Applied Sports Science newsletter – May 26, 2015

Applied Sports Science news articles, blog posts and research papers for May 26, 2015

 

Angelo Esposito’s story is cautionary tale for all teenaged hockey phenoms | Toronto Star

Toronto Star from May 25, 2015

Given all the hype surrounding Connor McDavid the past few years, and what Auston Matthews will go through next year, it’s worth considering the plight of Angelo Esposito.

He was a hockey sensation at 16 — 98 points in 57 games in his first year of junior hockey. He was a Memorial Cup champion and the presumptive No. 1 overall pick for the 2007 draft.

Things have not worked out well for Esposito.

 

How a Fax Helped Rewrite Women’s Soccer in the U.S. – NYTimes.com

The New York Times from May 25, 2015

… Here’s a sad fact: Nearly two decades after Rampone rose to the national team out of virtually nowhere, the Rampones of the world are all but extinct. Today, multisport athletes like her might not even be noticed because there are so many athletes who commit to a single sport early and for years command the attention of national team coaches.

Carefree fun has dwindled. Injuries abound from overuse. But specialization in women’s sports comes with their growth and progress. Two things exist now that didn’t when Rampone was young: the lure of plentiful scholarships and the possibility of making a living by playing in a women’s pro league. That means specialization is not going away any time soon.

 

The endogenous molecular clock orchestrates the temporal separation of substrate metabolism in skeletal muscle – Springer

Skeletal Muscle from May 16, 2015

Background
Skeletal muscle is a major contributor to whole-body metabolism as it serves as a depot for both glucose and amino acids, and is a highly metabolically active tissue. Within skeletal muscle exists an intrinsic molecular clock mechanism that regulates the timing of physiological processes. A key function of the clock is to regulate the timing of metabolic processes to anticipate time of day changes in environmental conditions. The purpose of this study was to identify metabolic genes that are expressed in a circadian manner and determine if these genes are regulated downstream of the intrinsic molecular clock by assaying gene expression in an inducible skeletal muscle-specific Bmal1 knockout mouse model (iMS-Bmal1 ?/? ).
Methods
We used circadian statistics to analyze a publicly available, high-resolution time-course skeletal muscle expression dataset. Gene ontology analysis was utilized to identify enriched biological processes in the skeletal muscle circadian transcriptome. We generated a tamoxifen-inducible skeletal muscle-specific Bmal1 knockout mouse model and performed a time-course microarray experiment to identify gene expression changes downstream of the molecular clock. Wheel activity monitoring was used to assess circadian behavioral rhythms in iMS-Bmal1 ?/? and control iMS-Bmal1 +/+ mice.
Results
The skeletal muscle circadian transcriptome was highly enriched for metabolic processes. Acrophase analysis of circadian metabolic genes revealed a temporal separation of genes involved in substrate utilization and storage over a 24-h period. A number of circadian metabolic genes were differentially expressed in the skeletal muscle of the iMS-Bmal1 ?/? mice. The iMS-Bmal1 ?/? mice displayed circadian behavioral rhythms indistinguishable from iMS-Bmal1 +/+ mice. We also observed a gene signature indicative of a fast to slow fiber-type shift and a more oxidative skeletal muscle in the iMS-Bmal1 ?/? model.
Conclusions
These data provide evidence that the intrinsic molecular clock in skeletal muscle temporally regulates genes involved in the utilization and storage of substrates independent of circadian activity. Disruption of this mechanism caused by phase shifts (that is, social jetlag) or night eating may ultimately diminish skeletal muscle’s ability to efficiently maintain metabolic homeostasis over a 24-h period.

 

Skeletal Muscle Fatigue and Decreased Efficiency: Two Sides of the Same Coin?

Exercise and Sport Sciences Reviews from April 01, 2015

During high-intensity submaximal exercise, muscle fatigue and decreased efficiency are intertwined closely, and each contributes to exercise intolerance. Fatigue and muscle inefficiency share common mechanisms, for example, decreased “metabolic stability,” muscle metabolite accumulation, decreased free energy of adenosine triphosphate breakdown, limited O2 or substrate availability, increased glycolysis, pH disturbance, increased muscle temperature, reactive oxygen species production, and altered motor unit recruitment patterns.

 

Gym Injuries, Experts Explain The Best Ways To Avoid Injuries While Working Out

AskMen from May 22, 2015

Do you ever wish you had a time machine, if for no other reason that you could go back and tell your younger self not to do some dumbass thing? I think it was Albert Einstein who said something about paradoxes and ripping apart the space-time continuum and all the atoms in the universe exploding in an instantaneous nuclear hellfire, so … never mind that.

Since the time machine thing is off the table, perhaps we can prevent some future dumbass things from taking place. Specifically, maybe we can stop you from getting injured in the gym. “No pain, no gain” is a myth. If you’re somewhat new to lifting, or even a seasoned gym rat, the information we provide in this article can keep you whole for decades to come, so future grandpa you doesn’t have to give up his gym membership because he’s accumulated too many owies.

I kept saying “we.” This is not a royal “we.” I talked to a bunch of smart people for this piece.

 

Firstbeat: Measuring Training Load and Recovery on a Training Camp – Part 2: How Does Training Hard Affect Recovery?

Firstbeat from May 25, 2015

In this post I aim to present some data I have got from conducting measurements with the Bodyguard 2 device during training camp here at Tenerife.

The interesting part for me as an athlete is to see how well my body recovers during sleep when practicing hard. Firstbeat enables me to see how my body reacts on training as well as measure the quality of my sleep.

 

Hacking the Brain – The Atlantic

The Atlantic from May 20, 2015

… What’s possible now, and what may one day be? In a series of conversations with neuroscientists and futurists, I glimpsed a vision of a world where cognitive enhancement is the norm. Here’s what that might look like, and how we can begin thinking about the implications.

 

MediaTek’s Linkit One Platform Could Make Makers Of Us All

ReadWrite from May 25, 2015

MediaTek, a Taiwan-based semiconductor company, took to the Wearable World Congress floor last week to show off a new way for makers to bring their ideas off the drawing board and into the real world. Priced at just $79, the LinkIt One development kit seems geared specifically for tomorrow’s Internet of Things and wearable tech entrepreneurs.

 

Gyro’s the next thing in wearable technology, see our interview in Electronics Letters

QSTC/SABEL Labs from May 25, 2015

Accelerometers are now the mainstay in wearable technology, why, because they are cheap to buy and cheap to run – now only consuming microamps of power. Rate gyroscopes are a close cousin that yield important but different metrics of human movement. Rate gyros traditionally have been a bit thirsty, but thanks to recent trends in development they are about to become the next big thing in wearables.

 

Enhanced Glycogen Storage of a Subcellular Hot Spot in Human Skeletal Muscle during Early Recovery from Eccentric Contractions

PLOS One from May 21, 2015

Unaccustomed eccentric exercise is accompanied by muscle damage and impaired glucose uptake and glycogen synthesis during subsequent recovery. Recently, it was shown that the role and regulation of glycogen in skeletal muscle are dependent on its subcellular localization, and that glycogen synthesis, as described by the product of glycogen particle size and number, is dependent on the time course of recovery after exercise and carbohydrate availability. In the present study, we investigated the subcellular distribution of glycogen in fibers with high (type I) and low (type II) mitochondrial content during post-exercise recovery from eccentric contractions. Analysis was completed on five male subjects performing an exercise bout consisting of 15 x 10 maximal eccentric contractions. Carbohydrate-rich drinks were subsequently ingested throughout a 48 h recovery period and muscle biopsies for analysis included time points 3, 24 and 48 h post exercise from the exercising leg, whereas biopsies corresponding to prior to and at 48 h after the exercise bout were collected from the non-exercising, control leg. Quantitative imaging by transmission electron microscopy revealed an early (post 3 and 24 h) enhanced storage of intramyofibrillar glycogen (defined as glycogen particles located within the myofibrils) of type I fibers, which was associated with an increase in the number of particles. In contrast, late in recovery (post 48 h), intermyofibrillar, intramyofibrillar and subsarcolemmal glycogen in both type I and II fibers were lower in the exercise leg compared with the control leg, and this was associated with a smaller size of the glycogen particles. We conclude that in the carbohydrate-supplemented state, the effect of eccentric contractions on glycogen metabolism depends on the subcellular localization, muscle fiber’s oxidative capacity, and the time course of recovery. The early enhanced storage of intramyofibrillar glycogen after the eccentric contractions may entail important implications for muscle function and fatigue resistance.

 

The pace of Romelu Lukaku Saido Berahino and Danny Welbeck – ESPN FC

ESPN FC, Michael Cox from May 25, 2015

As football changes stylistically, the perceived value of individual attributes often changes dramatically.

Over the past couple of decades, the quality that has enjoyed the biggest surge in demand is simple: pace. Once viewed as a handy bonus for an attacker, it’s now become a pre-requisite for almost every position, to the extent that even goalkeepers are criticised for being slow off their line.

 

Why John Nash Matters | FiveThirtyEight

FiveThirtyEight, DataLab from May 25, 2015

… One area in which Nash’s legacy continues to be especially relevant and fruitful is sports analysis. One of the cleanest examples is the mini-game of penalty kicks in soccer. If a player always kicks the same direction, the goalkeeper can profitably adapt by always diving in that direction. Thus “always kick right” or “always kick left” can’t be equilibrium strategies. Similarly, if the goalkeeper always dived in one direction, the player would be able to profitably deviate by kicking in the other. Thus the equilibrium strategy for the kicking player is to “mix it up” (use a mixed strategy) by kicking one way some of the time and the other way some of the time. Presuming the player selects randomly and doesn’t telegraph his moves, the goalkeeper can do no better than guessing. Therefore, the goalkeeper’s equilibrium response is to also mix it up, diving in each direction often enough to keep the kicker from exploiting his tendencies. This is why you often see wildly inaccurate dives: It’s not necessarily because they were faked out, it’s just that they picked scissors when the striker picked rock.

And, of course, the same principles apply in much more complicated scenarios, like run/pass balance in football. If teams pass too often, defenses will exploit it by keying against the pass. If defenses key against the pass too much, offenses will exploit it by running more. Indeed, a key insight of game theory is that how you balance the different options in an “optimal” (meaning equilibrium) strategy isn’t just a matter of how good each option seems in a vacuum; it matters how your opponent will adapt to your strategy overall.

 

The Athlete Sleep Screening Questionnaire: a new tool for assessing and managing sleep in elite athletes. – PubMed – NCBI

British Journal of Sports Medicine from May 22, 2015

BACKGROUND/AIM:
The purpose of this study was to develop a subjective, self-report, sleep-screening questionnaire for elite athletes. This paper describes the development of the Athlete Sleep Screening Questionnaire (ASSQ).
METHODS:
A convenience sample of 60 elite athletes was randomly distributed into two groups; 30 athletes completed a survey composed of current psychometric tools, and 30 athletes completed a revised survey and a sleep specialist structured clinical interview. An item analysis was performed on the revised survey with comparison to clinical decisions regarding appropriate intervention based on a sleep specialist assessment.
RESULTS:
A comparison of existing sleep-screening tools with determination of clinical need from a sleep specialist showed low consistency, indicating that current sleep-screening tools are unsuitable for assessing athlete sleep. A new 15-item tool was developed (ASSQ) by selecting items from existing tools that more closely associated with the sleep specialist’s reviews. Based on test-retest percentage agreement and the ?-statistic, we found good internal consistency and reliability of the ASSQ. To date, 349 athletes have been screened, and 46 (13.2%) identified as requiring follow-up consultation with a sleep specialist. Results from the follow-up consultations demonstrated that those athletes identified by the ASSQ as abnormal sleepers have required intervention.
CONCLUSIONS:
The research developed a new athlete-specific sleep-screening questionnaire. Our findings suggest that existing sleep-screening tools are unsuitable for assessing sleep in elite athletes. The ASSQ appears to be more accurate in assessing athlete sleep (based on comparison with expert clinical assessment). The ASSQ can be deployed online and provides clinical cut-off scores associated with specific clinical interventions to guide management of athletes’ sleep disturbance. The next phase of the research is to conduct a series of studies comparing results from the ASSQ to blinded clinical reviews and to data from objective sleep monitoring to further establish the validity of the ASSQ as a reliable sleep screening tool for elite athletes.

 

A simple method for measuring power, force, velocity properties, and mechanical effectiveness in sprint running – Samozino – 2015

Scandinavian Journal of Medicine & Science in Sports from May 21, 2015

This study aimed to validate a simple field method for determining force– and power–velocity relationships and mechanical effectiveness of force application during sprint running. The proposed method, based on an inverse dynamic approach applied to the body center of mass, estimates the step-averaged ground reaction forces in runner’s sagittal plane of motion during overground sprint acceleration from only anthropometric and spatiotemporal data. Force– and power–velocity relationships, the associated variables, and mechanical effectiveness were determined (a) on nine sprinters using both the proposed method and force plate measurements and (b) on six other sprinters using the proposed method during several consecutive trials to assess the inter-trial reliability. The low bias (<5%) and narrow limits of agreement between both methods for maximal horizontal force (638?±?84?N), velocity (10.5?±?0.74?m/s), and power output (1680?±?280?W); for the slope of the force–velocity relationships; and for the mechanical effectiveness of force application showed high concurrent validity of the proposed method. The low standard errors of measurements between trials (<5%) highlighted the high reliability of the method. These findings support the validity of the proposed simple method, convenient for field use, to determine power, force, velocity properties, and mechanical effectiveness in sprint running.

 

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