Applied Sports Science newsletter – October 15, 2015

Sir Alex Ferguson has morphed from soccer coaching legend to wise man of management—or at least that’s the plan.

The 73-year-old Ferguson, who won 38 trophies in 26 years coaching Manchester United just released his third book: Leading: Learning From Life and My Years at Manchester United, written with Michael Moritz, the Sequoia Capital executive. The book is 400 pages of anecdotes and musings culled from Ferguson’s years as a player and manager arranged to provide lessons about everything from inspiring excellence, to developing new talent from within an organization.

… His story — his team’s story — isn’t for sale. It’s private, sacred. Popovich gripes bookshelves are cluttered with “how to” manuals from coaches, a phenomenon, he once confided, “makes me puke.”

Pop’s own success stems from an intuition of sensing potential discord before it materializes. Former Spurs assistant (and current Sixers coach) Brett Brown likens it to a mother who knows her children are going to be sick before they exhibit symptoms.

PURPOSE:

To examine how match performance parameters in trained footballers relate to skeletal muscle parameters, sprint ability and intermittent exercise performance.
METHODS:

19 male elite football players completed an experimental game with physical performance determined by video analysis and exercise capacity assessed by intermittent Yo-Yo IR1 and IR2 tests, and a repeated sprint test (RST). Muscle tissue was obtained for analysis of metabolic enzyme maximal activity and key muscle protein expression.
RESULTS:

Total game distance, distance deficit from first to second half and high-intensity running in the final 15 min of the game were all correlated to the players’ Yo-Yo IR1 performance (r = 0.55-0.87) and beta-hydroxyacyl-CoA-dehydrogenase (HAD) maximal activity (r = 0.55-0.65). Furthermore, platelet/endothelial cell adhesion molecule-1 (PECAM1) protein expression was weakly (r = 0.46) correlated to total game distance. Peak 5-min game distance faster than 21 km h-1 was related to the Na+-K+ ATPase subunit (?1, ?2, ?1 and FXYD1) protein levels (r = 0.54-0.70), while Yo-Yo IR2 performance explained 40 % of the variance in high-intensity game distance. Total and 1-min peak sprint distance correlated to myosin heavy chain II/I ratio (MHCII/I ratio) and sarcoendoplasmic reticulum Ca2+ ATPase isoform-1 (SERCA1) protein (r = 0.56-0.86), while phosphofructokinase (PFK) maximal activity also correlated to total sprint distance (r = 0.46).
CONCLUSION:

The findings emphasize the complexity of parameters predicting physical football performance with Yo-Yo IR1 and HAD as the best predictors of total distance, while high expression of Na+-K+ ATPase proteins and the Yo-Yo IR2 test are better predictors of high-intensity performance. Finally, sprint performance relates to skeletal muscle fiber-type composition.

Training load (TL) is monitored with the aim of making evidence-based decisions on appropriate loading schemes to reduce injuries and enhance team performance. However little is known in detail about the variables of load and methods analysis used in high level football. Therefore the aim of this study was to provide information on the practices and perceptions of monitoring in professional clubs. Eighty two high-level football clubs from Europe, the United States and Australia were invited to answer questions relating to (1) how TL is quantified; (2) how players’ responses are monitored, and (3) their perceptions of the effectiveness of monitoring. Forty one responses were received. All teams used GPS and heart rate monitors during all training sessions and 28 used RPE. The top 5 ranking TL variables were; acceleration (various thresholds), total distance, distance covered above 5.5 m·s-1,estimatedmetabolic power, and heart rate exertion. Players’ responses to training are monitored using questionnaires (68% of clubs) and submaximal exercise protocols (41%). Differences in expected vs. actual effectiveness of monitoring were 23% and 20% for injury prevention and performance enhancement respectively (P<0.001 d=1.0 to 1.4). Of the perceived barriers to effectiveness, “limited human resources” scored highest, followed by “coach buy-in”. The discrepancy between expected and actual effectiveness appears to be due to suboptimal integration with coaches, insufficient human resources and concerns over the reliability of assessment tools. Future approaches should critically evaluate the usefulness of current monitoring tools and explore methods of reducing the identified barriers to effectiveness.

… This article, however, is not about my experiences or credentials as a coach (most level-headed coaches will tell you that in the end, a good player makes a good coach, not the other way around) but rather about the changes to high school programs in America, the conflict with academy programs and what it means for the future of US youth soccer.

******

On 10 February 2012, less than a year into Klinsmann’s tenure, the US Soccer Development Academy announced the birth of the 10-month season for all the youth clubs and players affiliated with the program. This meant that high-school kids who also played academy had a choice to make: one or the other.

Kentucky’s team room in the E.J. Nutter Training Facility looks much the same as it did when coach Mark Stoops arrived in Lexington three years ago. The primary differences are a pair of blue signs hanging on the main wall at the front of the oversized auditorium. One lists the program’s core values: character, attitude, accountability, dependability, all-in. Just to the right, a similar poster touts the Wildcats’ guiding principles, including no shortcuts and do the right thing.

Stoops, Kentucky’s third-year head coach, had both signs put up after he took the Wildcats job in December 2012. The longtime assistant coach had inherited a program that had won just four SEC games in the previous three seasons. Before Stoops could help Kentucky win, he had to convince the Wildcats that winning was possible. Cultivating an attitude of belief was crucial in the locker room, an important aspect of his overhaul of the program’s culture.

… “Relax,” the psychologist and former teacher Michele Borba reminds me when I email to fret about the swim coach’s observation that Finn’s “a sinker,” or Ben’s inability to ride a bike well into his tweens. “Einstein didn’t say his first word until he was 4. Stop rubbernecking on the playground, Jess; childhood is not a race. Stay calm and support your child. If you are really wor

Moments of confusion can be pretty memorable, and not in a good way. How is this thing supposed to work? What is the teacher’s point? Where am I, and how do I get to where I am going? But confusion is greatly underrated, argues the journalist Jamie Holmes in his new book, Nonsense. Naturally, it is good to understand. Yet, Holmes writes, our discomfort with not knowing can lead us astray — to bad solutions, or to brilliant options never spotted. If we could learn to embrace uncertainty, we’d all be better off — and better prepared for modern life. Holmes answered questions from Mind Matters editor Gareth Cook.

With muscular training, the central nervous system may regulate motor unit firing rates to sustain force output and delay fatigue. The aims of this study were to investigate motor unit firing rates and patterns of the adductor pollicis (AdP) muscle in young, able-bodied adults throughout a sustained submaximal isometric fatiguing contraction and postactivation potentiation pre-post 4 weeks of muscular endurance training. Fifteen participants (training group: N = 10; control group: N = 5) performed maximal voluntary contractions (MVCs) and a sustained isometric 20 % MVC fatigue task pre-post training. Single-motor-unit potentials were recorded from the AdP during the fatigue task with intramuscular fine-wire electrodes. Twitch force potentiation was measured during single-pulse electrical stimulation of the ulnar nerve before and after MVCs. The training group endurance trained their AdP muscle at 20 % MVC for 4 weeks. Mean motor unit firing rates were calculated every 5 % of endurance time (ET). ET increased by 45.2 ± 8.7 % (p < 0.001) following muscular endurance training. Although ET increased, mean motor unit firing rates during the fatigue task did not change significantly with training. The general motor unit firing pattern consisted of an initial slowing followed by an increase in firing rate late in fatigue and remained consistent pre-post training. Potentiation did not change following training. These data suggest that the ability of the neuromuscular system to sustain motor unit firing rate may serve as a mechanism to augment the duration of submaximal muscle performance and delay muscular fatigue.

Under Armour founder and CEO Kevin Plank remembers his company’s humble beginnings in 1996, when the business ran out of “a little rowhouse” in Georgetown and earned approximately $17,000 in revenue.

Nineteen years later, the company is approaching $4 billion, but Plank, who spoke at the espnW Summit on Wednesday regarding the business of women in sports apparel, lamented that his business is still lagging far behind in innovation and technology.

Background

Activity trackers can potentially stimulate users to increase their physical activity behavior. The aim of this study was to examine the reliability and validity of ten consumer activity trackers for measuring step count in both laboratory and free-living conditions.
Method

Healthy adult volunteers (n?=?33) walked twice on a treadmill (4.8 km/h) for 30 min while wearing ten different activity trackers (i.e. Lumoback, Fitbit Flex, Jawbone Up, Nike+?Fuelband SE, Misfit Shine, Withings Pulse, Fitbit Zip, Omron HJ-203, Yamax Digiwalker SW-200 and Moves mobile application). In free-living conditions, 56 volunteers wore the same activity trackers for one working day. Test-retest reliability was analyzed with the Intraclass Correlation Coefficient (ICC). Validity was evaluated by comparing each tracker with the gold standard (Optogait system for laboratory and ActivPAL for free-living conditions), using paired samples t-tests, mean absolute percentage errors, correlations and Bland-Altman plots.
Results

Test-retest analysis revealed high reliability for most trackers except for the Omron (ICC .14), Moves app (ICC .37) and Nike+?Fuelband (ICC .53). The mean absolute percentage errors of the trackers in laboratory and free-living conditions respectively, were: Lumoback (?0.2, ?0.4), Fibit Flex (?5.7, 3.7), Jawbone Up (?1.0, 1.4), Nike+?Fuelband (?18, ?24), Misfit Shine (0.2, 1.1), Withings Pulse (?0.5, ?7.9), Fitbit Zip (?0.3, 1.2), Omron (2.5, ?0.4), Digiwalker (?1.2, ?5.9), and Moves app (9.6, ?37.6). Bland-Altman plots demonstrated that the limits of agreement varied from 46 steps (Fitbit Zip) to 2422 steps (Nike+?Fuelband) in the laboratory condition, and 866 steps (Fitbit Zip) to 5150 steps (Moves app) in the free-living condition.
Conclusion

The reliability and validity of most trackers for measuring step count is good. The Fitbit Zip is the most valid whereas the reliability and validity of the Nike+?Fuelband is low.

During Sunday’s Chicago Marathon, it was easy to pick American Luke Puskedra out of the pack, and not just because his singlet read “USA.” With a personal best of 2:10:24 and a height of 6 feet 4 inches, Puskedra is the newest entry on a short list—top marathoners who are at least 6 feet tall.

Puskedra is tall enough to stand out in almost any crowd, but especially in comparison to his fellow elites. As reported in a 2013 Sweat Science column, between 1990 and 2012 the average height of the top 100 men marathoners in a given year decreased from 5 feet 8.1 inches to 5 feet 6.9 inches.

Denver Broncos head coach Gary Kubiak is in the minority. While an old-school coach in some ways (he still appreciates paper playbooks), he’s unafraid of new technologies.

So hearing him say he finds comfort in having Mitch Tanney, the team’s director of football analytics, stationed in the coaches’ booth during games should come as no surprise.

“When you’re calling plays and involved in the game and yet you’re involved in the time, all of a sudden, you’ve got somebody up there who is totally involved in that,” Kubiak told local media last Friday. “I just listen to him, ‘Hey, Mitch, talk to me here. What do you think?’ He’s in my ear the whole time. It’s a very comforting thing.”

This study investigated exposure to periods of match congestion in regular starter players in a professional soccer team across 4 competitive seasons (2009–2013). Players were divided into 2 groups: club players (club match exposure only, n = 41) and national team players (club and national team exposure, n = 22). The frequency of congested periods that players were potentially exposed to per season was initially determined: 2-match cycles – potential exposure to 2 successive matches separated by a ? 3-day interval calculated immediately from the end of play in match 1 to the start of play in match 2 occurred on 12.5 ± 5.1 and 16.0 ± 4.7 occasions for club and national team players, respectively. Multiple-match cycles: potential exposure to 3-, 4-, 5- or 6-matches played successively within a ? 4-day period commencing from the day after each match occurred on 8.5 ± 2.1, 4.3 ± 1.7, 3.0 ± 0.8 and 1.8 ± 0.5 occasions for club and 11.5 ± 2.4, 6.5 ± 0.6, 4.5 ± 1.9 and 3.0 ± 1.4 occasions for national team players, respectively. With regard to actual exposure in club and national team players, respectively, participation in both matches in 2-match cycles attained 61.2% and 59.3% while 90-min play in both matches was only completed on 38.2% and 40.5% of occasions and ?75-min play on 47.6% and 50.0% of occasions, despite availability to play in both groups being >86%. While availability to play in all players was frequently >70% for multiple-match cycles, a trend was observed for a sharp decline in participation as the number of matches in the cycles increased. Therefore, the present players were not extensively exposed to periods of fixture congestion.