra in the weight room. Maybe I needed to run a bit more. Maybe I needed to do 20 extra minutes on cardio or whatever. When in actuality, this thing was slowing me down.”
“This thing” turned out to be hyperparathyroidism, which can affect the amount of calcium levels in the bloodstream and lead to someone tiring easily. So last week, Lester left camp to have what he called very minor surgery to remove one of his parathyroid glands — a scar now runs horizontally at the base of the front of his neck — and he says he already senses a difference in his energy levels.
The study aimed to identify the effects of situational (match location, match outcome and strength of team/opponent team) and environmental (ambient temperature, relative humidity, WBGT, ground and weather condition) factors on the physical and technical activity of elite football on individual playing positions. Physical and technical activity were collected from 779 football players competing in the German Bundesliga during 5 domestic seasons, from 2014/2015 to 2018/2019, totalling 1530 matches. The data on players’ physical and technical activity was taken from the IMPIRE AG system. Based on the available data, 11 variables were selected to quantify the match activity profiles of players. The results showed that situational variables had major effects on the technical performance (especially number of passes performed) but minor effects on physical performance. In turn, among the analysed environmental factors, temperature is the most sensitive, which affects the Total Distance and Sprint Efforts of players in all five positions. This investigation demonstrated that, given that passing is a key technical activity in modern football, players and training staff should be particularly aware that passing maybe affected by situational variables. Professional players are able to react and adapt to various environmental conditions, modifying physical activity depending on the needs in German Bundesliga. These results could help coaches and analysts to better understand the influences of situational and environmental variables on individual playing positions during the evaluation of players’ physical and technical performance.
Football is evolving in many ways including the technical and physical demands as well as the scientific research underpinning and providing many recommendations to practitioners on how to optimise performance of players and by default, team performance. Evolution is a natural process and necessary to grow and develop. Research into football is no different. Researchers are by nature, curious and inquisitive and trying to push the boundaries of knowledge, however, researchers are also humans and humans are open to making errors. The important point is that researchers learn from both their own and others’ mistakes, evolving, growing and developing in response. By doing so will maximise the impact that can research can have on the field. With this commentary, i discuss lessons that can be learned from some common mistakes I and others have made in football (and sports) related research and some insights into to evolve our profession for the better. [fulltext]
Despite various solutions proposed to solve the relative age effect (RAE), it is still a major problem confounding talent identification and selection processes. In the first phase, we sampled 302 under 7–21 academy soccer players from two Belgian professional soccer clubs to explore the potential of a new approach to solve the inequalities resulting from relative age- and maturity-related bias. This approach allocates players into four discrete quartile groups based on the midway point of their chronological and estimated developmental (ED) birth dates (calculated using the growth curves for stature of Belgian youth). With the use of chi square analyses, a RAE was found (p < 0.01) for the overall sample (Q1 = 41.4% vs. Q4 = 14.9%) that completely disappeared after reallocation (Q1 = 26.5%; Q2 = 21.9%; Q3 = 27.5%; Q4 = 24.2%). According to the new allocation method, the stature difference was reduced, on average, by 11.6 cm (from 24.0 ± 9.9 to 12.4 ± 3.4 cm, d = 1.57). Body mass difference between the two methods was 1.9 kg (20.1 ± 11.3–18.2 ± 13.1 kg, respectively, d = 0.15). The new method created a maximum chronological age difference of 1.9 vs. 0.8 years for the current method. With the use of this method, 47% of the players would be reallocated. Twenty-three percent would be moved up one age category, and 21% would be moved down. In the second phase, we also examined 80 UK academy soccer players to explore if reallocating players reduces the within-playing group variation of somatic and physical fitness characteristics. The percentage coefficient of variation (%CV) was reduced (0.2–10.1%) in 15 out of 20 metrics across U11–U16 age categories, with the U13 age category demonstrating the largest reductions (0.9–10.1%) in CV. The U12 and U13 age categories and associated reallocation groupings showed trivial to small (ES = 0.0–0.5) between-method differences and trivial to moderate (ES = 0.0–1.1) differences within the U14–U16 age categories. A reduction in RAE may lead to fewer dropouts and thus a larger player pool, which benefits, in turn, talent identification, selection, and development. [full text]
Footfalls & Heartbeats, the Nottingham, UK-based developer of smart fabrics, has secured funding from the European Commission through the European Smart Textile Accelerator programme (SmartX).
In a collaborative project, it will now focus on developing KiTT, its motion tracking knee sleeve which sits over the joint directly and provides advanced data and insight into its condition.
North Carolina State University, NC State News from
North Carolina State University engineers continue to improve the efficiency of a flexible device worn on the wrist that harvests heat energy from the human body to monitor health.
In a paper published in npj Flexible Electronics, the NC State researchers report significant enhancements in preventing heat leakage in the flexible body heat harvester they first reported in 2017 and updated in 2020. The harvesters use heat energy from the human body to power wearable technologies – think of smart watches that measure your heart rate, blood oxygen, glucose and other health parameters – that never need to have their batteries recharged. The technology relies on the same principles governing rigid thermoelectric harvesters that convert heat to electrical energy.
Flexible harvesters that conform to the human body are highly desired for use with wearable technologies. Mehmet Ozturk, an NC State professor of electrical and computer engineering and the corresponding author of the paper, mentioned superior skin contact with flexible devices, as well as the ergonomic and comfort considerations to the device wearer, as the core reasons behind building flexible thermoelectric generators, or TEGs.
University of California-San Diego, UC San Diego News Center from
Nanoengineers at the University of California San Diego have developed a “wearable microgrid” that harvests and stores energy from the human body to power small electronics. It consists of three main parts: sweat-powered biofuel cells, motion-powered devices called triboelectric generators, and energy-storing supercapacitors. All parts are flexible, washable and can be screen printed onto clothing.
The technology, reported in a paper published Mar. 9 in Nature Communications, draws inspiration from community microgrids.
“We’re applying the concept of the microgrid to create wearable systems that are powered sustainably, reliably and independently,” said co-first author Lu Yin, a nanoengineering Ph.D. student at the UC San Diego Jacobs School of Engineering.
Younger patients are at increased risk for anterior cruciate ligament (ACL) graft rupture and contralateral injury after ACL reconstruction (ACLR). Increasing the amount of time between surgery and the resumption of competitive sport may reduce this risk. Purpose:
To determine the rates of graft rupture and injury to the contralateral native ACL at 3- to 5-year follow-up in younger patients who were advised to delay a return to competitive sport until 12 months after surgery and compare this with a nondelayed cohort. Study Design:
Cohort study; Level of evidence, 3. Methods:
The primary study cohort consisted of 142 eligible patients aged <20 years when they underwent their first primary ACLR. All were informed about the risk of further injury and advised not to return to competitive sport before 12 months postoperatively. Return-to-sport status and the number of subsequent ACL injuries (graft rupture or a contralateral injury to the native ACL) were determined at 3- to 5-year follow-up and compared with a historic cohort of 299 patients with ACLR who were not advised to delay their return to sport for a set period. The cohorts were then combined, and injury rates were compared between those who returned to sport before and after 12 months postoperatively.
Results:
The follow-up rate was 91% (129/142). In the delayed cohort, 63% returned to competitive sport after 12 months (mean, 14 months). Few patients (n = 10) returned before 9 months. In the delayed group, 33% had a subsequent ACL injury; this was not significantly different when compared with the nondelayed group (31% rate), in which a majority (58%) returned to competitive sport before 12 months. Subsequent ACL injury rates were also similar when compared between patients who returned before and after 12 months postoperatively (33% vs 32%, respectively). Conclusion:
At midterm follow-up, the overall rates of subsequent ACL injury were high, even for patients who delayed their return until 12 months after surgery. More research is required to identify strategies to reduce the high reinjury rate in younger athletes.
A new study of more than 2,000 volleyball player injuries has quantified the extent to which in-season injuries can affect the quality of life (QOL) of the athlete.
The study, “Impact of in-season injury on quality of life and sleep duration in female youth volleyball athletes: a prospective study of 2,073 players,” published online on February 24, 2020 in the British Journal of Sports Medicine, evaluated the influence of injury on quality of life and sleep in female high school volleyball athletes.
… High school sports amidst a pandemic has been an active combination since August. There was doubt and debate about whether sports could even happen during COVID-19. Football teams across the Dallas area, for example, dealt with pauses due to quarantine and over 100 canceled football games throughout the year, but ultimately state championships in December and January concluded a season that was as unique as it was challenging.
There’s relief in conclusion, but for athletic trainers that relief never came. That’s because fall sports turned to winter sports, which have overlapped with the start of spring sports. It’s been nonstop for trainers.
The University of Nevada athletics department has launched the Alpha Fund campaign to help support the nutrition and performance program specifically for women student-athletes.
A meal distribution plan started in early 2021 with female student-athletes receiving NCAA-allowed incidental meals at breakfast up to three days per week.
The initial goal of the program is $100,000 but the annual cost to meet the nutritional needs of women’s athletics programs at Nevada is around $200,000 annually, which would provide one full meal using fresh ingredients each day for the 200+ women student-athletes, via both campus dining options or local community restaurant delivery.
In order to make comparisons of competitive balance across sports leagues, we need to take into account how different season lengths influence observed measures of balance. We develop the first measures of competitive balance that are invariant to season length. The most commonly used measure, the ASD/ISD or Noll-Scully ratio,is biased. It artificially inflates the imbalance for leagues with long seasons (e.g., MLB) compared to those with short seasons (e.g., NFL). We provide a general model of competition that leads to unbiased variance estimates. The result is a new ordering across leagues: the NFL goes from having the most balance to being tied for the least, while MLB becomes the sport with the most balance. Our model also provides insight into competitive balance at the game level. We shift attention from team-level to game-level measures as these are more directly related to the predictability of a representative contest. Finally, we measure competitive balance at the season level. We do so bylooking at the predictability of the final rankings as seen from the start of the season. Here the NBA stands out for having the most predictable results and hence the lowest full-season competitive balance.
… Research has analysed the differences between the English Premier League (EPL) and the Spanish Liga (La Liga) with three game variables: the type of ball recovery, the location of such recovery and the duration of the possession and how all these affect the result of the possession. For that, they analysed 4971 possessions in 10 matches of the EPL and La Liga during the 2017-2018 season. These matches included 18 of the 20 teams of the EPL and 17 of the 20 teams that played in La Liga. The location of the ball at the moment of recovery was obtained by dividing the football field in 12 areas: left, centre and right aisles for defensive, pre-defensive, pre-attack, and attack zones. Ball recovery was classified in 5 categories: interception, tackle, goalkeeper’s save, set piece and loss. The duration of the possession was organised in 3 categories: less than 5 seconds, between 5 and 12 seconds and more than 12 seconds. Finally, the result of the possession was classified in 15 categories (goal, shot at goal, shot outside, blocked shot, free kick, penalty kick, corner kick, offside, loss of the ball due to bad control or pass, clearance, foul, interception, tackle, clearance by the defence, goalkeeper catches the ball).