Cultivation of College Basketball Referee Ability Using Infrared Thermal Imaging Target Recognition and Tracking System

With the development of economy and culture and the improvement of infrastructure, basketball is becoming more and more popular. At the same time, whether in school or society, basketball events are increasing, and the demand for basketball referees is also rising. As the base and cradle of training basketball referees, colleges and universities are important places for incubating basketball referees. However, the basketball referee ability cultivated in colleges and universities is still lacking, which cannot meet the increasingly standardized basketball events and basketball training. Infrared thermal imaging has the characteristics of passive imaging, high recognition accuracy, and strong anti-interference. It is especially suitable for tracking and testing basketball players, and this is expected to further improve the comprehensive ability of basketball referees. Based on this, a target recognition and tracking system based on infrared thermal imaging is proposed in this study. Its purpose is to use it to carry out comprehensive ability training for college basketball referees. Experiments show that target recognition and tracking based on infrared thermal imaging can improve the comprehensive ability of basketball referees by 40.32%, and the awareness of basketball referees to fouls has also reached 88.6%. This fully shows that the target recognition and tracking system based on infrared thermal imaging can effectively improve the comprehensive ability of basketball referees and make basketball more regular and standardized.

Intelligent Correction Method of Shooting Action Based on Computer Vision

Aiming at the problem that the students' long-term use of nonstandard shooting action leads to poor basketball teaching effect, an intelligent correction method of shooting action based on computer vision is proposed. Combined with the principle of computer vision, the image acquisition model of basketball shooting action is constructed. The edge contour and adaptive feature segmentation of basketball images are detected, and abnormal shooting movements are recognized. The intelligent correction model of shooting action is constructed, and the intelligent correction of shooting action is realized. Finally, through experiments, it is proved that the visual analysis and intelligent correction effect of basketball shooting action are obviously better, and it can correct shooting action in real time and accurately.

Reliability of live and video-based coding in netball using the NetballStats application

Understanding reliability of performance analysis tools is important to ensure match to match comparisons can be undertaken with the knowledge of consistency between coding situations. There are few published studies examining the reliability of commonly used performance analysis tools. The aim of this project was to assess the inter- and intra-rater reliability of the NetballStats application and to make comparisons between live and video-based coding situations. Two ‘coders’ coded eight netball matches using the NetballStats application, coding each match live, then twice from video. Level of agreement was assessed for frequency counts across the variables coded. Results showed that intra-rater agreement was higher than inter-rater agreement and that reliability from video coding is better than from live coding. High frequency events automatically coded by the application and events that are well defined had greater levels of agreement than lower frequency events and subjectively judged events. Live coding situations underrepresent occurrence of events, particularly for high frequency events such as ‘possession’. To ensure reliability between coders, clubs should provide an extensive training program to coders with clear instructions on coding subjective events. Coaches should be aware that live coding underestimates some event types and factor this into their decision making processes.

Multidirectional basketball activities load different regions of the tibia: A subject-specific muscle-driven finite element study

The tibia is a common site for bone stress injuries, which are believed to develop from microdamage accumulation to repetitive sub-yield strains. There is a need to understand how the tibia is loaded in vivo to understand how bone stress injuries develop and design exercises to build a more robust bone. Here, we use subject-specific, muscle-driven, finite element simulations of 11 basketball players to calculate strain and strain rate distributions at the midshaft and distal tibia during six activities: walking, sprinting, lateral cut, jumping after landing, changing direction from forward-to-backward sprinting, and changing direction while side shuffling. Maximum compressive strains were at least double maximum tensile strains during the stance phase of all activities. Sprinting and lateral cut had the highest compressive (-2,862 ± 662 με and -2,697 ± 495 με, respectively) and tensile (973 ± 208 με and 942 ± 223 με, respectively) strains. These activities also had the highest strains rates (peak compressive strain rate = 64,602 ± 19,068 με/s and 37,961 ± 14,210 με/s, respectively). Compressive strains principally occurred in the posterior tibia for all activities; however, tensile strain location varied. Activities involving a change in direction increased tensile loads in the anterior tibia. These observations may guide preventative and management strategies for tibial bone stress injuries. In terms of prevention, the strain distributions suggest individuals should perform activities involving changes in direction during growth to adapt different parts of the tibia and develop a more fatigue resistant bone. In terms of management, the greater strain and strain rates during sprinting than jumping suggests jumping activities may be commenced earlier than full pace running. The greater anterior tensile strains during changes in direction suggest introduction of these types of activities should be delayed during recovery from an anterior tibial bone stress injury, which have a high-risk of healing complications.

Accelerated Return to Play in Professional Basketball Players With Surgically-Treated Metacarpal Shaft Fractures

BACKGROUND

Traditional rehabilitation protocols for surgically treated metacarpal shaft fracture allow for return to play at 6-8 weeks post-operative. This may be devastating for the elite athlete. We outline a protocol that may allow for professional basketball players to successfully return to sport within four weeks following surgery.

METHODS

Professional basketball players who sustained non-thumb metacarpal shaft fractures were included. All athletes underwent open reduction and internal fixation of the injured metacarpal. Patients were subsequently enrolled into an accelerated rehabilitation protocol.

RESULTS

The five athletes in our case series successfully passed return to sport testing within four weeks of surgery.

CONCLUSION

A plate and screw construct can potentially allow for professional basketball players to return to play in half the time. Future research studies should include a larger pool of athletes to further investigate accelerated rehabilitation following surgical fixation of metacarpal fractures. Level of Evidence: IV.

Deep Learning Algorithm-Based Target Detection and Fine Localization of Technical Features in Basketball

Based on SSD to detect players, a super-pixel-based FCN-CNN player segmentation algorithm is proposed to filter out the complex background around players, which is more conducive to the subsequent pose estimation for target detection and fine localization of basketball technical features. The high resolution capability of CNN is used to extract images and perform computational preprocessing to identify typical basketball sports actions in video streams-rebounds, shots, and passes-with an accuracy rate of up to 95.6%. By comparing with three classical classification algorithms, the results prove that the target detection system proposed in this study is effective for target detection and fine localization of basketball sports technical features.

Physical Persistency across Game Quarters and during Consecutive Games in Elite Junior Basketball Players

Given the intermittent nature of basketball and the different demands that occur during playing time that are specific to every level of competition, the ratio of accelerations/decelerations and the intensity level across quarters were evaluated in female elite junior basketball players (n = 48; age: 16.8 ± 0.7 years; height: 1.76 ± 0.07 cm; body mass: 67.2 ± 6.2 kg). The following variables were analyzed to determine physical persistency across game quarters:(a) total distance covered (m), (b) high-intensity running (HIR) (14–21 km·h⁻¹) distance covered (m), (c) sprint (21–30 km·h⁻¹) distance covered (m), (d) total accelerations (n), (e) total decelerations (n), (f) relative accelerations (n·min⁻¹), (g) relative decelerations (n·min⁻¹), (h) ratio of acceleration/deceleration (A/D), (i) total jumps (j) relative jumps (n·min⁻¹) (k) player load (AU). using the WIMU PRO^® system. Higher but shorter acceleration intensity occurred during the last quarters due to the tight results of the matches. The results suggest that high-intensity efforts such as sprints and HIR seem to increase the A/D ratio (guard and forward positions). Therefore, specific conditioning, as well as eccentric strength training, could be included by practitioners in training programs to improve the performance of these positions during competition, especially as a prior preparation to a game-congested event. Centers seem to have a more variable performance through quarters than do other positions, perhaps highlighting the need for specific conditioning strategies.

Acute Effects of Caffeine on Overall Performance in Basketball Players—A Systematic Review

Caffeine supplementation has become increasingly popular among athletes. The benefits of caffeine include delaying the negative effects of fatigue, maintaining a high level of physical and mental performance, and improving certain abilities necessary for sport success. Given the complex nature of basketball, caffeine could be a legal, ergogenic stimulant substance, which will positively affect overall basketball performance. The purpose of this systematic review was to summarize evidence for the effect of acute caffeine ingestion on variables related to the basketball performance. Web of Science, PubMed, Scopus and ProQuest, MEDLINE, and ERIC databases were searched up to February 2021. Studies that measured the acute effect of caffeine on basketball performance were included and analyzed. Eight studies published between 2000 and 2021 were included in the analysis. Pre-exercise caffeine intake increased vertical jump height, running time at 10 and 20 m without the ball, overall basketball performance (number of body impacts, number of free throws, rebounds, and assists) during simulated games, and reduced the time required to perform a basketball-specific agility test. Equivocal results between caffeine and placebo groups were found for aerobic capacity, free throw and three-point accuracy, and dribbling speed. Pre-exercise caffeine ingestion did not affect RPE, but insomnia and urinary excretion were increased. The pre-exercise ingestion of 3 and 6 mg/kg caffeine was found to be effective in increasing several physical performance variables in basketball players during sport-specific testing and simulated matches. However, considering the intermittent nature and complexity of basketball, and individual differences between players, future studies are needed.

Phase-Specific Predictors of Countermovement Jump Performance That Distinguish Good From Poor Jumpers

ABSTRACT

Krzyszkowski, J, Chowning, LD, and Harry, JR. Phase-specific predictors of countermovement jump performance that distinguish good from poor jumpers. J Strength Cond Res 36(5): 1257-1263, 2022-The modified-reactive strength index (RSImod) is commonly examined during the countermovement vertical jump (CMJ) to assess neuromuscular characteristics (i.e., explosiveness, fatigue, adaptation, etc.) of an athlete. However, both phase-specific variables explaining RSImod and corresponding differences between good and poor jumpers are not well understood in trained populations. This study sought to (a) identify predictors of RSImod during the CMJ based on phase-specific temporal and rate of force development (RFD) variables, and (b) identify differences in those predictors between performers with high and low RSImod performances from a sample of collegiate male basketball players (n = 22; 20 ± 2 years; 1.99 ± 0.06 month; 93.8 ± 7.5 kg). Subjects performed 3 maximal effort CMJ trials while ground reaction force data was recorded using 2 force platforms. Phase-specific temporal and RFD variables were calculated and entered into separate stepwise regression models using backward elimination to identify predictors RSImod. Individuals were then categorized into high (n = 11; RSImod = 0.68 ± 0.10) and low (n = 11; RSImod = 0.48 ± 0.04) RSImod groups according to the overall median RSImod (RSImod = 0.55). Independent t-tests (α = 0.05) were conducted and supplemented by Cohen's d effect sizes (d ≥ 1.2, large) to compare groups relative to significant predictors identified by the linear regression models and related variables. The temporal regression model (R2 = 0.530) retained unloading time and concentric time, whereas the RFD regression model (R2 = 0.429) retained unloading RFD and braking RFD. The high RSImod group exhibited significantly greater RSImod scores (d = 2.51, p < 0.001) and jump heights (d = 1.58, p < 0.001), shorter times to takeoff (d = 1.27, p = 0.007) and concentric times (d = 1.51, p = 0.002), and a greater braking RFD (d = 1.41, p = 0.005) than the low RSImod group. Individuals targeting enhanced CMJ performance may consider exploring strategies or interventions to develop quicker unloading and concentric phases and increasing eccentric RFD abilities.

Understanding load in netball – An analysis of multiple seasons, phases, and teams

Studies of training and competition load in sport are usually based on data that represents a sample of a league and or annual training program. These studies sometimes explore important factors that are affected by load, such as training adaptations and injury risk. The generalisability of the conclusions of these studies, can depend on how much load varies between seasons, training phases and teams. The interpretation of previous load studies and the design of future load studies should be influenced by an understanding of how load can vary across seasons, training phases and between teams. The current study compared training loads (session rating of perceived exertion x session duration) between all (8) teams in an elite Netball competition for multiple (2) season phases and (2) seasons. A total of 29,545 records of athlete session training loads were included in the analysis. Linear mixed models identified differences between seasons and training phases (p < .05). There were also differences between teams and a complex set of interactions between these three factors (season, phase, and team) (p < .05). While the absolute value of the training loads reported here are only relevant to elite netball, these results illustrate that when data is sampled from a broader context, the range and variation in load may increase. This highlights the importance of cautiously interpreting and generalisation of findings from load studies that use limited data sets.

Effects of Cooperation and Competition on Performance, Emotion, and Effort: Goal and Means Interdependence

Social interdependence theory proposes that task structure influences performance via social interaction. Using this framework, we examined sport performance. Fifty-six males performed a basketball task under four conditions: as an individual (individual, perform your best) and as a member of a team of two (cooperation, where teammates sought to better their individual performance; means independent competition, where two teams competed sequentially to outperform the other team; means interdependent competition, where two teams competed simultaneously to outperform the other team). Task performance (points) was better during means independent competition than other conditions. Anxiety and effort peaked during the competitions and enjoyment was greater during competition and cooperation than during the individual condition. Emotions, effort, and actions are discussed as explanations for the performance effects. Social interdependence theory provides a valuable framework to understand emotion, motivation, and performance. Team competition can be used to promote effort and enhance performance in sport.

The Defender's Vision-Gaze Behavior of One-on-One Defenders in Basketball

In fast-paced team sports, anticipation is one important element in defense strategies. The primary objective of this study was to examine the recommendation for action and use of defensive gaze strategies by defensive players in basketball. Four national-level expert-basketball coaches were interviewed and a field study with mobile eye-tracking devices was conducted on 16 expert and 16 novice players defending in a one-on-one situation. Differences in relative fixation times between experts and novices were elaborated for the predetermined gaze zones-head, ball, torso, and feet-as given by the expert coaches. This was done for three phases of the movement sequence: receiving, dribbling, and shooting. The results of the interviews with expert coaches indicated that the existing coaching doctrine instructs players to look at the torso of an opponent to avoid being vulnerable to fakes. Surprisingly, our findings with the players showed a discrepancy in the evaluated gaze behavior of the experts and novices. For the receiving and dribbling phase, experts mainly fixated their gaze on the head while novices focused on the ball. For the final shooting phase, both the groups mainly fixated their gaze on the ball. Fixating the gaze on the ball or head makes the player potentially vulnerable to deceptive movements, as video-based research has shown. Expert coaches also indicated that peripheral vision is of importance to defenders, contradicting the existing assumption in the literature that focusing on the task-relevant areas is key for anticipation performance.

Detection of Neuromuscular Deficits in Movement Pattern among Uninjured Federated Youth Basketball Players: A Cross-Sectional Study

(1) Background: The aim of the present study was to evaluate and to detect neuromuscular deficiencies in static and dynamic tests among federated youth basketball players. (2) Methods: Cross-sectional study with 778 basketball players. Specific tests and trials were conducted to evaluate members of teams from several clubs in male and female from under 12 (U12) to under 17 (U17) categories. The evaluations consisted of static physical measurements and dynamic measurements. (3) Results: 575 players were included in this study. A total of 95% of participants are unable to keep their ankle stable in monopodial loading; 86% present dynamic lower extremity valgus with statistically significant differences between categories (p = 0.004); 94% are unable to keep the pelvis stable when performing a single-leg squat; 93% are unable to keep their trunk stable when performing the same movement. During landing, 96% present dynamic lower extremity valgus. The thighs of 92% do not reach parallel (peak of jump). (4) Conclusions: The most frequent neuromuscular deficits in federated youth basketball players are related to instability, the most frequent being ankle instability, followed by lumbo-pelvic instability, dynamic postural instability and dynamic knee valgus. Deficits in jumping/landing technique are also very frequent in all the items analyzed (jumping, landing and plyometrics). The performed tests, which mostly showed a poor performance by the sample, can be indicative of injury probability.

Positional Differences in Physique, Physical Strength, and Lower Extremity Stability in Korean Male Elite High School Basketball Athletes

No studies have measured the physical strength and lower extremity stability of elite male high school basketball players. This study aimed to measure the physique, physical strength, and lower extremity stability of such athletes in Korea and analyze the differences according to their play positions. Overall, 204 male elite basketball players participated and were classified as guard (n = 97), forward (n = 69), and center (n = 38) according to their main playing position. All sub-variables of physique were significantly higher in the forward and center groups than in the guard group, and were significantly higher in the center group than in the forward group. Strength was significantly higher in the forward and center groups than in the guard group. Agility and speed were significantly faster in the guard group than in the forward and center groups. Y-balance analysis showed that the composite score of both feet tended to be higher in the order of center, forward, and guard, and it was significantly higher in the guard group than in the center group. These results could be used as basic data for selecting players, determining positions, and setting specific training goals for players of each position to improve physical strength and prevent injuries.

The effects of easy goals versus difficult goals on acquisition and retention of a sport skill in children with intellectual disability

The purpose of the present study was to examine the effects of easy goals versus difficult goals on acquisition and retention of basketball free throws in children with intellectual disability. Twenty-one children with intellectual disability were randomly assigned to an easy goals or difficult goals group. The participants were required to improve their basketball free throws according to their own scores in the previous exercise session. More difficult goals were set for the difficult goals group than for the easy goals group. The groups exercised the task for nine sessions. Both groups performed pretest, acquisition, and retention tests. Results showed that participants with easy goals improved their performance while the participants with difficult goals failed to improve their performance. These findings indicate that providing children with intellectual disability with easy goals facilitates the process of sport skill learning.

Netball Shoots for Physical and Mental Wellbeing in Samoa: A Natural Experiment

Sport-for-development programs claim to address key determinants of recreational physical activity participation and subsequent development outcomes in low-income settings. We conducted a natural experiment with pre–post measures taken from women in the 12 villages in Samoa, some of which voluntarily participated in the sport-for-development intervention. The intervention comprised a six-week netball league delivered by local volunteers who attended coaching workshops, received ongoing support from the national governing body and were provided with infrastructure and equipment to conduct local training sessions. Changes in netball participation, recreational physical activity, body composition, mental wellbeing and socio-ecological determinants of physical activity were compared between intervention and comparison villages using a univariate ANOVA. The intervention reached women who participated in little recreational physical activity and had poor physical and mental wellbeing. Program uptake was higher in villages with the strongest social support for netball participation. Local social support and capacity to independently organize netball activities increased. There were concurrent improvements in netball participation, physical activity levels, mental wellbeing and body weight in the intervention villages. Our findings support scaling-up of the intervention in similar settings but preceding this with formative evaluation to identify low active communities that are “primed” to participate in the proposed activity.

Osteoid Osteoma in an Adult Wheelchair Basketball Player Mimicking Musculoskeletal Shoulder Pain: Red Flag or a Red Herring?

Osteoid osteoma (OO) is a relatively common, benign bone-forming tumour, which mainly occurs on the long tubular bones of the limbs in adolescents. Usually, the OO is classified based on its localisation. Night-time pain is the major symptom of OO, which is commonly relieved using non-steroidal anti-inflammatory drugs, while surgery is required only for those patients with severe pain or in case of failure of previous conservative treatments. Our case report describes a 56-year-old male basketball player who self-referred to our outpatient physical therapy with a shoulder pain complaint. Considering the anamnesis and the physical examination, the physical therapist referred the patient to an orthopaedic surgeon, who suggested a detailed imaging investigation. The peculiarity of this clinical case is the overlapping of two clinical presentations: the symptomatology of the OO and the concurrent mechanical disorder due to a rotator cuff tendinopathy.

Ergo-Nutritional Intervention in Basketball: A Systematic Review

Using nutritional supplements is a widespread strategy among basketball players to ensure the appropriate provision of energy and nutrients to avoid certain complaints. Particularly in basketball, there is no consensus on the type, quantity or form of use in which these supplements should be administered. Therefore, the main aim of this systematic review is to highlight the ergo-nutritional aids that may be effective in basketball. A structured search was carried out following the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA®) guidelines in the Medline/PubMed and Web of Science, Cochrane Library, and Scopus databases until 31 December 2021; no year restriction was applied to the search strategy. There were no filters applied to the basketball players' level, gender, race, or age to increase the power of the analysis. The results of this systematic review have shown that the effective dose of caffeine to enhance anaerobic performance and the feeling of vigorousness and energy ranges from 3 to 6 mg·kg-1, showing more positive effects when is supplemented 60-75 min before exercise in the morning and in test-based task. On the other hand, vitamin E (ranging from 200 to 268 mg), vitamin D (10,000 IU) and EPA (2 g) may have a potential role in recovery and wellness. The primary limitation of this study is the scarcity of studies related to nutritional supplementation in basketball players. However, a major strength is that this is the first systematic review describing what ergo-nutritional aids may be specifically helpful for basketball. Despite the need for future studies, certain nutritional supplements may have promising advantages for basketball (long-term supplementation of nitrates for recovery), whereas others (β-alanine, sodium bicarbonate, and acute nitrate supplementation) might theoretically be regarded as not interesting for basketball, or even not recommended by the World Anti-Doping Agency (WADA) as bovine colostrum.

The Home Advantage in the National Basketball Association Conference Finals and Finals Series From 1979 to 2019: A Mediation Analysis of Offensive and Defensive Skills

This study examined the home advantage effect in decisive National Basketball Association Conference Finals and Finals series playoff games from 1979 to 2019 (the 3-point shot era). We also examined the potential contribution of various offensive- and defensive-based skills and whether these skills mediated the relationship between game status (decisive vs. nondecisive) and outcome (win vs. loss). Overall, we found evidence of a home court advantage with the home team winning 63% of the decisive playoff games and 66% of the nondecisive playoff games. After adjusting for multiple comparisons and regular season win percentage, the home team had significantly more defensive rebounds and steals in Game 5 when trailing 3-1 going into that game. Mediation analyses did not reveal any significant findings when examining the impact of decisive game status on performance through offensive and defensive skills, thus suggesting there are other explanations for the home advantage effect.

The hot hand in the wild

Streaks of success have always fascinated people and a lot of research has been conducted to identify whether the “hot hand” effect is real. While sports have provided an appropriate platform for studying this phenomenon, the majority of existing literature examines scenarios in a vacuum with results that might or might not be applicable in the wild. In this study, we build on the existing literature and develop an appropriate framework to quantify the extent to which success can come in streaks—beyond the stroke of chance—in a natural environment. Considering in-game basketball game situations, our analysis provides statistical evidence that individual players do indeed exhibit the hot hand in varying degrees, that is, individual players can consistently get in a streak of successful shots beyond random chance. However, as a whole, the average player exhibits shooting regression, that is, after consecutive makes he tends to perform below expectations. Even though our results are based on a sports setting, we believe that our study provides a path towards thinking of the hot hand beyond a laboratory-like, controlled environment. This is crucial if we want to use similar results to enhance our decision making and better understand short and long term outcomes of repeated decisions.

Can Stephen Curry really know?—Conscious access to outcome prediction of motor actions

The NBA player Stephen Curry has a habit of turning away from the basket right after taking three-point shots even before the ball reaches the basket, suggesting that he can reliably predict whether the just released shot will hit or not. In order to use this “knowledge” to deliberately decide which action to take next, Stephen Curry needs conscious access to the results of internal processes of outcome prediction and valuation. In general, computational simulations and empirical data suggest that the quality of such internal predictions is related to motor skill level. Whether the results of internal predictions can reliably be consciously accessed, however, is less clear. In the current study, 30 participants each practiced a virtual goal-oriented throwing task for 1000 trials. Every second trial, they were required to verbally predict the success of the current throw. Results showed that on average, verbal prediction accuracy was above an individually computed chance level, taking into account individual success rates and response strategies. Furthermore, prediction accuracy was related to task skill level. Participants with better performances predicted the success of their throws more accurately than participants with poorer performances. For the poorer performing individuals, movement execution was negatively affected when the verbalized predictions were required. They also showed no noticeable modulation of speech characteristics (response latency) for correct and incorrect predictions as observed in the high performers.

Effects of Direction-Specific Training Interventions on Physical Performance and Inter-Limb Asymmetries

This study analyzed the effects of two different training programs on functional performance and inter-limb asymmetries in basketball players. Twenty-four elite youth basketball players were randomly assigned to a training program including variable unilateral horizontal movements (VUH, n = 12) or unilateral lateral movements (VUL, n = 12). Eccentric-overload training (EOT) was performed twice a week for a six-week period. Functional performance assessment included a countermovement jump test, unilateral multidirectional jumping tests (i.e., lateral, horizontal, and vertical), a rebound jump test, a limb symmetry index, a 25 m linear sprint test, and several change of direction (COD) tests. Within-group analysis showed substantial improvements in almost all functional tests in both groups (ES = 0.35–0.89). Furthermore, almost all jumping asymmetries were improved in both groups (ES = 0.38–0.69) except for vertical jumping asymmetry in VUL (ES = −0.04). Between-group analyses showed a substantial and possibly better performance in vertical jumping asymmetry and 5 m in VUH compared to that of VUL, respectively. In contrast, lateral jumping with left (ES = 1.22) and right leg (ES = 0.49) were substantially greater in VUL than in VUH. Specific force-vector training programs induced substantial improvements in both functional performance tests and inter-limb asymmetries, although greater improvements of lateral and horizontal variables may depend on the specific force vector targeted.

Specific Physical Ability Prediction in Youth Basketball Players According to Playing Position

This study investigated the hierarchical structure of physical characteristics in elite young (i.e., U17-U19) basketball players according to playing positions. In addition, their predictive value of physical characteristics was determined for the evaluation of players’ physical preparedness. Sixty elite male basketball players performed 13 standardized specific field tests in order to assess the explosive power of lower limbs, speed, and change-of-direction speed. They were divided into three groups according to playing positions (guard [n = 28], forward [n = 22], center [n = 10]). The basic characteristics of the tested sample were: age = 17.36 ± 1.04 years, body height = 192.80 ± 4.49 cm, body mass = 79.83 ± 6.94 kg, and basketball experience = 9.38 ± 2.10 years for guards; age = 18.00 ± 1.00 years, body height = 201.48 ± 3.14 cm, body mass = 90.93 ± 9.85 kg, and basketball experience = 9.93 ± 2.28 years for forwards; and age = 17.60 ± 1.43 years; body height = 207.20 ± 3.29 cm, body mass = 104.00 ± 9.64 kg, and basketball experience = 9.20 ± 1.62 years for centers. For all playing positions factor analysis extracted three factors, which cumulatively explained 76.87, 88.12 and 87.63% of variance, respectively. The assessed performance measures were defined as significant (p < 0.001), with regression models of physical performance index (PP_INDEX). PP_INDEX of guards = −6.860 + (0.932 × t-test) − (1.656 × Acceleration 15 m) − (0.020 × Countermovement jump); PP_INDEX of forwards = −3.436 − (0.046 × Countermovement jump with arm swing) − (1.295 × Acceleration 15 m) + (0.582 × Control of dribbling); PP_INDEX of centers = −4.126 + (0.604 × Control of dribbling) − (1.315 × Acceleration 15 m) − (0.037 × Sargent jump). A model for the evaluation of physical performance of young basketball players has been defined. In addition, this model could be used as a reference model for selection procedures, as well as to monitor the efficacy of applied training programmes within the short, medium and long-term periodization.

Evaluation Algorithm for Team Strength Based on the Collected Healthcare Data through IoT and Smart Devices

In the past, the fans used to evaluate the strength of the team according to the victory and defeat ranking or according to their own intuition and preferences, however, the strength of the team is difficult to measure in analytical figures. The team's winning rate is not the only factor to be considered to determine the strength of the team. There are many factors to be considered for determining the strength of the team. According to the variation coefficient of basketball scoring frequency, the paper designs the principal model of basketball players' pitching target system. The data is captured by IoT devices and smart devices. The algorithm sets the number of the frequency of Gabor filter transformation features, controls the error accumulation, extracts the cascade features of basketball score video, constructs the video conversion discrimination rules, detects the basketball target, and obtains the tracking target contour to frame information. Finally, it realizes the target tracking detection of the team based on the team strength using an evaluation algorithm. The aim of this research work is to determine the strength of the team based on the healthcare data, team cohesiveness, and variance coefficient of basketball score frequency. The study on the coefficient of variation for basketball score frequency in teams can provide a theoretical research direction for team strength evaluation and meet the real-time needs of the coefficient of variation of basketball score frequency in teams. The empirical results show that the designed algorithm has the optimal execution time, more successful evaluation targets, high efficiency, and more reliability in evaluating the strength of the team.

"It Will Ruin His Career": Does Violence Against Women Really Damage the Careers of NBA Players?

Arrests for acts of violence against women are a common occurrence for professional athletes, including National Basketball Association (NBA) players. Many sports fans, players, and those involved in professional sport believe that arrests for acts of violence against women, whether they result in a conviction or not, are highly detrimental to an athlete's career. We matched all 30 NBA players arrested for acts of violence against women between 2000 and 2016 with similar players who were not arrested and examined the effects of the arrest on postarrest average annual salary and career longevity. We found no significant difference between arrested players' careers and the careers of nonarrested counterparts. From a social learning perspective, this lack of punishment or loss of reward could be an important factor in continued acts of violence against women among NBA athletes.

Individualization of Intensity Thresholds on External Workload Demands in Women's Basketball by K-Means Clustering: Differences Based on the Competitive Level

In previous studies found in the literature speed (SP), acceleration (ACC), deceleration (DEC), and impact (IMP) zones have been created according to arbitrary thresholds without considering the specific workload profile of the players (e.g., sex, competitive level, sport discipline). The use of statistical methods based on raw data could be considered as an alternative to be able to individualize these thresholds. The study purposes were to: (a) individualize SP, ACC, DEC, and IMP zones in two female professional basketball teams; (b) characterize the external workload profile of 5 vs. 5 during training sessions; and (c) compare the external workload according to the competitive level (first vs. second division). Two basketball teams were recorded during a 15-day preseason microcycle using inertial devices with ultra-wideband indoor tracking technology and microsensors. The zones of external workload variables (speed, acceleration, deceleration, impacts) were categorized through k-means clusters. Competitive level differences were analyzed with Mann–Whitney’s U test and with Cohen’s d effect size. Five zones were categorized in speed (<2.31, 2.31–5.33, 5.34–9.32, 9.33–13.12, 13.13–17.08 km/h), acceleration (<0.50, 0.50–1.60, 1.61–2.87, 2.88–4.25, 4.26–6.71 m/s²), deceleration (<0.37, 0.37–1.13, 1.14–2.07, 2.08–3.23, 3.24–4.77 m/s²), and impacts (<1, 1–2.99, 3–4.99, 5–6.99, 7–10 g). The women’s basketball players covered 60–51 m/min, performed 27–25 ACC-DEC/min, and experienced 134–120 IMP/min. Differences were found between the first and second division teams, with higher values in SP, ACC, DEC, and IMP in the first division team (p < 0.03; d = 0.21–0.56). In conclusion, k-means clustering can be considered as an optimal tool to categorize intensity zones in team sports. The individualization of external workload demands according to the competitive level is fundamental for designing training plans that optimize sports performance and reduce injury risk in sport.

Impact of dribbling on spatiotemporal and kinetic parameters in wheelchair basketball athletes

BACKGROUND

Wheelchair basketball is one of the most popular Paralympic sports. Dribbling a ball while propelling is a key feature of wheelchair basketball. Very few studies have investigated the biomechanical impact of dribbling. This study aims to analyze the impact of dribbling on the amplitude and symmetry of spatiotemporal and kinetic parameters of wheelchair propulsion.

METHODS

Ten experienced wheelchair basketball athletes (31.5 ± 10.6 years old; 7 men, 3 women) with various classifications performed eight 9-m sprints along a straight line on a basketball court: four sprints using classic synchronous propulsion, and four sprints while dribbling a ball down the court.

FINDINGS

Dribbling decreased velocity, mean propulsive moments and the force rate of rise, as well as increased push time, force rate of rise asymmetry and angular impulse asymmetry. All kinetic variables were asymmetric and higher on the dominant limb.

INTERPRETATION

The combination of reduced velocity and propulsive moments when dribbling indicates that wheelchair basketball athletes may deliberately preserve a safety margin of acceleration to adapt to uncontrolled ball rebounds. Dribbling was not associated with any factors associated with an increased risk of musculoskeletal disorders.

Age of Early Specialization, Competitive Volume, Injury, and Sleep Habits in Youth Sport: A Preliminary Study of US Youth Basketball

BACKGROUND

Concerns for youth sports in the United States often focus on early sport specialization, overemphasis on competition, injuries, and burnout. Little research has addressed relationships among the preceding and other concerns, including time away from organized sport, sleep, and perceptions of physical and psychological well-being.

HYPOTHESIS

There is an association between reported competitive gameplay volume and specialization, injury, and fatigue among elite youth basketball players.

STUDY DESIGN

Cross-sectional study; convenience sample.

LEVEL OF EVIDENCE

Level 4.

METHODS

An anonymous questionnaire was administered to a convenience sample of youth basketball players between 13 and 18 years of age from across the United States. Participants were queried about multiple factors, including the extent of their participation in organized basketball and other sports, time away from organized basketball, injury, sleep, and feelings of exhaustion related to basketball participation.

RESULTS

A total of 772 participants (145 girls, 627 boys) completed a survey. All participants played for a select or elite club basketball team and/or a high school basketball team. Overall, 49% played more than 50 games within the past year. A total of 73% were specialized in basketball, 58% prior to age 14 years, and 35% prior to age 11 years. In all, 70% reported less than 1 month away from organized basketball within the past year, and 28% reported no time away. A total of 54% reported sleeping less than the recommended 8 hours each night during the school year. Within the prior year, 55% reported feeling physically exhausted and 45% reported feeling mentally exhausted from basketball. Regression analysis did not find any significant relationships between early specialization prior to age 14 years and basketball-related injury or feelings of mental or physical exhaustion.

CONCLUSION

In this select group of youth basketball players, the majority specialized in basketball prior to age 14 years and reported a large number of competitive events with little time away from organized basketball.

CLINICAL RELEVANCE

The results from a sample of highly competitive youth basketball players indicate issues that warrant further attention and research regarding the potential impact of specialization, frequent competitions, lack of time away from organized sport, and perceptions of well-being in young athletes.

Small Relative Age Effect Appears in Professional Female Italian Team Sports

The relative age effect (RAE) concerns those (dis)advantages and outcomes resulting from an interaction between the dates of selection and birthdates. Although this phenomenon is well known in a male context, limited data are available in female sports. Thus, the aim of this study was to quantify the prevalence and magnitude of the RAE in a female Italian context at the professional level in basketball, soccer, and volleyball. A total of 1535 birthdates of elite senior players were analyzed overall and separately between early and late career stages. Chi-square goodness-of-fit tests were applied to investigate the RAE in each sport. An asymmetry in birthdates was observed in all sports (Crammer's V ranged = 0.10-0.12). Players born close to the beginning of the year were 1.62 and 1.61 times more likely to reach first and second Italian divisions of soccer and volleyball, respectively, than those born in the last part of the year. A small over-representation of female athletes born close to the beginning of the year is evident at the senior professional level in all Italian investigated team sports. In soccer, this trend was more evident in the first stage of a senior career.

"The Competitive Season and Off-Season": Preliminary Research concerning the Sport-Specific Performance, Stress, and Sleep in Elite Male Adolescent Basketball Athletes

BACKGROUND

Through scholastic sports programs, adolescent athletes compete to represent their communities. However, few studies investigate the changes in physiological and mental profiles during varied sport periodization among this population. Therefore, the purpose of this study was to compare the changes in sports performance and stress-related biomarkers between the competitive season (CS) and off-season (OS) in elite adolescent basketball players.

METHOD

Nine elite Division I male basketball players (age: 15-18 years. old) participated in this study. Basketball-specific performance, salivary dehydroepiandrosterone sulfate (DHEA-S)/cortisol levels, mood state, and sleep quality were all accessed during the CS and OS periods.

RESULTS

The training load during OS was 26.0% lower than CS (p = 0.001). Muscle mass, aerobic capacity, 10 m sprint, and Abalakov jump (AJ) power during OS were greater than that during CS (+2.2-9.8%, p < 0.05), but planned agility was greater during CS (p = 0.003). The salivary DHEA-S/cortisol was greater during CS than during OS (p = 0.039). The overall mood state and sleep quality did not differ between periods, but the POMS-tension was higher during CS (p = 0.005).

CONCLUSION

The present study demonstrates that muscle mass, aerobic capacity, peak AJ power, and 10 m sprint performance, but not planned agility, were greater during OS compared to CS among elite adolescent basketball players. Furthermore, the stress-related responses reflected by the D/C ratio and mood tension were relatively lower during the OS in these athletes. Thus, this study suggests that coaches and sport science professionals should closely monitor athletes' training states across varied training/competition periods to better react to modifying training or recovery plans.

Mental fatigue increases across a 16-week pre-season in elite female athletes

OBJECTIVES

To examine potential changes in mental and physical fatigue across an elite netball pre-season training phase and relationships between mental fatigue, physical fatigue, salivary cortisol (sCort) and alpha-amylase (sAA).

DESIGN

Observational with repeated measures.

METHODS

Across a 16-week pre-season, 10 elite female netballers (25.3 ± 3.7y) rated their physical fatigue, mental fatigue and readiness to perform on 100-mm visual analogue scales, and provided salivary samples for sCort and sAA analyses.

RESULTS

Linear mixed model analyses revealed elevated (p < 0.05) ratings of mental fatigue for weeks 12, 14 and 15 v 1; 12, 14 and 15 v 4 and 14 v 7. Higher (p < 0.05) ratings of physical fatigue were reported on weeks 6, 10, 11 and 12-16 compared to week 4; and 10 and 13 compared to week 7. Moderate and large ES differences were found between multiple weeks. Mental and physical fatigue demonstrated a shared variance of 14.3% (r = 0.38, p < 0.001) and an inverse relationship was observed between mental fatigue and readiness to perform (r = -0.50; p < 0.001). Changes in sCort nor sAA were not related to changes in mental or physical fatigue.

CONCLUSIONS

Mental fatigue fluctuated across the 16-week pre-season phase with elevated ratings observed in the later weeks. Whilst value remains in identifying subjective tools to assess mental fatigue; salivary biomarkers do not appear to be a suitable objective indicator of mental fatigue in the applied sporting environment. Practitioners should work to identify and manage mental fatigue with the same level of importance given to the periodisation of physical fatigue.

Internal and External Load Control in Team Sports through a Multivariable Model

Data related to 141 sessions of 10 semi-professional basketball players were analyzed during the competitive period of the 2018-2019 season using a multivariable model to determine possible associations between internal and external load variables and fatigue. Age, height, weight, sessional rate of perceived exertion (sRPE), summated-heart-rate-zones, heart rate variability, total accelerations and decelerations were the covariates, and post-session countermovement jump loss (10% or higher) the response variable. Based on the results observed, a rise in sRPE and accelerations and decelerations could be associated with increased lower-body neuromuscular fatigue. Observing neuromuscular fatigue was 1,008 times higher with each additional sRPE arbitrary unit (AU). Each additional high-intensity effort also increased the probability of significant levels of neuromuscular fatigue by 1,005 times. Fatigue arising from demanding sporting activities is acknowledged as a relevant inciting event leading to injuries. Thus, the methodology used in this study can be used then to monitor neuromuscular fatigue onset, also enhancing proper individual adaptations to training.

Effects of large gatherings on the COVID-19 epidemic: Evidence from professional and college sports

We compare COVID-19 case loads and mortality across counties that hosted more versus fewer NHL hockey games, NBA basketball games, and NCAA basketball games during the early months of 2020, before any large outbreaks were identified. We find that hosting one additional NHL/NBA game in March 2020 leads to an additional 7520 cases and 658 deaths. Similarly, we find that hosting an additional NCAA Division 1 men's basketball game in March 2020 results in an additional 34 deaths. Back-of-the-envelope calculations suggest that the per-game fatality costs were 200-300 times greater than per-game spending.

Impact of Match Type on Exercise Volume and Intensity of Semi-Professional Basketball Referees During a Competitive Season

Identification of the exercise volume and intensity of basketball referees, across competitive match types based on competition sex and level, would assist in developing appropriate training regimes. Purpose: The aims of this study were to quantify and compare the exercise volume and intensity encountered by semiprofessional basketball referees during different match types across a competitive season. Method: Sixteen referees participated and were monitored for absolute and relative PlayerLoad (PL) using microsensors during 25 semiprofessional matches (12 men's, 13 women's, 17 regular season, eight playoff). Comparisons between match types (men's vs. women's; regular season vs. playoff) were examined via independent t-tests or Mann-Whitney U tests, and repeated measures ANOVA with the magnitude of differences calculated via effect size. Results: Referees experienced an absolute PL of ~365 arbitrary units (AU) per match that was similar for men's, women's, regular season, and playoff matches during a competitive season. Relative PL was significantly greater (5.35 ± 0.82 vs. 4.26 ± 0.59 AU.min^-1, p < .001, effect size = 1.57) during women's matches with a greater proportion of each quarter and match spent within PL band 2 compared to men's matches (11.6 ± 2.2 vs. 8.8 ± 1.4%, p < .001, effect size = 1.53), likely due to a reduced number of referees officiating. Minimal differences existed between the regular season and playoff matches for absolute PL, relative PL, and proportion of quarter/match time within PL bands. Conclusion: The current study confirmed that referees experienced considerable exercise volume and intensity per match during a competitive season with these influenced primarily by referee configuration. The current results provide crucial information to develop effective training regimes for referees during a competitive season.

Effects of large gatherings on the COVID-19 epidemic: Evidence from professional and college sports

We compare COVID-19 case loads and mortality across counties that hosted more versus fewer NHL hockey games, NBA basketball games, and NCAA basketball games during the early months of 2020, before any large outbreaks were identified. We find that hosting one additional NHL/NBA game in March 2020 leads to an additional 7520 cases and 658 deaths. Similarly, we find that hosting an additional NCAA Division 1 men's basketball game in March 2020 results in an additional 34 deaths. Back-of-the-envelope calculations suggest that the per-game fatality costs were 200-300 times greater than per-game spending.

Adaptation of Anaerobic Field-Based Tests for Wheelchair Basketball Athletes

Purpose: The aim of this study was to propose field-based tests to estimate the anaerobic power of wheelchair basketball athletes. Methods: Eleven lower class wheelchair basketball players performed the Wingate test (WT) and two field-based tests (repeated sprints) of 15 (S-15) and 20 (S-20) meters. The WT provides data in Watts (W). The S-15 and S-20 are recorded in seconds and converted to W using the Running-based Anaerobic Sprint Test (RAST) equation. The participants also completed other field-based tests, such as right and left handgrip strength (HGS) tests and the medicine ball chest pass test. In addition, body mass and height were measured, and the body composition was estimated. The field-based tests and anthropometric measures were used to estimate WT peak power (PP) and mean power (MP) using multiple linear regressions. Results: The field-based tests underestimated the anaerobic power measured with the WT (in W). However, a linear regression model based on S-15 PP, right HGS, height, and body mass explained 76% (P= .040) of the WT PP variance. Another model based on S-15 MP and right HGS explained 72% (P= .006) of the WT MP variance. Both models had excellent reliability (ICC > 0.90). Conclusion: WT PP can be estimated using S-15 PP (W), right HGS, height, and body mass. The WT MP is predicted using S-15 MP (W) and right HGS. Therefore, a combination of field-based tests and anthropometric measures seem to be appropriate to determine anaerobic power of lower class wheelchair basketball athletes.

The Application of Accelerometer-Derived Moving Averages to Quantify Peak Demands in Basketball: A Comparison of Sample Duration, Playing Role, and Session Type

ABSTRACT

Fox, JL, Conte, D, Stanton, R, McLean, B, and Scanlan, AT. The application of accelerometer-derived moving averages to quantify peak demands in basketball: A comparison of sample duration, playing role, and session type. J Strength Cond Res 35(12S): S58-S63, 2021-The purpose of this was to study compare peak external workload intensities in basketball using accelerometer-derived moving averages between different sample durations (0.5-5 minutes), session types (training vs. game-play), and playing roles (starting vs. bench players). Five starting and 3 bench players were monitored over a 15-week competitive season using accelerometers. For all training sessions and games, peak external workload intensities were determined using accelerometer-derived moving averages for PlayerLoad per minute (PL·min-1) across sample durations of 0.5, 1, 2, 3, 4, and 5 minutes. Linear mixed-models and effect sizes (ESs) were used to compare peak PL·min-1 between sample durations, session type, and playing role. Peak PL·min-1 was significantly different between all sample durations (p < 0.05; ES = 0.88-5.45), with higher intensities evident across shorter sample durations. In starting players, peak intensities were significantly higher during games compared with training for all sample durations (p < 0.05; ES = 0.69-0.93). Peak game intensities were higher in starting players using all sample durations (p > 0.05; ES = 0.69-1.43) compared with bench players. Shorter sample durations produced higher peak PL·min-1. Peak intensities were higher during games than training in starting players, indicating training may not adequately prepare players for the most demanding passages of game-play.

The Relationship Between Athletic Performance and Physiological Characteristics in Wheelchair Basketball Athletes

Purpose: This study was aimed to investigate the relationship between athletic performance and physiological characteristics in wheelchair basketball (WB) athletes with different classification scores. Methods: Twenty-six (24 male and 2 female) WB athletes were involved into the study. The participants were divided into two functional categories (Category A:1.0-2.5 points, category B: 3.0-4.5 points) according to the IWBF rules. Shoulder internal (IR) and external rotation (ER) muscle strengths were evaluated with the ISOMED 2000® isokinetic dynamometer. Handgrip strength was evaluated with hydraulic hand dynamometer. Custom ramp protocol on treadmill was employed to measure aerobic capacity. Anaerobic capacity was evaluated with Wingate anaerobic power test in standard laboratory conditions. The athletic performance was assessed by 20 m Sprint test, Slalom Test, and Zone Shot tests. Results: Category B athletes achieved significantly better results in the measurements of shoulder IR and ER muscle strength, aerobic and anaerobic capacity, and athletic performance while the grip strength was found similar in the categories. There was a significant correlation between the athletic performance and shoulder IR and ER muscle strength, and aerobic and anaerobic capacities in two categories. There was no significant relationship between grip strength and athletic performance parameters in two categories. Conclusion: It was concluded that athletic performance in WB athletes with different classification scores is related to upper extremity muscle strength, aerobic, and anaerobic capacity. Additionally, upper limb muscle strength, athletic performance, aerobic and anaerobic capacity assessments to be made will contribute positively to the planning of individual training and exercise programs.

The Effect of Differential Repeated Sprint Training on Physical Performance in Female Basketball Players: A Pilot Study

This pilot study aimed to determine the effects of differential learning in sprint running with and without changes of direction (COD) on physical performance parameters in female basketball players and to determine the feasibility of the training protocol. Nine female basketball players completed 4 weeks of repeated sprint training (RST) with (COD, n = 4) or without (NCOD, n = 5) changes of direction. A battery of sprints (0–10 and 0–25 m), vertical jumps (counter movement jump (CMJ), drop jump, and single-leg CMJs), and COD tests were conducted before and after intervention. NCOD completed two sets of ten sprints of 20 m, whereas COD performed 20 m sprints with a 180 degree turn at 10 m, returning to the starting line. Before each sprint, participants were instructed to provide different fluctuations (i.e., differential learning) in terms of varying the sprint. Both groups had 30 s of passive recovery between two sprints and 3 min between sets. A significant effect of time for the 0–10 m sprint, CMJ, and single leg-CMJ asymmetries were observed. Adding “erroneous” fluctuation during RST seems to be a suitable and feasible strategy for coaches to enhance physical performance in young female basketball players. However, further studies including larger samples and controlled designs are recommended to strengthen present findings.

Basketball-Specific Small-Sided Games Training during Ramadan Intermitting Fasting: Do Changes in Body Composition, Sleep Habits, and Perceived Exertion Affect Technical Performance?

The objective of this study was to assess the effects of an additional small-sided games (SSGs) training program during Ramadan intermitting fasting (RIF) on technical performance depending on changes in body composition, sleep habits, and ratings of perceived exertion (RPE). Twenty-four professional male basketball players from the Tunisian first division participated in this study. The players were randomly assigned to an intervention group (INT; n = 12) or an active control group (CON; n = 12). Both groups completed a four-week SSG training program (three sessions per week). During the first and fourth weeks of the SSGs training, the two groups were evaluated to detect changes in technical performance, dietary intake, body composition, sleep quality index (PSQI) survey outcomes, RPE, heart rate (HR), and blood lactate concentration [La]. During the fourth week of the RIF period, body composition, dietary intake, sleep latency, sleep duration, and HR significantly decreased only for INT (p < 0.001). However, RPE significantly increased (p < 0.001), and technical performances were negatively affected (p < 0.01). MANCOVA (adjusted for the percentage of change in sleep duration, body mass, and RPE) showed no significant differences in either group. In conclusion, our results showed that the technical performance of professional basketball male players was significantly affected at the end of RIF independently of changes in RPE, sleep habits, and body composition.

Lower Extremity Flexibility Profile in Basketball Players: Gender Differences and Injury Risk Identification

Analysis of the flexibility profile of basketball players (BPs) can reveal differences in range of motion (ROM) by gender and also identify those players who are at higher risk for sports injuries. A descriptive observational study was conducted to determine the lower extremity flexibility profile of sixty-four basketball players and gender differences to identify players at higher risk of injury due to limited and asymmetric ROM in one or more movements. Participants: Sixty-four (33 male and 31 female) competitive athletes from the national leagues of the Spanish basketball league system participated in the present study (power of sample size ≥0.99). The eight passive ROM tests of the hip, knee and ankle were assessed using the ROM-SPORT battery. Each player completed a questionnaire on age, basic anthropometric data, dominant extremities, and training and sport-related variables. The lower extremity flexibility profile was established at 15° and 10° hip extension (HE), 39° and 38° ankle dorsiflexion with knee extended (ADF-KE), 40° and 39° ankle dorsiflexion with knee flexed (ADF-KF), 43° and 43° hip abduction (HAB), 75° and 61° hip abduction with the hip flexed (HAB-HF), 78° and 83° hip flexion with the knee extended (HF-KE), 134° and 120° knee flexion (KF), and 145° and 144° hip flexion (HF) by male and female basketball players, respectively. Sex differences in HE, HAB-HF, and KF were observed in BPs (p ≤ 0.01; Hedges’ g ≥ 1.04). Players reported limited ROM in ADF-KF, HE, HAB-HF, HF-KE, and KF; and asymmetric ROM mainly in HE, ADF-KE, KF, ADF-KF, and HF-KE. In conclusion, this study provides gender-specific lower extremity flexibility profile scores in BPs that can help athletic trainers and athletic and conditioning trainers to identify those players who are at higher risk of injury due to abnormal ROM scores.

Influence of the Pedagogical Model and Experience on the Internal and External Task Load in School Basketball

The methodology used by the teacher in Physical Education sessions conditions the physical fitness of the students, since the design of the tasks determines the physical and physiological demands to which they are exposed. This study aimed to quantify and compare, according to the teaching methodology and students' previous experience, the external (eTL) and internal (iTL) load resulting from the application of three intervention programmes that follow different teaching methodologies to teach school basketball: the Tactical Games Approach (TGA), Direct Instruction (DI) and Service Teacher's Basketball Unit (STBU). The Ratings of Perceived Exertion (RPEs) recorded in the assessments (pre-test/post-test) were also studied. A total of 49 students, aged 11 to 12 and divided into three class groups, from the sixth grade of primary education at a state school in Spain, participated in the study. Teaching-learning programs were randomly assigned to student groups. All the sessions were monitored with inertial devices that made it possible to record physical activity and convert the information into kinematic parameters. The results indicated that during the sessions, the students who followed the TGA method recorded higher values of eTL (player load; DI = 4.92, TGA = 6.95, STBU = 2.99) and iTL (mean heart rate; DI = 142.94, TGA = 157.12, STBU = 143.98). In addition, during the evaluation tests, they presented heart rate levels similar to those obtained by the students in the other programmes. However, they spent more time doing high-intensity activity, working longer in the running (DI = 3.42, TGA = 11.26, STBU = 8.32) and sprinting speed ranges (DI = 0.00, TGA = 0.12, STBU = 0.11), and presenting better physical fitness. During the assessments, students with no prior basketball experience showed higher levels of top speed; experienced students had higher levels of heart rate. The TGA method favours the physical condition and health of primary education students, which is why this method is recommended when planning Physical Education sessions.

Sleep and Physical Performance: A Case Study of Collegiate Women's Division 1 Basketball Players

In this work, we present a case study to evaluate the connections between sleep, training load, and the perceptions of physical/emotional state of a collegiate, division 1 Women's basketball team. The study took place during the off- (3 weeks) and pre-season (6 weeks) while sleep was tracked using WHOOP wearable straps. Training load was recorded by the strength coach and athletes. Short Recovery and Short Stress (SRSS) questionnaire was used to evaluate the perceptions of athletes on their own emotional and physical states. Our results showed that heart rate measurements are associated with stress levels and recovery perception. We also discovered that the training load was not linked to the sleep variables without the considerations of athletic performance. However, training load may alter perceived stress and recovery which requires further exploration.

SARS-CoV-2 transmission during an indoor professional sporting event

Sporting events with spectators can present a risk during the COVID-19 pandemic of becoming potential superspreader events that can result in mass-infection amongst participants-both sportspeople and spectators alike. In order to prevent disease transmission, many professional sporting bodies have implemented detailed hygiene regulations. This report analyzes SARS-CoV-2 transmission during a professional sports event (2nd division professional basketball in Germany). Whilst social distancing in this context is not always possible, the rate of infection was significantly reduced by wearing face masks that cover the mouth and nose. There was no infection amongst individuals who continuously wore medical particle filter masks (Category KN95/FFP2 or higher) during this sporting event.

Current Sport Organization Guidelines From the AMSSM 2019 Youth Early Sport Specialization Research Summit

CONTEXT

Youth athletes may be at elevated risk for adverse health due to sport specialization. Sport organizations have developed guidelines for participation during growth and development.

OBJECTIVE

To assess youth sport development guidelines using a 15-item framework across sport organizations and governing bodies in soccer, basketball, ice hockey, and swimming.

DATA SOURCES

English-language results from January 1, 2000, to December 31, 2018, from published sport organization guidelines and athlete development plans.

STUDY SELECTION

Two investigators independently reviewed publications identified from sport organizations. A total of 23 guidelines were incorporated, including 5 general sport organizations and 18 sport-specific guidelines.

STUDY DESIGN

Systematic review.

LEVEL OF EVIDENCE

Level 4.

DATA EXTRACTION

Two investigators independently identified all recommendations that fit within a predetermined rubric of recommendations encompassing 4 domains: Psychological Development/Approach, Physical Development/Load, Facilities and Resources, and Timing and Monitoring of Specialization. Sport-specific guidelines on volume were summarized.

RESULTS

Sport organizations and sport-specific guidelines had consensus on 2 items out of the 15-item: emphasis on early skill development and access to well-trained coaches. While recommended by all sports organization, multisport participation was emphasized by 3 of 4 sports, excluding soccer. Volume recommendations were inconsistent between and within sports. No group proposed methods to monitor athlete well-being.

CONCLUSION

This review highlights areas of agreement within sport organizations and governing bodies. Creating a framework to guide youth sport specialization may lead to specific and consistent guidelines.

Construct Validity and Reliability of a New Basketball Multidirectional Reactive Repeated Sprint Test

The objective of this study was to investigate the construct validity and reliability of a new reactive multidirectional repeated sprinting test (RRSA_5COD) in basketball players. Forty male basketball players were divided into two groups: Professional (PRO; n = 20) and Semi-professional (SEMI; n = 20). Participants completed the yo-yo intermittent recovery test level 1 (Yo-YoIR1), the squat jump (SJ), the counter movement jump (CMJ), the single leg drop jump (DJ), the 20-m sprint test, the planed multidirectional repeated sprinting test (PRSA_5COD), and the RRSA_5COD test. Reaction time (RT) and movement time (MT), total time (TT), best time (BT), and fatigue index (FI) were assessed. Heart rate (HR) was continuously recorded, while rating of perceived exertion (RPE) and blood lactate concentration (LA) were measured post-tests. The reliability of the RRSA_5COD test was also assessed between two attempts with one week between them. The RRSA_5COD results demonstrated to be reliable with most of the variables showing ICC > 0.80. BA Bonferroni post hoc revealed a significant better TT in favor of RRSA_5COD (p < 0.001; ES = 0.15; small), and in favor of PRO (p < 0.001; ES = 0.006; small). The result showed a significant better performance in favor of PRO in all physical fitness tests. In conclusion, it was found that the RRSA_5COD discriminates between professional and semi-professional male basketball players, and the results were demonstrated to be reliable.

Evidence of Widespread Mechanical Hyperalgesia but Not Exercise-Induced Analgesia in Athletes With Mild Patellar Tendinopathy Compared With Pain-Free Matched Controls: A Blinded Exploratory Study

OBJECTIVE

The aim of the study was to assess centrally induced pain processing with pressure pain thresholds bilaterally and remotely in active volleyball and basketball athletes with mild patellar tendinopathy compared with asymptomatic control athletes. Secondary objective was to explore the role of exercise-induced analgesia during a training session in athletes with patellar tendinopathy.

DESIGN

In this exploratory study, pressure pain thresholds of 21 patellar tendinopathy athletes and 16 age- and sex-matched asymptomatic team members were measured by a blinded assessor bilaterally on the patellar tendon and unilaterally on the elbow extensor tendon with a pressure algometer before, during, and after a regular training session.

RESULTS

Patellar tendinopathy athletes had a significantly higher average body mass index compared with asymptomatic athletes (mean difference 1.75 kg/m2; 95% confidence interval = 0.35-3.15, P = 0.02). At baseline, athletes with patellar tendinopathy showed lowered pressure pain thresholds in the affected knee (P = 0.001), unaffected knee (P < 0.001), and elbow (P = 0.01) compared with controls. No clear patterns were identified to explain between-group differences in pressure pain thresholds before, during, and after exercise.

CONCLUSIONS

This exploratory study found primary and secondary mechanical hyperalgesia in athletes with patellar tendinopathy compared with asymptomatic athletes. Further research is required on the effects of an acute exercise bout on pain thresholds in this population.

Descriptive and Kinetic Analysis of Two Different Vertical Jump Tests Among Youth and Adolescent Male Basketball Athletes Using a Supervised Machine Learning Approach

ABSTRACT

Gillett, J, De Witt, J, Stahl, CA, Martinez, D, and Dawes, JJ. Descriptive and kinetic analysis of two different vertical jump tests among youth and adolescent male basketball athletes using a supervised machine learning approach. J Strength Cond Res 35(10): 2762-2768, 2021-The countermovement jump (CMJ) is a functional movement in basketball and is also frequently used as an assessment of lower-body power. The CMJ can be performed in a variety of manners, and multiple variables can be extracted, and calculated, from the ground reaction force (GRF) time curve. The purpose of this article is to present kinematic and kinetic data collected from adolescent male basketball players during performance of the CMJ with hands on hips (HOH) or with an arm swing while reaching overhead to a target (i.e., vertical jump reach [VJR]). This study also sought to determine the effectiveness of a machine learning algorithm to identify the most important features that relate to jump height. Bilateral GRF data were collected on 89 right-handed male basketball athletes (age: 13.19 ± 0.72 year old, mass: 60.44 ± 13.35 kg, standing reach height: 228.49 ± 16.79 cm) using force platforms (Forcedecks, Vald Performance, Newstead, Queensland, Australia) and their associated software. Fifty-six bilateral kinematic and kinetic variables from each condition were analyzed using supervised machine learning to identify the top 10 important features to predict jump height in each condition, and to predict VJR height using HOH data. Vertical center of mass flight height was greater during VJR trials than during HOH trials (38.9 ± 6.8 cm vs. 32.6 ± 5.5 cm, respectively). The only common predictor variables between the conditions were concentric impulse and peak power. HOH jump data were able to predict VJR height with a mean error of 7.13 cm. These data suggest that important force platform data relating to jump height differ depending on test condition, and that data from CMJ performed with HOH, particularly peak power, concentric impulse, and concentric rate of power development, can be used to predict jump height during functional performance.

Are synergies continuously present in cyclical movements? An example with the basketball dribble task

In human movement, synergies occur when two or more variables co-vary to stabilize a performance goal. The concept of motor redundancy is associated with the existence of several strategies to complete the same task, which enables a movement system to adapt to an ever-changing environment. This feature provides the system with the ability of being flexible enough to produce adaptive movements, but also stable enough to produce acceptable outputs which is a key issue in motor performance. In a kinetic chain of movement, two proximal joints might reciprocally compensate to stabilize an end-effector (i.e., the most distal segment in the limb that interacts with the environment). End-effector variables are 'controlled', and directly linked to performance, whereas the task relevant elements are allowed by the system to have high variability, providing adaptability. In basketball dribbling, we hypothesized that shoulder and elbow variability contributes to stabilize the dribble height as an end-effector performance variable. A specific computational procedure based on the UCM (i.e., Uncontrolled Manifold) notion was used to capture synergies in two groups according to the experience level: amateurs and professionals. Results identified synergy presence during the basketball dribbling, which only occurred when the wrist reached its peak height. The control of the wrist peak height is achieved due to a reciprocal compensation between shoulder and elbow which stabilizes the dribbling height.

CNN-LSTM Hybrid Model for Kinematic Feature Analysis and Parabolic Radian Prediction in Basketball Videos

With the improvement of living standards around the world, people's love for sports has also increased; basketball is especially loved by people. It is of great importance to provide sound motor instruction for basketball. To this end, this paper comprehensively investigates the dependence between the optimal release conditions and the corresponding shooting arm movements in basketball players. We carry out kinematic feature analysis of basketball sports videos, propose a hybrid CNN-LSTM model that can predict the arc of the shooting parry, and identify the key movements of the arm joint that produce optimal release velocity, angle, and backspin in short-, mid-, and long-range shots. The experiment demonstrates that the model has three rigid planar links with rotational joints that mimic the shoulder, elbow, and wrist joints of the upper arm, forearm, and hand, which are better at guiding the optimal ball release speed, angle, and backspin for different players with the fastest ball speed being about 4.6 m/s and the slowest being about 1.7 m/s.