Applied Sports Science newsletter – January 22, 2018

… [Megan Campbell] jumped at the chance to join the Women’s Super League (WSL) club in February 2016 and was eager to impress straight away, but a series of setbacks would rule her out for over a year.

The most serious damage required ankle reconstruction surgery and eight months of rehabilitation. Meanwhile, Campbell’s City team-mates claimed a domestic double that season as she watched on from the sidelines.

Countless hours in the gym were required and the full-back admits some days were more frustrating than others.

First, let’s dispense with the folklore surrounding Keelan Cole when he first arrived at Kentucky Wesleyan College as a freshman in 2012: he was not 135 pounds.

“I’d say he was 140,” coach Brent Holsclaw said.

See, these are the tall tales that make Cole’s sudden star turn in the NFL playoffs seem so outrageous. When you strip away the hyperbole, it’s perfectly plausible that an undrafted free agent who was a glorified walk-on at a lower-echelon NCAA Division II school would catch the biggest pass in Jacksonville’s divisional playoff upset of Pittsburgh last weekend. Really, what’s so surprising about a kid who started a total of three games in high school becoming the stealth deep threat whose 45-yard reception helped beat the Steelers?

OK, everything.

The Warriors are looking as strong as ever this season but there is real concern about the long-term health of one of the NBA’s finest players

… Ertz (née Johnston) owes at least part of that success to her decision to follow Zach from Northern California to Philadelphia. The couple, who married last year, settled less than 30 minutes from Carli Lloyd’s New Jersey home. Lloyd invited Ertz, then just beginning to break into the national team, to work with her and James Galanis, her unconventional coach.

That would never have happened had her then-boyfriend signed with the Green Bay Packers.

Four-time USAV Male Indoor Player of the Year and 2016 Olympic Bronze medalist, Matt Anderson, began his ‘Path to the Podium’ with a High Performance tryout!

Understanding the patterns and processes of human cooperation is of central scientific importance. Networks can promote cooperation when their existing or emergent topology allows conditional cooperators in the network to isolate themselves from exploitation by noncooperators. We do not know from prior work whether the emergent structures that promote cooperation are driven by reputation or can emerge purely via dynamics, i.e., the severing of ties to noncooperators and the formation of new ties irrespective of reputational information. Here we demonstrate, experimentally, that dynamic networks yield very high rates of cooperation even without reputational knowledge. Further, we identify realistic conditions under which static networks (where ties cannot be altered) yield cooperation rates as high as those in dynamic networks.

Purpose:

The aim of this study was to quantify and predict relationships between rating of perceived exertion (RPE) and GPS training-load (TL) variables in professional Australian football (AF) players using group and individualized modeling approaches.
Methods:

TL data (GPS and RPE) for 41 professional AF players were obtained over a period of 27 wk. A total of 2711 training observations were analyzed with a total of 66 ± 13 sessions/player (range 39–89). Separate generalized estimating equations (GEEs) and artificial-neural-network analyses (ANNs) were conducted to determine the ability to predict RPE from TL variables (ie, session distance, high-speed running [HSR], HSR %, m/min) on a group and individual basis.
Results:

Prediction error for the individualized ANN (root-mean-square error [RMSE] 1.24 ± 0.41) was lower than the group ANN (RMSE 1.42 ± 0.44), individualized GEE (RMSE 1.58 ± 0.41), and group GEE (RMSE 1.85 ± 0.49). Both the GEE and ANN models determined session distance as the most important predictor of RPE. Furthermore, importance plots generated from the ANN revealed session distance as most predictive of RPE in 36 of the 41 players, whereas HSR was predictive of RPE in just 3 players and m/min was predictive of RPE in just 2 players.
Conclusions:

This study demonstrates that machine learning approaches may outperform more traditional methodologies with respect to predicting athlete responses to TL. These approaches enable further individualization of load monitoring, leading to more accurate training prescription and evaluation.

The relationship between recovery and fatigue and its impact on performance has attracted the interest of sports science for many years. An adequate balance between stress (training and competition load, other life demands) and recovery is essential for athletes to achieve continuous high-level performance. Research has focused on the examination of physiological and psychological recovery strategies to compensate external and internal training and competition loads. A systematic monitoring of recovery and the subsequent implementation of recovery routines aims at maximizing performance and preventing negative developments such as underrecovery, non-functional overreaching, the overtraining syndrome, injuries, or illnesses. Due to the inter- and intra-individual variability of responses to training, competition, and recovery strategies, a diverse set of expertise is required to address the multifaceted phenomena of recovery, performance and their interactions to transfer knowledge from sports science to sports practice. For this purpose, a symposium on Recovery and Performance was organized at the Technical University Munich Science and Study Center Raitenhaslach (Germany) in September 2016. Various international experts from many disciplines and research areas gathered to discuss and share their knowledge of recovery for performance enhancement in a variety of settings. The results of this meeting are outlined in this consensus statement that provides central definitions, theoretical frameworks, as well as practical implications as a synopsis of the current knowledge of recovery and performance. While our understanding of the complex relationship between recovery and performance has significantly increased through research, we also elaborate some important issues for future investigations.

… “They had four disks to load into their computer and they’d put in their injury information and their fitness testing data and use it to write training programmes.

“They’d then do a back up of their testing data and send it back to us. That was the first data management platform, back in the ’90s.”

Fast-forward 20 years, and Riddle was in another country, another continent, working to create a similar data management platform with Microsoft.

This time Real Madrid were wanting to get into the sports science game, and Riddle was uniquely placed to help out.

The Y Balance Test (YBT) is one of the most commonly utilised clinical dynamic balance assessments. Research has demonstrated the utility of the YBT in identifying balance deficits in individuals following lower limb injury. However, quantifying dynamic balance based on reach distances alone fails to provide potentially important information related to the quality of movement control and choice of movement strategy during the reaching action. The addition of an inertial sensor to capture more detailed motion data may allow for the inexpensive, accessible quantification of dynamic balance control during the YBT reach excursions. As such, the aim of this study was to compare baseline and fatigued dynamic balance control, using reach distances and 95EV (95% ellipsoid volume), and evaluate the ability of 95EV to capture alterations in dynamic balance control, which are not detected by YBT reach distances. Methods: As part of this descriptive laboratory study, 15 healthy participants completed repeated YBTs at 20, 10, and 0 min prior to and following a modified 60-s Wingate test that was used to introduce a short-term reduction in dynamic balance capability. Dynamic balance was assessed using the standard normalised reach distance method, while dynamic balance control during the reach attempts was simultaneously measured by means of the 95EV derived from an inertial sensor, worn at the level of the 4th lumbar vertebra. Results: Intraclass correlation coefficients for the inertial sensor-derived measures ranged from 0.76 to 0.92, demonstrating strong intrasession test-retest reliability. Statistically significant alterations (p < 0.05) in both reach distance and the inertial sensor-derived 95EV measure were observed immediately post-fatigue. However, reach distance deficits returned to baseline levels within 10 min, while 95EV remained significantly increased (p < 0.05) beyond 20 min for all 3 reach distances. Conclusion: These findings demonstrate the ability of an inertial sensor-derived measure to quantify alterations in dynamic balance control, which are not captured by traditional reach distances alone. This suggests that the addition of an inertial sensor to the YBT may provide clinicians and researchers with an accessible means to capture subtle alterations in motor function in the clinical setting. [full text]

Objective:  To provide certified athletic trainers, physicians, and other health care and fitness professionals with recommendations based on current evidence regarding the prevention of noncontact and indirect-contact anterior cruciate ligament (ACL) injuries in athletes and physically active individuals.

Background:  Preventing ACL injuries during sport and physical activity may dramatically decrease medical costs and long-term disability. Implementing ACL injury-prevention training programs may improve an individual’s neuromuscular control and lower extremity biomechanics and thereby reduce the risk of injury. Recent evidence indicates that ACL injuries may be prevented through the use of multicomponent neuromuscular-training programs.

Recommendations:  Multicomponent injury-prevention training programs are recommended for reducing noncontact and indirect-contact ACL injuries and strongly recommended for reducing noncontact and indirect-contact knee injuries during physical activity. These programs are advocated for improving balance, lower extremity biomechanics, muscle activation, functional performance, strength, and power, as well as decreasing landing impact forces. A multicomponent injury-prevention training program should, at minimum, provide feedback on movement technique in at least 3 of the following exercise categories: strength, plyometrics, agility, balance, and flexibility. Further guidance on training dosage, intensity, and implementation recommendations is offered in this statement.

The International Society of Sports Nutrition (ISSN) provides an objective and critical review related to the intake of protein for healthy, exercising individuals. Based on the current available literature, the position of the Society is as follows:

1) An acute exercise stimulus, particularly resistance exercise, and protein ingestion both stimulate muscle protein synthesis (MPS) and are synergistic when protein consumption occurs before or after resistance exercise.

2) For building muscle mass and for maintaining muscle mass through a positive muscle protein balance, an overall daily protein intake in the range of 1.4–2.0 g protein/kg body weight/day (g/kg/d) is sufficient for most exercising individuals, a value that falls in line within the Acceptable Macronutrient Distribution Range published by the Institute of Medicine for protein.

3) There is novel evidence that suggests higher protein intakes (>3.0 g/kg/d) may have positive effects on body composition in resistance-trained individuals (i.e., promote loss of fat mass).

… Grandjean’s influence was felt far beyond Nebraska, said Boyd Epley, Nebraska’s assistant athletic director for strength and conditioning. “She was a tremendous resource. She had a great mind.”

Grandjean began studying hydration during graduate school, noticing that athletes admitted to the hospital in Lubbock, Texas, where she did clinical rotations, were suffering from dehydration and improved with adjustments to their diets.

… “Whenever you’re trying to get something done professionally, to be able to have consistent leadership and foundation upon which to build is important,” Patriots captain Matthew Slater said. “A consistent message, understanding what you’re trying to get done. And we’re fortunate not only with Josh but obviously Coach Belichick and the rest of our coaching staff.

“That consistency with the character of the coach, with the message of the coach, with what he demands of you is important because it helps set a standard. And then when players come in you say, ‘OK this is what’s expected of me and anything less is not going to be good enough.’ ”

Ex-Spurs executive Darren Eales went to Atlanta to launch an MLS team and is now the league’s best boss.

Atlanta United’s English president Darren Eales believes Major League Soccer has entered football’s “global village” and should not be “bashful about being American”.