Applied Sports Science newsletter – September 1, 2015

One of the truisms of being a professional athlete is the constant travel. East Coast. West Coast. Late-night games and overnight flights. There is no escaping the draining demands of criss-crossing the continent, sandwiched between arena stops where the athletes are expected to deliver their absolute best on any given day.

Finding the time to get enough quality sleep to maintain that level of athletic ability has consequently never been of greater importance to coaches and training staff.

When Danton Cole played hockey, he wouldn’t have ever been described as a star – but he got a star’s hockey education.

Throughout his 11-year professional career, Cole played under Hall of Famers and Stanley Cup winners, ranging from Jacques Lemaire to Larry Robinson and Terry Crisp. Before turning pro, he played four seasons at Michigan State University for Ron Mason, still the second-winningest coach in NCAA Division I hockey history.

Cole has parlayed the lessons he learned under some of the brightest minds in hockey to become one of the top coaches in the United States at developing young players.

A plan unveiled Friday called for a new Manufacturing Innovation Institute to work on new kinds of flexible technology that can be used both on the battlefield or for civilian health, smart homes and cities.

Nanoengineers at the University of California, San Diego used an innovative 3D printing technology they developed to manufacture multipurpose fish-shaped microrobots — called microfish — that swim around efficiently in liquids, are chemically powered by hydrogen peroxide and magnetically controlled. These proof-of-concept synthetic microfish will inspire a new generation of “smart” microrobots that have diverse capabilities such as detoxification, sensing and directed drug delivery, researchers said.

Stephen Smith, founder and chief executive officer at Kitman Labs, explains the company’s use of big data to predict and prevent sports injuries. He speaks on “Bloomberg Markets.”

… Within organs, cells connect, communicate, and interact with one another in all directions. But this 3D organization is rarely recreated in tissue culture dishes. In recent years, researchers have developed a variety of techniques—including scaffolds, cell-filled hydrogel building blocks, and even bioprinting—to assemble cells into 3D organ-like arrangements. The goal is not only to aid basic research into tissue and organ biology but, ultimately, to construct functional tissues for medical use—such as cardiac muscle patches to fix damaged hearts.

However, “all of the other methods that were available were not adequate,” said Milica Radisic, the Toronto tissue engineer who led the new study. One problem with the printing approach, she said, is that although the cells can be precisely positioned, they are not immediately functional—it takes time to establish the cells’ morphologies and connections. “With our Tissue-Velcro approach you can have these individual thin layers premade and, say, even at the time of surgery you could stack it to the desired height and it would be immediately functional.”

Why, among players experiencing similar magnitude and number of blows to the head, so some sustained concussions and others do not. To answer the question, researchers at Purdue University followed a group of high school football players over the course of the two seasons.

… The surgery is only the beginning of a long road to recovery.

“After the graft matures and takes on the properties of a ligament, there’s all the external stuff the player has to deal with,” said Stephania Bell, a physical therapist and injury analyst at ESPN. “The player has to get their range of motion back, their strength back and they have to gradually resume their activity. You literally have to relearn how to walk, and from that you go to running and from that to a highly complex skill set which you need to play football.”

While the science behind ACL injuries, surgeries and rehab can be easily explained with diagrams and knee models, the emotional and psychological recovery can be fully understood only through experience.

The research is pretty clear that people who regularly get enough sleep have healthier body weights than people who skimp on shut-eye. Whether that is because sleep keeps weight in check, people with better body weights sleep more soundly or some other reason is unknown.

Hassan Dashti, Ph.D., N12, N15, may have found a connection between sleeping and the food choices people make that helps explain it.

Everyone from weekend warriors to pro athletes has to consider what kind of foods fuel peak performance — and for nonathletes, the same kinds of decisions are crucial for overall health. “Integrative and sports nutritionists work with athletes and patients to develop an individualized approach to consuming foods that best improve our health and well-being,” says McDonald. “It’s not a one-size-fits-all approach to nutrition; we look at the whole person, including their lifestyle choices and environmental exposures, not just their blood work or weight on the scale.”

The assessment of dietary attitudes and behaviours provides information of interest to sports nutritionists. Although there has been little analysis of the quality of research undertaken in this field, there is evidence of a number of flaws and methodological concerns in some of the studies in the available literature. This review undertook a systematic assessment of the attributes of research assessing the nutrition knowledge and attitudes of athletes and coaches. Sixty questionnaire-based studies were identified by a search of official databases using specific key terms with subsequent analysis by certain inclusion-exclusion criteria. These studies were then analyzed using 33 research quality criteria related to the methods, questionnaires and statistics used. We found that many studies did not provide information on critical issues such as research hypotheses (92%), the gaining of ethics approval (50%) or informed consent (35%), or acknowledgement of limitations in the implementation of studies or interpretation of data (72%). Many of the samples were non-probabilistic (85%) and rather small (42%). Many questionnaires were of unknown origin (30%), validity (72%) and reliability (70%), and resulted in low (? 60%) response rates (38%). Pilot testing was not undertaken in 67% of the studies. Few studies dealt with sample size (2%), power (3%), assumptions (7%), confidence intervals (3%) or effect sizes (3%). Improving some of these problems and deficits may enhance future research in this field.

Different jump and sprint tests have been used to assess neuromuscular fatigue, but the test with optimal validity remains to be established. The current investigation examined the suitability of vertical jump (countermovement jump [CMJ], squat jump [SJ], drop jump [DJ]) and 20-m sprint (SPRINT) testing for neuromuscular fatigue detection. On 6 separate occasions, 11 male team-sport athletes performed 6 CMJ, SJ, DJ, and 3 SPRINT trials. Repeatability was determined on the first 3 visits, with subsequent 3 visits (0-, 24-, and 72-hour postexercise) following a fatiguing Yo-Yo running protocol. SPRINT performance was most repeatable (mean coefficient of variation ?2%), whereas DJ testing (4.8%) was significantly less repeatable than CMJ (3.0%) and SJ (3.5%). Each test displayed large decreases at 0-hour (33 of 49 total variables; mean effect size = 1.82), with fewer and smaller decreases at 24-hour postexercise (13 variables; 0.75), and 72-hour postexercise (19 variables; 0.78). SPRINT displayed the largest decreases at 0-hour (3.65) but was subsequently unchanged, whereas SJ performance recovered by 72-hour postexercise. In contrast, CMJ and DJ performance displayed moderate (12 variables; 1.18) and small (6 variables; 0.53) reductions at 72-hour postexercise, respectively. Consequently, the high repeatability and immediate and prolonged fatigue-induced changes indicated CMJ testing as most suitable for neuromuscular fatigue monitoring.

PURPOSE:

To explore the association between in-season training load measures and injury risk in professional Rugby Union players. Methods This was a one-season prospective cohort study of 173 Professional Rugby Union players from four English Premiership teams. Training load (duration x session-RPE) and time-loss injuries were recorded for all players for all pitch and gym based sessions. Generalised estimating equations were used to model the association between in-season training load measures and injury risk in the subsequent week.
RESULTS:

Injury risk increased linearly with one-week loads and week-to-week changes in loads, with a 2 standard deviation (SD) increase in these variables (1245 AU and 1069 AU, respectively) associated with odds ratios of 1.68 (95% CI 1.05-2.68) and 1.58 (95% CI: 0.98-2.54). When compared with the reference group (8651 AU (OR: 1.39, 95% CI: 0.98-1.98).
CONCLUSIONS:

Players had an increased risk of injury if they had high one-week cumulative loads (1245 AU), or large week-to-week changes in load (1069 AU). In addition, a ‘U-shaped’ relationship was observed for four-week cumulative loads, with an apparent increase in risk associated with higher loads (>8651 AU). These measures should therefore be monitored to inform injury risk reduction strategies.

PURPOSE:

To investigate the effects of mental fatigue on soccer-specific physical and technical performance.
METHODS:

This investigation consisted of two separate studies. Study 1 assessed the soccer-specific physical performance of 12 moderately-trained soccer players using the Yo-Yo Intermittent Recovery Test, Level 1 (Yo-Yo IR1). Study 2 assessed the soccer-specific technical performance of 14 experienced soccer players using the Loughborough Soccer Passing and Shooting Tests (LSPT, LSST). Each test was performed on two occasions and preceded, in a randomized, counter-balanced order, by 30-min of the Stroop task (mentally fatiguing treatment) or 30-min of reading magazines (control treatment). Subjective ratings of mental fatigue were measured before and after treatment, and mental effort and motivation were measured after treatment. Distance run, heart rate (HR) and ratings of perceived exertion (RPE) were recorded during the Yo-Yo IR1. LSPT performance time was calculated as original time plus penalty time. LSST performance was assessed using shot speed, shot accuracy and shot sequence time.
RESULTS:

Subjective ratings of mental fatigue and effort were higher following the Stroop task in both studies (P < 0.001), while motivation was similar between conditions. This mental fatigue significantly reduced running distance in the Yo-Yo IR1 (P < 0.001). No difference in HR existed between conditions, while RPE was significantly higher at iso-time in the mental fatigue condition (P < 0.01). LSPT original time and performance time were not different between conditions, however penalty time significantly increased in the mental fatigue condition (P = 0.015). Mental fatigue also impaired shot speed (P = 0.024) and accuracy (P < 0.01), while shot sequence time was similar between conditions.
CONCLUSION:

Mental fatigue impairs soccer-specific running, passing, and shooting performance.