Applied Sports Science newsletter – September 27, 2018

… Ahead of this week’s Shenzhen Open, Andy Murray sat down for a roundtable discussion with a small handful of journalists. This is what we learned:

He’s feeling 85-90% physically compared to his peak: “That’s from a physical perspective. I still need matches, tournaments and more training. This year has been a lot of starting, playing a couple of tournaments, and then stopping and resting and rehabbing. After New York, I didn’t hit a ball for a couple of weeks. Normally the breaks away from tennis wouldn’t have been as extended, so it’s been difficult to get into a rhythm. Hopefully by the beginning of next year, I’ll be back where I want to be.”

… “I focus on myself and getting better every day. I can’t control [trades], so I don’t really focus on them,” said the 24-year-old. “If it happens, it happens. If it doesn’t, it doesn’t. I’m very blessed to be in this situation. I love this team. I want to play here for a long time, but I know it’s a business.”

If there’s any one specific thing that will help LeVert take that next step, it’s likely his strength development. He worked all offseason closely alongside Nets’ director of sports science, Dan Meehan, mostly working on lower body strength and conditioning.

… Michael Joyner, the Mayo Clinic physiologist and human performance expert who’s been beating the two-hour-marathon drum longer than anyone, has a slightly different take. Sure, a yearly Breaking2-type event funded by a deep-pocketed sponsor would be great, he agrees. But the really interesting question is not what comes next, but who comes next—and how we can generate more Kipchoge-level talents in the not-so-distant future.

Here’s a lightly edited version of a conversation I had with him over email.

The Achilles tendon (AT), the largest tendon in the human body has a unique structural feature, that is the fascicles in the AT display spiral twist. However, their functional and structural roles are still unclear. We used subject-specific computational models and tissue mechanical experiment to quantitatively characterize the role of fascicle twist in the Achilles tendon. Ten subject-specific finite element (FE) models of the Achilles tendon were developed from ultrasound images. Fascicle twist was implemented in these models using the material coordinate system available in our FE framework. Five different angles (0~60°) were implemented and material property optimization was performed for each of them (total 50 sets) using results from uniaxial stretch experiment. We showed that fascicle twist allows for even distribution of stress across the whole tendon, thus improving tissue strength. The predicted rupture load increased up to 40%. A number of connective tissues display similar fascicle twists in their structure. The resulting non-uniform strain distribution has been hypothesized as a primary factor in tissue degeneration and injuries. Therefore, our technique will be used to design biomechanically informed training and rehabilitation protocols for management of connective tissue injuries and degeneration. [full text]

BACKGROUND:

Impact loading in runners, assessed by the measurement of tibial acceleration, has attracted substantial research attention. Due to potential injury links, particularly tibial fatigue fractures, tibial acceleration is also used as a clinical monitoring metric. There are contributing factors and potential limitations that must be considered before widespread implementation.
AIM:

The objective of this review is to update current knowledge of the measurement of tibial acceleration in runners and to provide recommendations for those intending on using this measurement device in research or clinical practice.
METHODS:

Literature relating to the measurement of tibial acceleration in steady-state running was searched. A narrative approach synthesised the information from papers written in English. A range of literature was identified documenting the selection and placement of accelerometers, the analysis of data, and the effects of intrinsic and extrinsic factors.
RESULTS AND DISCUSSION:

Tibial acceleration is a proxy measurement for the impact forces experienced at the tibia commonly used by clinicians and researchers. There is an assumption that this measure is related to bone stress and strain, however this is yet to be proven. Multi-axis devices should be secured firmly to the tibia to limit movement relative to the underlying bone and enable quantification of all components of acceleration. Additional frequency analyses could be useful to provide a more thorough characterisation of the signal.
CONCLUSIONS:

Tibial accelerations are clearly affected by running technique, running velocity, lower extremity stiffness, as well as surface and footwear compliance. The interrelationships between muscle pre-activation and fatigue, stiffness, effective mass and tibial acceleration still require further investigation, as well as how changes in these variables impact on injury risk.

… Athletes with hang time like Ungar have long fascinated lesser leapers like myself. Track and field phenom Ray Ewry—Gold medalist in the standing high jump at the 1900, 1904, 1906, and 1908 Olympic Games—once cleared a bar 65 inches high. For decades, the vertical jump has been a hallmark event in the strength and agility tests undergone by draft prospects at the NFL combine. More recently, YouTube has helped elevate athletes like Ungar to celebrity status in CrossFit circles and online message boards.

It’s not hard to see why. What Ungar does is remarkable: When he performs a box jump, he faces his target, springs subtly toward it, and—this is the important bit—shunts his knees toward his armpits. That final midair maneuver raises his feet nearly to the level of his hips, where, if all goes as planned, they alight atop his landing zone right as he reaches the apex of his flight. In a well-timed box jump, Ungar’s feet touch down right as his upward velocity and downward velocity equal zero. The result is a surprisingly gentle landing.

Researchers tied three behaviors to higher scores on tests of mental ability in children: at least 60 minutes of physical activity a day, nine to 11 hours of sleep a night, and no more than two hours a day of recreational screen time.

The new study, in Lancet Child & Adolescent Health, included 4,524 children ages 8 to 11 who were assessed with six standard tests that measure language skills, memory, planning ability, and speed at completing mental tasks.

Compared with those who met none of the three behavioral criteria, those who met all of them scored about 4 percent higher on the combined tests. Meeting the requirements for both screen time and sleep was associated with a 5.1 percent increase in scores compared with those who met neither. Only 5 percent of the children met all three criteria, and nearly 30 percent met none.

… The company is in the process of developing a continuous blood pressure monitoring bracelet designed to help patients with hypertension. According to the CDC, hypertension affects one of three adults in the US, but only 54 percent of that has their blood pressure under control. Hypertension is linked to an increased risk of heart disease and stroke.

Pforr said the company is looking to make blood pressure checks less awkward and stressful for patients, and by doing so increase the accuracy of those measurements..

We may not think about them much, but antennas are everywhere. In our phones, in our cars, in the anti-theft tags on the clothes we buy, and as the Internet of Things becomes an ever-more-present reality, they’re showing up in new places, like microwaves and lamps. Engineers have therefore been looking for methods of making antennas smaller, lighter and easier to apply.

Now, researchers at Drexel University have developed a method for creating nearly invisible antennas on almost any surface by literally spraying them on like paint. The antennas are made from a special two-dimensional metallic material called MXene. MXene powder can be dissolved in water to create a paint that is then airbrushed on. In tests, even a layer as thin as just 62 nanometers – thousands of times thinner than a sheet of paper – could communicate effectively. Performance maxed out at just 8 microns, a point at which the spray-on antennas worked just as well as those currently used in mobile devices and wireless routers.

Researchers from the University of Glasgow have developed a new device which pairs a handheld CMOS sensor with an Android-based smartphone or tablet app to measure the levels of various metabolites in fluid samples from patients, enabling simple detection of chronic heart conditions and prostate cancer.

The ability to rapidly detect and quantify multiple metabolite biomarkers simultaneously makes this device particularly useful in cases of heart attack, cancer and stroke, where rapid diagnosis is vital for effective treatment.

Caffeine is a well-established ergogenic aid, demonstrated to enhance performance across a wide range of capacities through a variety of mechanisms. As such, it is frequently used by both athletes and non-athletes alike. As a result, caffeine ingestion is ubiquitous in modern society, with athletes typically being exposed to regular non-supplemental caffeine through a variety of sources. Previously, it has been suggested that regular caffeine use may lead to habituation and subsequently a reduction in the expected ergogenic effects, thereby blunting caffeine’s performance-enhancing impact during critical training and performance events. In order to mitigate this expected performance loss, some practitioners recommended a pre-competition withdrawal period to restore the optimal performance benefits of caffeine supplementation. However, at present the evidence base exploring both caffeine habituation and withdrawal strategies in athletes is surprisingly small. Accordingly, despite the prevalence of caffeine use within athletic populations, formulating evidence-led guidelines is difficult. Here, we review the available research regarding habitual caffeine use in athletes and seek to derive rational interpretations of what is currently known—and what else we need to know—regarding habitual caffeine use in athletes, and how athletes and performance staff may pragmatically approach these important, complex, and yet under-explored phenomena. [full text]

If low-fat yogurt is blended with fatty ingredients like coconut or chocolate, is it still low-fat? Is it even yogurt?

The U.S. government has rules about what can be called “yogurt,” and the dairy industry says it’s not clear what the answers are. Now it’s hopeful it will finally get to use the term with greater liberty, with the Trump administration in the process of updating the yogurt definition.

The industry push to open up the yogurt standard illustrates how fraught it can be to define a food, especially as manufacturing practices and consumer tastes change.

OBJECTIVES:

Registered exercise professionals (REP) are trained to provide structured exercise recommendations and general nutrition advice to healthy clients. However REP provide specific nutrition advice beyond their scope of practice, including diet-disease advice. The present study aims to investigate the level of general nutrition knowledge of REP, and compare this to a sample of community members (CTM), and university trained dietitians (DN).
DESIGN:

Age-matched REP, CTM and DN were recruited to complete the previously validated revised-general nutrition knowledge questionnaire.
METHODS:

Total nutrition knowledge score and section scores were compared between REP, CTM and DN. The impact of sex, age, level of education, and years’ experience on nutrition knowledge was investigated.
RESULTS:

A total of 554 participants completed the questionnaire (REP, n=161; CTM, n=357; DN, n=36). The DN group performed significantly better overall (DN, 91.2±4.6; REP, 78.4±9.6; CTM, 75.4±11.3) and for knowledge of dietary guidelines (DN, 82.3±20.7; REP, 80.5±15.5; CTM, 80.0±14.1), nutrient content of foods (DN, 92.6±4.4; REP, 80.9±9.9; CTM, 75.7±12.0), and diet-disease relationships (DN, 91.4±9.7; REP, 65.4±18.0; CTM, 68.6±11.1) compared to the REP and CTM groups (p<0.001). Sex, education and age were all significant predictors of total nutrition knowledge (p<0.0005). CONCLUSIONS:

Total nutrition knowledge and knowledge of diet-disease relationships is limited in REP. Encouraging REP to work collaboratively with a multidisciplinary team, including DN, will assist in providing optimal client care in achieving health and body composition related goals.

… The Sixers came to believe that Brand has leadership skill and potential that their other executives didn’t have, or didn’t have enough of at a time when Philly is poised to again become a power in the east. They think Brand will be able to provide hands-on teaching and motivating some of their young players. They think he’ll be able to collaborate with and occasionally push back on Brown and the coaching staff.

And they think Brand’s status as a former player will help them both with their team and with potential free agents.

It’s a formula that’s worked in the league in recent years. But it’s nonetheless a gamble.

… Giants team president Larry Baer told reporters Monday that the team planned to look outside the organization and described the new GM they envision this way:

“Sort of a ‘next-gen’ general manager, if you will. Somebody who’s going to be head of baseball ops. People will say, ‘new school vs. old school’; people will say, ‘analytics vs. scouting.’ And I think that the new, next-generation general manager is able to do both, and we will bring both into the mix.”

McLeod, who grew up in San Diego, worked with Giants manager Bruce Bochy when both were with the Padres, Bochy managing and McLeod working as a minor-league coach and in the scouting and player-development department.