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I keep an open work document where I jot down quotes, articles, research, podcasts, and any other notes that I keep during the year. The following is this years collection of the above. You can find last years review - HERE Enjoy!
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Quotes/Thoughts
Articles
Podcasts
Research Harper DJ, Kiely J. Damaging nature of decelerations: Do we adequately prepare players? BMJ Open Sport & Exercise Medicine. 2018; 4 :e000379. Doi: 10.1136/bmjsem-2018-000379 :
Wild, J. J., Bezodis, I. N., North, J. S., & Bezodis, N. E. (2018). Differences in step characteristics and linear kinematics between rugby players and sprinters during initial sprint acceleration. European journal of sport science, 1-11.
Simperingham, K. D., Cronin, J. B., & Ross, A. (2016). Advances in sprint acceleration profiling for field-based team-sport athletes: Utility, reliability, validity and limitations. Sports Medicine, 46(11), 1619-1645.
Cross, M. R., Lahti, J., Brown, S. R., Chedati, M., Jimenez-Reyes, P., Samozino, P., & Morin, J. B. (2018). Training at maximal power in resisted sprinting: Optimal load determination methodology and pilot results in team sport athletes. PloS one, 13(4), e0195477.
Silva, P., Garganta, J., Araújo, D., Davids, K., & Aguiar, P. (2013). Shared knowledge or shared affordances? Insights from an ecological dynamics approach to team coordination in sports. Sports Medicine, 43(9), 765-772.
Matute, H., Cubillas, C. P., & Garaizar, P. (2017). Learning to infer the time of our actions and decisions from their consequences. Consciousness and cognition, 56, 37-49.
Broatch, J. R., Petersen, A., & Bishop, D. J. (2018). The Influence of Post-Exercise Cold-Water Immersion on Adaptive Responses to Exercise: A Review of the Literature. Sports Medicine, 1-19.
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The present findings suggest that CODS and RA are 2 different and independent skill domains that define agility. These qualities should be diagnosed by discrete assessments and enhanced by different training methodologies.
Soccer [n = 15 male] and rugby [n = 21; 9 male and 12 female] club-level athletes were individually assessed for horizontal force-velocity and load-velocity profiles using a battery of resisted sprints, sled or robotic resistance respectively. Athletes then performed a 12-session resisted sprint (10x20m) intervention with either a) load that represented maximum power output or b) load that represented a 10% decrease in maximal unresisted sprinting velocity. Both protocols had minor effects on sprinting performance (average of -1.4 to -2.3% split-times respectively), and provided trivial, small and unclear changes in mechanical sprinting parameters. Both resisted-sprint training protocols were likely to improve performance after a short training intervention in already sprint trained athletes. However, widely varied individualised results indicated that adaptations may be dependent on pre-training force-velocity characteristics
The initial steps of a sprint are important in team sports, such as rugby, where there is an inherent requirement to maximally accelerate over short distances. Current understanding of sprint acceleration technique is primarily based on data from track and field sprinters, although whether this information is transferable to athletes such as rugby players is unclear, due to differing ecological constraints. Sagittal plane video data were collected (240 Hz) and manually digitised to calculate the kinematics of professional rugby forwards (n = 15) and backs (n = 15), and sprinters (n = 18; 100 m personal best range = 9.96-11.33 s) during the first three steps of three maximal sprint accelerations. Using a between-group research design, differences between groups were determined using magnitude-based inferences, and within-group relationships between technique variables and initial sprint acceleration performance were established using correlation. Substantial between-group differences were observed in multiple variables. Only one variable, toe-off distance, differed between groups (d = -0.42 to -2.62) and also demonstrated meaningful relationships with sprint performance within all three groups (r = -0.44 to -0.58), whereby a stance foot position more posterior relative to the centre of mass at toe-off was associated with better sprint performance. While toe-off distance appears to be an important technical feature for sprint acceleration performance in both sprinters and rugby players, caution should be applied to the direct transfer of other kinematic information from sprinters to inform the technical development of acceleration in team sports athletes.
The primary purpose of this study was to determine if a difference existed between peak speed attained when performing a sprint with maximal acceleration versus from a gradual build-up. Additionally, this investigation sought to compare the actual peak speed achieved when instructed to reach 75% and 90% of maximum speed. Field sport athletes (n = 21) performed sprints over 60 m under the experimental conditions, and the peak speed was assessed with a radar gun. The gradual build-up to maximum speed (8.30 ± 0.40 m·s −1 ) produced the greater peak speed (effect size = 0.3, small) than the maximum acceleration run (8.18 ± 0.40 m·s −1 ), and the majority of participants (62%) followed this pattern. For the sub-maximum runs, the actual mean percentage of maximum speed reached was 78 ± 6% for the 75% prescribed run and 89 ± 5% for the 90% prescription. The errors in attaining the prescribed peak speeds were large (~15%) for certain individuals, especially for the 75% trial. Sprint training for maximum speed should be performed with a gradual build-up of speed rather than a maximum acceleration. For sub-maximum interval training, the ability to attain the prescribed target peak speed can be challenging for field sport athletes, and therefore where possible, feedback on peak speeds reached should be provided after each repetition.
Sleep deprivation of 5-days (6.5hrs) vs healthy sleep opportunity (9.5hrs) in 14-18 y.o’s showed significantly worse symptoms of Post Concussion Assessment and Cognitive Testing. Verbal memory also decreased. Concluding that sleep deprivation of just 5-days increases concussion like symptoms and that sleep deprivation has adverse effects on emotional and behavioral functioning in teens.
Research shows that people infer the time of their actions and decisions from their consequences. We asked how people know how much time to subtract from consequences in order to infer their actions and decisions. They could either subtract a fixed, default, time from consequences, or learn from experience how much time to subtract in each situation. In two experiments, participants’ actions were followed by a tone, which was presented either immediately or after a delay. In Experiment 1, participants estimated the time of their actions; in Experiment 2, the time of their decisions to act. Both actions and decisions were judged to occur sooner or later as a function of whether consequences were immediate or delayed. Estimations tended to be shifted toward their consequences, but in some cases they were shifted away from them. Most importantly, in all cases participants learned progressively to adjust their estimations with experience.
Post-exercise cold-water immersion (CWI) is used extensively in exercise training as a means to minimise fatigue and expedite recovery between sessions. However, debate exists around its merit in long-term training regimens. While an improvement in recovery following a single session of exercise may improve subsequent training quality and stimulus, reports have emerged suggesting CWI may attenuate long-term adaptations to exercise training. Recent developments in the understanding of the molecular mechanisms governing the adaptive response to exercise in human skeletal muscle have provided potential mechanistic insight into the effects of CWI on training adaptations. Preliminary evidence suggests that CWI may blunt resistance signalling pathways following a single exercise session, as well as attenuate key long-term resistance training adaptations such as strength and muscle mass. Conversely, CWI may augment endurance signaling pathways and the expression of genes key to mitochondrial biogenesis following a single endurance exercise session, but have little to no effect on the content of proteins key to mitochondrial biogenesis following long-term endurance training. This review explores current evidence regarding the underlying molecular mechanisms by which CWI may alter cellular signaling and the long-term adaptive response to exercise in human skeletal muscle.
The aim of this study was to investigate spatiotemporal and kinematic changes between the initial acceleration, transition and maximum velocity phases of a sprint. Sagittal plane kinematics from five experienced sprinters performing 50-m maximal sprints were collected using six HD-video cameras. Following manual digitising, spatiotemporal and kinematic variables at touchdown and toe-off were calculated. The start and end of the transition phase were identified using the step-to-step changes in centre of mass height and segment angles. Mean step-to-step changes of spatiotemporal and kinematic variables during each phase were calculated. Firstly, the study showed that if sufficient trials are available, step-to-step changes in shank and trunk angles might provide an appropriate measure to detect sprint phases in applied settings. However, given that changes in centre of mass height represent a more holistic measure, this was used to sub-divide the sprints into separate phases. Secondly, during the initial acceleration phase large step-to-step changes in touchdown kinematics were observed compared to the transition phase. At toe-off, step-to-step kinematic changes were consistent across the initial acceleration and transition phases before plateauing during the maximal velocity phase. These results provide coaches and practitioners with valuable insights into key differences between phases in maximal sprinting.
The ability to detect deceptive movement was examined in skilled and novice rugby players. Participants (14 per group) attempted to predict direction change from video of expert and recreational rugby players changing direction with and without deceptive movement. ConWdence associated with judgments was recorded on each trial to seek evidence regarding use of inferential (heuristic-based) and direct-perceptual (invariant-based) judgments. Novices were found to be susceptible to deceptive movement whereas skilled participants were not; however, both skilled and novice participants were more conWdent on trials containing deceptive movement. The data suggest that the skill-level diVerence in sensitivity to advance visual information extends to deceptive information. The implications of this Wnding, and the importance of considering the underlying process of anticipation skill, are discussed. Random
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Research Amiri, M., Ghiasvand, R., Kaviani, M., Forbes, S. C., & Salehi-Abargouei, A. (2018). Chocolate milk for recovery from exercise: a systematic review and meta-analysis of controlled clinical trials. European Journal of Clinical Nutrition, 1.
Moras, G., Fernández-Valdés, B., Vázquez-Guerrero, J., Tous-Fajardo, J., Exel, J., & Sampaio, J. (2018). Entropy measures detect increased movement variability in resistance training when elite rugby players use the ball. Journal of science and medicine in sport.
Almonroeder, T. G., Tighe, S. M., Miller, T. M., & Lanning, C. R. (2018). The influence of fatigue on decision-making in athletes: a systematic review. Sports biomechanics, 1-14.
Strafford, B. W., Van Der Steen, P., Davids, K., & Stone, J. A. (2018). Parkour as a donor sport for athletic development in youth team sports: insights through an ecological dynamics lens. Sports medicine-open, 4(1), 21.
Folland, J. P., Allen, S. J., Black, M. I., Handsaker, J. C., & Forrester, S. E. (2017). Running technique is an important component of running economy and performance. Medicine and science in sports and exercise, 49(7), 1412.
Almonroeder, T. G., Tighe, S. M., Miller, T. M., & Lanning, C. R. (2018). The influence of fatigue on decision-making in athletes: a systematic review. Sports biomechanics, 1-14.
Jackson, R. C., Warren, S., & Abernethy, B. (2006). Anticipation skill and susceptibility to deceptive movement. Acta psychologica, 123(3), 355-371.
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The aim of this study was to examine the physical performance of a success-Serie A team of more than three consecutive seasons. 25 players participated in the study and were classified into three playing positions: defenders (n=9), midfielders (n=11) and forward (n=5). Activities match were studied by an analysis of multiple match-camera SICS ® (Bassano del Grappa, Italy) throughout the competition Italian Serie A matches played at home (n=90) for 3 consecutive seasons (first: 2004/2005, second: 2005/2006, and third: 2006/2007). Total team ball possession and time-motion characteristics were examined. Results showed that total ball possession (52.1% to 54.9%) and the number of points accumulated at home (40/48) improved in the past three seasons while that the final ranking at home were stable. The total distances covered by minutes of play were significantly different between the three seasons (118.32±6.69m.min to 111.96±8.05m.min). Distance running and high intensity activities were similar in the three seasons, while the distance covered in moderate intensity running decreased in the third (P<0.05). Variations between playing positions were found during the three-consecutive seasons, with midfielders covering greater distances than defenders (P<0.05) and forward (P<0.01). This study showed how for three consecutive seasons of successful players Serie-A team reduced their distances performed at submaximal speeds, and increased ball possession, while maintaining the high-intensity activities and the number of points at home. It is suggested that this is due to a better understanding of roles and tactics team organization, and to act collectively and individually on these parameters to reduce energy expenditure during the game to maintain a high level performance throughout the season.
Most change of direction biomechanical investigations and current technique guidelines focus on the role of the final foot contact (plant foot contact). However, it is evident that the braking characteristics during the penultimate foot contact play an integral role in deceleration prior to directional changes ≥ 60˚; and can therefore, be described as a “preparatory step”. In this review, we examine the role of the penultimate foot contact on change of direction performance and associated biomechanical injury risk factors, and provide technical guidelines for coaching the “preparatory step” during change of direction, to enhance performance and reduce risk of injury.
A meta-analysis of 13 studies with a total of 18 effect sizes was performed to analyse the role of various factors on the effectiveness of flywheel paradigm training. The following inclusion criteria were employed for the analysis: (a) randomized studies; (b) high validity and reliability instruments; (c) published in a high quality peer-reviewed journal; (d) healthy participants; (e) studies where the eccentric programme were described; and (f) studies where increases in muscle volume and force were measured before and after training. Increases in muscle volume and force were noted through the use of flywheel systems during short periods of training. The increase in muscle mass appears was not influenced by the existence of eccentric overload during the exercise. The increase in force was significantly higher with the existence of eccentric overload during the exercise. The responses identified in this analysis are essential and should be considered by strength and conditioning professionals regarding the most appropriate dose response trends for flywheel paradigm systems to optimize the increase in muscle volume and force
examine existing theories and approaches that try to explain the process of skill acquisition so as to determine implications of these theories for instructional provision. This is followed by an evaluation of studies in the motor learning literature in which pre-practice information has been manipulated. Explicit learning strategies are contrasted to implicit and discovery learning methods, and current explanations for instructional eþects are discussed in terms of such mechanisms as eþects-related attentional focus and movement variability. In the ®nal sections, we review data from our own laboratory where pre-practice information has been manipulated during the learning of a novel bimanual coordination task. From these studies, proposals are made to try and explain how pre-practice information works to eþect the process of skill acquisition, including the selection and execution of a response and the processing of associated feedback. An important role is given to the existing skills of the learner in understanding the instructions and performing the desired movement. Finally, we suggest some practical implications of this empirical evidence for the teaching of motor skills.
The application of match specific constraints in resistance training for rugby players elicit different amount of variability of body acceleration across multiple physiological time scales. Understanding the non-linear process inherent to the manipulation of resistance training variables with constraints and its motor adaptations may help coaches and trainers to enhance the effectiveness of physical training and, ultimately, better understand and maximize sports performance.
The purpose of the current study was to develop an understanding of visual search behaviour in relation to performance outcome amongst elite level youth soccer players, within competitive match performance. Thirteen matches from an English Premier League academy soccer team (under 15 age group) were analysed using a specifically designed notational analysis system created in Microsoft Excel. Visual explorations conducted by individual players were collated, followed by their subsequent action when in possession of the ball. The results show significant visual exploration differences between higher and lower ability elite level youth players (p=0.000). The results of a series of categorical logistic regression analyses also show a clear positive relationship exists between visual exploratory behaviours that are initiated prior to a player receiving the ball and performance with the ball. This relationship remains when assessed amongst several match conditions including overall pass completion, attacking third pass completion and forward pass completion.
The general purpose of this study was to examine how soccer defenders explore the environment for and use the information to deny opponents goals from crosses into the penalty area. A specific aim was to determine which variables differentiated between elite and sub-elite players. An ecological approach was used as conceptual framework. Participants were at the Premier League level - classified as elite (n = 13, m = 28.15 yrs, SD = 3.82) and at the Reserve League and Academy League level - classified as sub-elite (n = 11, m = 18.3 yrs, SD = 1.40). All participants were filmed in at least one game (six were filmed in two game). A high zoom camera recorded and focused solely upon a single player and general game events were obtained from professional camera recordings (obtained from the clubs) using regular zoom. These two videos were edited and synchronized into a split-screen video. Results indicate that players in the elite group are more perceptually and functionally active than players in the sub-elite group prior to a cross, by exploring more frequently and positioning themselves more with a back-towards-goal posture allowing them to visually perceive more of the actions of the surrounding forwards. However, it was not demonstrated any functional relationship between exportation and performance related to this defensive situation. Further, constraints such as the player’s posture, type of defense, distance be-tween the crosser and defender, and involvement showed some differences between the levels and may affect exploration.
In this paper we propose that the term skill acquisition, as commonly used in traditional psychology, and the philosophy, education, movement science and performance development literatures, has been biased by an organismic asymmetry. In cognitive and experimental psychology, for example, it refers to the establishment of an internal state or representation of an act which is believed to be acquired as a result of learning and task experience. Here we elucidate an ecological perspective which suggests that the term skill acquisition may not refer to an entity but rather to the emergence of an adaptive, functional relationship between an organism and its environment, thus avoiding an inherent organismic asymmetry in theorizing. In this respect, the terms 'skill adaptation' or 'skill attunement' might be more suitable to describe this process.
The ecological dynamics approach offers new insights to understand how athlete nervous systems are embedded within the body–environment system in sport. Cognitive neuroscience focuses on the neural bases of athlete behaviors in terms of perceptual, cognitive, and motor functions defined within specific brain structures. Here, we discuss some limitations of this traditional perspective, addressing how athletes functionally adapt perception and action to the dynamics of complex performance environments by continuously perceiving information to regulate goal-directed actions. We examine how recent neurophysiological evidence of functioning in diverse cortical and subcortical regions appears more compatible with an ecological dynamics perspective, than traditional views in cognitive neuroscience. We propose how athlete behaviors in sports may be related to the tuning of resonant mechanisms indicating that perception is a dynamic process involving the whole body of the athlete. We emphasize the important role of metastable dynamics in the brain–body–environment system facilitating continuous interactions with a landscape of affordances (opportunities for action) in a performance environment. We discuss implications of these ideas for performance preparation and practice design in sport.
The aim of the present study was to compare (a) the maximal sprinting speed (MSS) attained by soccer players during matches (MSSmatch) according to their level of play (professional first French division vs. elite amateur fourth French division) and the playing positions and (b) the MSS attained by professional soccer players during 14 different types of small-sided games (SSG, MSSSSG) and match-play. All players monitored through the study performed a 40-m sprint test to assess individual MSS (MSStest) and compare it to the training and match activity, with the calculation of the percentage of MSStest (%MSStest) reached. No differences were found according to the level of play; however, positional wide players achieved a higher MSSmatch, %MSStest, and MSSSSG than central players (both defenders and midfielders) during matches and SSG. MSSmatch were higher than all MSSSSG, and MSSSSG were positively correlated with the area of the pitch (0.45, p < 0.001), its length (0.53,p < 0.001), and the number of players involved (0.38, p < 0.001). The closer SSG was to match situation in terms of rules, the higher the MSSSSG. Wide players reached higher MSS in match and SSG than central players, confirming the relevance of using SSG close to match situation to specifically prepare elite players to the maximal running speed demand of the match.
American football is played in a chaotic visual environment filled with relevant and distracting information. We investigated the hypothesis that collegiate football players show exceptional skill at shielding their response execution from the interfering effects of distraction (interference control). The performances of 280 football players from National Collegiate Athletic Association Division I football programs were compared to age-matched controls in a variant of the Eriksen flanker task (Eriksen and Eriksen, 1974). This task quantifies the magnitude of interference produced by visual distraction on split-second response execution. Overall, football athletes and age controls showed similar mean reaction times (RTs) and accuracy rates. However, football athletes were more proficient at shielding their response execution speed from the interfering effects of distraction (i.e., smaller flanker effect costs on RT). Offensive and defensive players showed smaller interference costs compared to controls, but defensive players showed the smallest costs. All defensive positions and one offensive position showed statistically smaller interference effects when compared directly to age controls. These data reveal a clear cognitive advantage among football athletes at executing motor responses in the face of distraction, the existence and magnitude of which vary by position. Individual differences in cognitive control may have important implications for both player selection and development to improve interference control capabilities during play.
Since the middle of the nineteenth century, movement scientists have been challenged to explain processes underlying the control, coordination, and acquisition of skill. Information processing and constraints-based approaches represent two distinct, often perceived as opposing, views of skill acquisition. The purpose of this article is to compare information processing and constraints-based approaches through the lens of Fitts’ three-stage model and Newell’s constraints-based model, respectively. In essence, both models can be identified, at least in spirit, with ideas about skill described by Bernstein (1967, 1996). Given that the product of “skill acquisition” is the same, although the explanation of the processes might differ, it is perhaps not surprising that similarities between the models appear greater than the differences. In continuing to meet the challenge to explain skill acquisition, neural-based models provide a glimpse of the cutting edge where behavior and biological mechanisms underpinning processes of control, coordination, and acquisition of skill might meet. Books I’ve always enjoyed Coyle’s books, starting with the Talent Code – actually did an interview with him you can find here – https://www.building-better-athlete.com/blog/interview-with-daniel-coyle He does a fantastic job of story telling, bring ideas together, and mixing science with culture. Some of his writings may be a little exaggerated with what the actual literature says, but its much less taken out of context as say Malcolm Gladwell. Some of my favorite tidbits…
Personally I find these kinds of books a little cheesy, but it’s a quick, painless read with a few tidbits here and there. Good book to throw into the mixture of more serious reads - with short chapters and some good reminders but too much of Gordon’s self-help message gets old, fast. 2-3 Gordon books a year is plenty This was a fascinating read into 10 of the greatest psychological experiments over the past 100-years. From BF Skinner to Harry Harlow to Eric Kandel to Stanley Milgram. From topics such as love to obedience to addiction to false memories. With subjects from humans undergoing lobotomy’s, monkeys separated from their mothers and having a surrogate mother, rats being rewarded with food and drugs, sea slugs and memory. Slater does an incredible job of blending the hard-nosed details of the experiments and outcomes, to laying out a story line of each researcher, their backgrounds into their studies, and personal stories of how these scientists affect her and other psychologists. Give this one a read!    Thoughts/Quotes
A Note on Sport Specialization This past weekend was the NFL Draft, and as this weekend arrives every year, so do the cries from people with daily stats on how may NFL draftees played multiple sports, quotes of college coaches saying they recruit multi-sport athletes, and the claim playing multiple sports is key in them getting drafted. A HUGE discussion was brought out by Keir Wenham-Flatt with this tweet – I encourage you to read all the branches this tweet spurred I want to share my thoughts on this topic, as it seems I've been booked into promoting specialization by some coaches because I disagree with their commentary and language used. In today's world, having an opinion that differs from the majority gets you yelled at, called an idiot, or the worse of all... blocked on twitter. In fact, Tony Holler, a coach I highly respect and enjoy his work, blocked me because I disagreed with his opinion on this topic, and instead of having an intelligent discourse, he blocked me and proceeded to tweet negative things about me... heartbreaking So, here are some random thoughts on specialization 1. First I want to make it clear, I don’t think anyone is truly pushing specialization - in the terms that specialization actually exists. THIS is where I think many of these coaches go wrong – if they’d actually read the literature on specialization, they’d know that it points to NOT specializing at young ages (7-13), and instead to get involved in many athletic endeavors – and this is something I don’t think anyone is disputing. Again if you’ve read the literature, it actually points to encouraging specialization around ages 16-18 – well guess what – That’s a sophomore through senior in HS. So if a HS kid is passionate about a sport and wants maximize his/her ability in that sport – the literature actually supports this decision. So, that’s the difference – when to specialize, NOT if specializing is bad. I think we all agree 7-12 year olds should be exposed to as many athletic events as possible. Understand that a 7-12 year old specializing is vastly different than a 16-18 year old specializing. 2. Let's Try an Example We have Johnny and Billy - both are HS Juniors. Johnny was blessed with the genetic lottery - He’s a very gifted athlete. Football is his primary sport, with a scholarship on the way. He also plays basketball and track. Johnny is a 9/10 football player, and even though he only plays basketball during the season (3-months out of the year), he still manages to be a 7/10 basketball player because of his raw athletic ability. Physically dominant kids like Johnny can afford to be less technically & tactically skilled in their lesser sports and still be good – hence why he is a 7/10 with only playing basketball 3-months out of the year. And remember - When you're a good athlete you get pulled into multiple sports. It's not that playing multiple sports causes one to become a good athlete - it's being a good athlete causes one to be pulled to play multiple sports. Billy on the other hand was not blessed with superior genetics, he's a pretty average athlete. Billy loves basketball; it’s his passion and his ultimate goal is to play college basketball - ultimately he realizes DI is out of the question and DIII is his likely route - but that shouldn't be any less of a reason to pursue this goal. Unfortunately for Billy, he’s only a 6/10 basketball player. So, how can Billy compete with Johnny in basketball??? Well, Billy decides to specialize in basketball. He improves his basketball specific skill set, IQ, specific perception, and learns the nuances of the game that can only come from accumulating time in that sport. Basketball season comes around and now Billy is a 7/10 – he now has a chance to compete with Johnny. If he played multiple sports, he’d still be a 6/10 and wouldn’t see the court. By his senior year, Billy has raised himself to a 7.5/10 basketball player, good enough to be a starter and earn an opportunity to play at the DIII level. Who is to say this is the wrong path for Billy? I can hear the critics – But he’ll burnout, that doesn’t sound fun, he’ll never be as athletic if he played multiple sports, etc. But I ask – who led this situation? It was athlete led; Billy decided this is what HE wanted, and it is wrong for an adult to criticize his decision – and this is where I get frustrated. 3. The language I see used by coaches needs to change. Athletes NEED to run track; they MUST play basketball; they HAVE to play baseball. If you're under 6'6 and don't have a basketball scholarship yet - you NEED to be playing football (these are real quotes from coaches - publicly displayed on Twitter) Ever thought for a second that the athlete just doesn’t like those sports? That they don't like track or football or any other sport? My argument is how is this any better than the AAU coach saying the same thing? We get pissed if an AAU coach says - If you want to play college basketball you NEED to play AAU. If you want to get noticed by college coaches you HAVE to play AAU. It’s the same thing – it’s an adult with an agenda trying to lead the decision. Athletes should be encouraged to play multiple sports – no doubt. But coaches shouldn’t FORCE or MAKE HS athletes play multiple sports. If a kid doesn’t like a sport, stop trying to push them to do it. A who cares if a kid wants to play hoops all year long, and they’re only 5’11 – if it’s athlete led and the kids passion – awesome. 4. If a HS kid can start to specialize his/her education, then why not sports? Junior and senior HS kids are asked what careers they’d like to pursue and encouraged to specialize their schoolwork towards those careers. My junior and senior year, I don’t think I took an English class; instead I loaded up my schedule in the math and sciences because that’s what I enjoyed. Why is it different for sports? Or how about this - why don't college or professional athletes play multiple sports? If playing multiple sports is the panacea of athletic development - why don't athletes post HS do it? 5. What classifies as playing multiple sports? I have a number of Jr. & Sr. football players who don’t play another sport but play pick-up basketball 2-3 days a week. I have college basketball players that golf 2-3 days a week. Does playing a wide variety of games in the backyard as a youngster count multiple sports? Does this negate specialization? 6. A final piece and hardest for people to come to terms with – Specialization works! When done right, specializing has worked for tons of athletes all over the world. Look at sports like gymnastics, swimming/diving, tennis, soccer, golf, basketball, baseball - the majority of the athletes in these sports have specialized from a young age. Look at countries who send little kids to specialized camps from a young age to groom them into Olympians. Specialization works. 7. Clearly it is much more complex than specialization = bad multiple sports = good. And that’s how this whole thing got started – coaches with an agenda (yes I said agenda) trying to get better athletes to play their sport. At the end of the day kids should define their own athletic experience. Trust me, I played 3 sports in HS and couldn’t imagine only playing a single sport in HS – but I also understand everybody is different and kids should lead the decision-making process. Ok, enough of this rant... on to normal business Articles
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A novel approach of analysing complete ground reaction force waveforms rather than discrete kinetic variables can provide new insight to sprint biomechanics. This study aimed to understand how these waveforms are associated with better performance across entire sprint accelerations. Twenty-eight male track and field athletes (100-m personal best times: 10.88 to 11.96 s) volunteered to participate. Ground reaction forces produced across 24 steps were captured during repeated (two to five) maximal-effort sprints utilising a 54-force-plate system. Force data (anteroposterior, vertical, resultant and ratio of forces) across each contact were registered to 100% of stance and averaged for each athlete. Statistical parametric mapping (linear regression) revealed specific phases of stance where force was associated with average horizontal external power produced during that contact. Initially, anteroposterior force production during mid-late propulsion (e.g. 58-92% of stance for the second ground contact) was positively associated with average horizontal external power. As athletes progressed through acceleration, this positive association with performance shifted towards the earlier phases of contact (e.g. 55-80% of stance for the eighth and 17-57% for the 19th ground contact). Consequently, as athletes approached maximum velocity, better athletes were more capable of attenuating the braking forces, especially in the latter parts of the eccentric phase. These unique findings demonstrate a shift in the performance determinants of acceleration from higher concentric propulsion to lower eccentric braking forces as velocity increases. This highlights the broad kinetic requirements of sprinting and the conceivable need for athletes to target improvements in different phases separately with demand-specific exercises.
Previous perceptual-cognitive skill research in sport has often applied laboratory-based protocols to examine differences amongst elite and sub-elite performers. Contemporary research within the area has started to move away from such protocols and has begun analysing visual search behaviours within competitive adult soccer matches. The purpose of the current study was to develop an understanding of visual search behaviour in relation to performance outcome amongst elite level youth soccer players, within competitive match performance. Thirteen matches from an English Premier League academy soccer team (under 15 age group) were analysed using a specifically designed notational analysis system created in Microsoft Excel. Visual explorations conducted by individual players were collated, followed by their subsequent action when in possession of the ball. The results show significant visual exploration differences between higher and lower ability elite level youth players (p=0.000). The results of a series of categorical logistic regression analyses also show a clear positive relationship exists between visual exploratory behaviours that are initiated prior to a player receiving the ball and performance with the ball. This relationship remains when assessed amongst several match conditions including overall pass completion, attacking third pass completion and forward pass completion
The general purpose of this study was to examine how soccer defenders explore the environment for and use the information to deny opponents goals from crosses into the penalty area. A specific aim was to determine which variables differentiated between elite and sub-elite players. An ecological approach was used as conceptual framework. Participants were at the Premier League level - classified as elite (n = 13, m = 28.15 yrs, SD = 3.82) and at the Reserve League and Academy League level - classified as sub-elite (n = 11, m = 18.3 yrs, SD = 1.40). All participants were filmed in at least one game (six were filmed in two game). A high zoom camera recorded and focused solely upon a single player and general game events were obtained from professional camera recordings (obtained from the clubs) using regular zoom. These two videos were edited and synchronized into a split-screen video. Results indicate that players in the elite group are more perceptually and functionally active than players in the sub-elite group prior to a cross, by exploring more frequently and positioning themselves more with a back-towards-goal posture allowing them to visually perceive more of the actions of the surrounding forwards. However, it was not demonstrated any functional relationship between exportation and performance related to this defensive situation. Further, constraints such as the players posture, type of defense, distance be-tween the crosser and defender, and involvement showed some differences between the levels and may affect exploration.
Using a crossover design, eighteen soccer athletes performed 5 m, 10 m, and 20 m sprints before and 15 s, 4 min, and 8 min after two PAP protocols. The PAP conditioning activities consisted of hip thrust exercises loaded with either 85% 1RM or a load for optimum power development. The resulting 5 m and 10 m sprint performances were impaired at 15 s following both protocols. At 4 min and 8 min, meaningful improvements were observed for the three sprint distances following both of the protocols. Meaningful differences were found when comparing the two PAPs over time: greater impairments in 5 m and 10 m following the 85% of 1 RM protocol after 15 s, and greater improvements in all sprint distances after 4 min and 8 min following the optimum power development protocol. Positive correlations between the hip thrust's 1RM and power values and the overall individual PAP responses were found. This investigation showed that both heavy-loaded and optimum-power hip thrust exercises can induce a PAP response, with the optimum-power development protocol preferred due its higher efficiency.
A review of Van Hooren and Bosch article that argues isometric exercises may be more effective at reducing hamstrings injuries and more easily and smartly programmed into busy training schedules than eccentric exercises.
Van Hooren and Bosch respond to the questions and comments posed by Shield and Murphy in part 1
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Research Tsoukos, A., Veligekas, P., Brown, L. E., Terzis, G., & Bogdanis, G. C. (2018). Delayed Effects of a Low-Volume, Power-Type Resistance Exercise Session on Explosive Performance. The Journal of Strength & Conditioning Research, 32(3), 643-650.
Araujo, D., Davids, K., & Hristovski, R. (2006). The ecological dynamics of decision making in sport. Psychology of sport and exercise, 7(6), 653-676.
Bruce, L., Farrow, D., Raynor, A., & Mann, D. (2012). But I can’t pass that far! The influence of motor skill on decision making. Psychology of Sport and Exercise, 13(2), 152-161.
Liefeith, A., Kiely, J., Collins, D., & Richards, J. (2018). Back to the Future–in support of a renewed emphasis on generic agility training within sports-specific developmental pathways.Journal of sports sciences, 1-6.
Buckner, S. L., Jessee, M. B., Dankel, S. J., Mattocks, K. T., Abe, T., & Loenneke, J. P. (2018). Resistance exercise and sports performance: The minority report. Medical hypotheses,113, 1-5.
Jeffreys, I., Huggins, S., & Davies, N. (2018). Delivering a Gamespeed-focused Speed and Agility Development Program in an English Premier League Soccer Academy. Strength & Conditioning Journal.
Warren, C. D., Brown, L. E., Landers, M. R., & Stahura, K. A. (2011). Effect of three different between-inning recovery methods on baseball pitching performance. The Journal of Strength & Conditioning Research, 25(3), 683-688.
Warren, C. D., Brown, L. E., Landers, M. R., & Stahura, K. A. (2011). Effect of three different between-inning recovery methods on baseball pitching performance. The Journal of Strength & Conditioning Research, 25(3), 683-688.
Nagahara, R., Takai, Y., Haramura, M., Mizutani, M., Matsuo, A., Kanehisa, H., & Fukunaga, T. (2018). Age-Related Differences in Spatiotemporal Variables and Ground Reaction Forces During Sprinting in Boys. Pediatric exercise science,20(XX), 1-10.
Sugisaki, N., Kobayashi, K., Tsuchie, H., & Kanehisa, H. (2017). Associations Between Individual Lower Limb Muscle Volumes and 100-m Sprint Time in Male Sprinters.International journal of sports physiology and performance, 1-19.
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This data reveals a clear cognitive advantage among football athletes at executing motor responses in the face of distraction, the existence and magnitude of which vary by position. Individual differences in cognitive control may have important implications for both player selection and development to improve interference control capabilities during play.
Individual differences in 100-m-race performance cannot be explained by the muscularity of specific muscles, and 23% of the variability in the performance can be explained by the relative difference between the muscularity of gluteus maximus and quadriceps femoris; faster runners have a greater gluteus maximus relative to quadriceps femoris.
Participants (14 per group) attempted to predict direction change from video of expert and recreational rugby players changing direction with and without deceptive movement. Confidence associated with judgments was recorded on each trial to seek evidence regarding use of inferential (heuristic-based) and direct-perceptual (invariant-based) judgments. Novices were found to be susceptible to deceptive movement whereas skilled participants were not; however, both skilled and novice participants were more confident on trials containing deceptive movement. The data suggest that the skill-level difference in sensitivity to advance visual information extends to deceptive information. The implications of this finding, and the importance of considering the underlying process of anticipation skill.
Although there is a large body of cross-sectional literature providing a rationale for resistance exercise for sport, its implementation is largely based on the following: 1) An increase in muscle size will produce an increase in strength and 2) a stronger muscle will increase sports performance. However, there is a lack of evidence to support these assumptions. The weight of evidence suggests that resistance exercise may indirectly impact sports performance through injury prevention, as opposed to directly improving sport related abilities.
The effectiveness of resistance training methods on sprinting performance is not always demonstrated experimentally. Accelerative sprinting is limited by the the requirement of a foreward-directed ground reaction force during progressively shorter stance phases that accompany higher sprinting speeds, whereas maximal speed sprinting is limited by the application of sufficient vertical impulse during stance, constraining minimal stance durations. Considering the mechanical limitations and the biomechanical solutions used by the fastest sprinters from a constraints-led perspective provides a framework from which practitioners can explore the incorporation of resistance and sprint training in the development of long-term training programs.
While there was a significant main effect of training for both groups, no statistically significant between-group differences were found (p ≥ 0.17) for any of the dependent variables. However, medium effect sizes in favor of the jump-squat training group were seen in SJ height (d = 0.56) and SJ peak power (d = 0.69). Loaded jumps seem equally effective as weightlifting derivatives for improving lower-body power in experienced athletes. Since loaded jumps require less skill and less coaching expertise than weightlifting, loaded jumps should be considered where coaching complex movements is difficult.
Driven by recent empirical studies, we offer a new understanding of the degrees of freedom problem, and propose a refined concept of synergy as a neural organization that ensures a one-to-many mapping of variables providing for both stability of important performance variables and flexibility of motor patterns to deal with possible perturbations and/or secondary tasks. Empirical evidence is reviewed, including a discussion of the operationalization of stability/flexibility through the method of the uncontrolled manifold. We show how this concept establishes links between the various accounts for how movement is organized in redundant effector systems.
A total of 449 participants met the inclusion criteria. Of all respondents, 252 athletes (56.1%) sustained an injury in the preceding 12 months. The most injured body parts were the shoulder (n = 87, 28.7%), lower back (n = 48, 15.8%), and knee (n = 25, 8.3%). The duration of participation in CrossFit significantly affected the injury incidence rates (<6 months vs ≥24 months; odds ratio, 3.687 [95% CI, 2.091-6.502]; P < .001). The majority of injuries were caused by overuse (n = 148, 58.7%). Books Been a slow month for reading books, only managed a measly one News
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This paper explores the effects of practice conditions on motor learning, specifically looking at contextual interference and knowledge of results. Learning is related to information arising from performance, which should be prioritized during training/practice. The challenge point hypothesis is presented.
The warm-up for high level athletes needs to seen as more than just general ie raising body temperature, preparing tissues, increasing CNS – but rather as a chance to recalibrate fine motor skills
We all know that eliminating non-desirable behaviors can be difficult, even when there is a clear understanding that poor habits are detrimental. Athletes often know the benefits of diet, exercise, and drinking less alcohol, yet short-term bursts of enthusiasm are more common than long-term change. Academics in behavior change consistently report that efforts to change health behaviors, such as the ones mentioned, have had limited success. Experienced coaches and sport scientists often represent the “front line” when it comes to promoting changes in an athlete’s behavior and positive habits. Unfortunately, change is often difficult; some athletes will resist change, as the effort required to change poor behaviors may not always seem to be worth it. Or, perhaps fear of the outcome stifles initiation and following through with desired changes. Trying to get athletes to sleep more is a common example of trying to modify behavior to improve performance. Many will agree that sleep is a pleasant activity. Additionally, sleep researchers have revealed many benefits of consistent sleep for the athlete. The fact that most individuals actually like to sleep and complain when they do not get enough sleep suggests that it should not be difficult to get athletes to improve sleep behavior. However, athletes often obtain well below the general recommendation of 8 hours of sleep per night. Potentially one of the hardest things to change is the use of electronic devices before bed. How do we get our athletes to limit or stop Instagram and Netflix time creeping into sleep time? How do we get athletes to prioritize sleep over “the fun stuff.”? Athletes can have knowledge and desire, but continue to miss out on what is good for them. We can know something and even believe that changing a behavior is important and yet still do nothing. Clearly, changing behavior is more complex than just common sense. If it were simple we would all make the changes we know we should make. Behavioral modification has been theoretically discussed and applied by many. More recently, Bill Beswick (British sports psychologist) presented a model that discusses 3 drivers of behavioral change, credibility, reliability, and intimacy, all underpinned by trust. In elite sport, credibility is crucial; on one hand there are the necessary qualifications to consider, and on the other hand, and perhaps even more important, is “street credibility,” which is typically related to the level of experience possessed by the sports scientist or coach. It is relatively easy to provide athletes with basic sleep information, but to be effective it can be important to consider issues such as late-night video games and caffeine use that are unique to the elite athlete. Sometimes “experts” in their fields cannot connect and engage with the athlete if they do not fully understand the athlete’s world. The second driver Beswick refers to is reliability. How many times have you heard a sport scientist promise to deliver a report or follow-up with the athlete, yet fail to deliver? If you are not reliable, athletes’ trust can be lost and athletes may not want to work with you. The third driver is intimacy, similar to emotional intelligence and reflecting how in tune you are with the athlete. How well do you listen, observe body language, and understand the athlete’s mood without even talking? Will the athlete open up to you about what may be interfering with his or her sleep or just lie and tell you everything is going fine? And, of course, many athletes may actually like sport science but not like the sport scientist they work with.
Current theories consider motor imagery, the mental representation of action, to have considerable functional overlap with the processes involved in actual movement preparation and execution. To test the neural specificity of motor imagery, we conducted a series of 3 experiments using transcranial magnetic stimulation (TMS). We compared changes in corticospinal excitability as people prepared and implemented actual or imagined movements, using a delayed response task in which a cue indicated the forthcoming response. TMS pulses, used to elicit motor-evoked responses in the first dorsal interosseous muscle of the right hand, were applied before and after an imperative signal, allowing us to probe the state of excitability during movement preparation and implementation. Similar to previous work, excitability increased in the agonist muscle during the implementation of an actual or imagined movement. Interestingly, preparing an imagined movement engaged similar inhibitory processes as that observed during actual movement, although the degree of inhibition was less selective in the imagery conditions. These changes in corticospinal excitability were specific to actual/imagined movement preparation, as no modulation was observed when preparing and generating images of cued visual objects. Taken together, inhibition is a signature of how actions are prepared, whether they are imagined or actually executed.
Eight athletes performed sprints under three different weighted sled conditions – 1x50% body mass, 2x50% body mass, 3x50% body mass followed by unweighted sprints (15m) after 4,8,12 min rest. Significantly faster sprint times for 3x50% body mass protocol following 8min rest compared to 1x50%, 2x50%
A distinguishing factor explaining the capacities of professional athletes is their ability to learn how to process complex dynamic visual scenes.
Reactive strength and sprint acceleration are important for COD speed, but those qualities are not associated with defensive agility performance.
Unlike physical training, skill acquisition does not currently utilize periodization to plan, monitor and evaluate programs.
Motor learning is related to the information arising from performance. Authors look at practice variables such as skill level and task difficulty.
Game style was measured using 12 performance indicators. This analysis can highlight areas of concern in specific play periods or phases and help with organizing training drills and practice.
Aim of this paper is to describe some of the challenges faced by high-performance coaches and athletes who may wish tot use implicit motor learning to frame potential solutions with respects to Australian NRL. Books I keep an open Word document on my computer where I write up all my random thoughts, quotes I hear, research I like, notes from books/podcasts/lectures. I look back on this document every couple of weeks to remind myself of things I found important. Decided I would take a little time to organize this file and post it in hopes other coaches may gain something from it. Here's what the Table of Contents looks like... Table of Contents Books…………………………………………………………………………………………. 3 Notes………………………………………………………………………………………... 12 Research…………………………………………………………………………………... 24 Articles…………………………………………………………………………………….. 34 Sample Programs……………………………………………………………………… 35 You can read here, or download the file. Enjoy! 
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Michael Zweifel CSCS-Owner and Head of Sports Performance. National Player of the Year in Division 3 football. Works with athletes including NFL, NHL, and Olympic athletes. Archives
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