Modelling the dynamics of change in the technical skills of young basketball players: The INEX study

Comparison of physical activity, sedentary time, and physical fitness among Chinese children and adolescents in Qinghai between 2019 and 2023

This study aimed to assess the differences in physical activity and physical fitness in 2019 and 2023 among children and adolescents in Qinghai Province. Data were collected from the Chinese National Survey on Student Constitution and Health (CNSSCH) in 2019 and 2023. The study ultimately included 13,296 participants (5,039 in 2019 and 8,257 in 2023) aged 6-22, including primary, middle, and high school students in Qinghai Province, China. Physical fitness assessments included height, weight, vital capacity, sit-and-reach distance, pull-ups, timed sit-ups, standing long jump, 50-meter dash, 800-meter run, 1000-meter run, 50 m × 8 shuttles run, and timed rope-skipping. Independent samples T-tests and multiple linear regression analyses were employed to explore differences and associations in moderate-to-vigorous physical activity (MVPA), sedentary time (SED), and physical fitness in this population in 2019 and 2023. Compared to 2019, children and adolescents measured in 2023 showed a significant increase in MVPA and a significant decrease in SED. Vital capacity improved significantly across all academic stages, with primary school girls showing improved performance in the 50 × 8 shuttles run. Secondary school students significantly declined in their performance in 800 m and 1000 m runs. Standing long jump performance improved for middle and high school students, while pull-ups declined for high school boys. Timed sit-ups declined for middle school girls, with no significant changes at primary and high school. Flexibility improved for high school boys and both middle and high school girls but decreased for primary school boys and girls, as well as for middle school boys. Timed rope-skipping was measured only in primary school students, and it improved significantly. Speed performance, measured by the 50 m dash, improved in primary school students but declined in middle and high school students. Regression analysis revealed that MVPA was positively associated with vital capacity, 800 m running, standing long jump, pull-ups, and timed sit-ups, while negatively associated with 1000 m running, timed rope-skipping, and 50 m dash. SED was positively associated with 800 m and 1000 m running performance and timed sit-ups. Our study highlights distinct trends in physical fitness across school stages, and sex associations of MVPA and SED with fitness outcomes underscore the need for tailored, region-specific health strategies in high-altitude, underdeveloped areas.

Action Recognition in Basketball with Inertial Measurement Unit-Supported Vest

In this study, an action recognition system was developed to identify fundamental basketball movements using a single Inertial Measurement Unit (IMU) sensor embedded in a wearable vest. This study aims to enhance basketball training by providing a high-performance, low-cost solution that minimizes discomfort for athletes. Data were collected from 21 collegiate basketball players, and movements such as dribbling, passing, shooting, layup, and standing still were recorded. The collected IMU data underwent preprocessing and feature extraction, followed by the application of machine learning algorithms including KNN, decision tree, Random Forest, AdaBoost, and XGBoost. Among these, the XGBoost algorithm with a window size of 250 and a 75% overlap yielded the highest accuracy of 96.6%. The system demonstrated superior performance compared to other single-sensor systems, achieving an overall classification accuracy of 96.9%. This research contributes to the field by presenting a new dataset of basketball movements, comparing the effectiveness of various feature extraction and machine learning methods, and offering a scalable, efficient, and accurate action recognition system for basketball.

Are There Sensitive Periods for Skill Development in Male Adolescent Basketball Players?

PURPOSE

Although spurts in physical capacities during adolescence are well known, little is known about the existence of such spurts in sport-specific skill development, especially during the period of rapid growth in stature. Our aims were to examine the timing, intensity, and sequence of basketball-specific skill spurts aligned with biological (years from peak height velocity (PHV)) rather than chronological age. We then defined putative sensitive periods (windows of optimal development) for each skill aligned to the adolescent growth spurt.

METHODS

Altogether, 160 adolescent male basketballers aged 11-15 yr were tested biannually over 3 consecutive years. The years from attainment of PHV was estimated, and six skill tests were aligned to each year from PHV in 3-month intervals. Skill velocities were estimated using a nonsmooth polynomial model.

RESULTS

Maximal gains in slalom dribble occurred 12 months before PHV attainment (intensity, 0.18 m·s -1 ·yr -1 ), whereas in speed shot shooting (intensity, 9.91 pts·yr -1 ), passing (intensity, 19.13 pts·yr -1 ), and slalom sprint (intensity, 0.19 m·s -1 ·yr -1 ), these skill spurts were attained 6 months before PHV attainment. The mean gains in control dribble (intensity, 0.10 m·s -1 ·yr -1 ) and defensive movement (intensity, 0.12 m·s -1 ·yr -1 ) peaks coincided with attainment of PHV. We identified different sized windows for optimal development for each skill.

CONCLUSIONS

Peak spurts in skill development, for most basketball skills, were attained at the same time as PHV. The multiple peaks observed within the defined windows of optimal development suggest that there is room for skill improvement even if gains might be greater earlier rather than later in practice. Our findings highlight the need to make coaches aware of where their players are relative to the attainment of PHV because different skills appear to develop differently relative to PHV. Such knowledge may help in designing more relevant training regimes that incorporate the athlete's current growth status so that skill development can be maximized.

The effects of body size and training environment on the physical performance of adolescent basketball players: the INEX study

BACKGROUND

Although adolescent basketballers differ in body size, shape, and composition, less is known about how these factors interact during physical development.

AIM

We used ontogenetic allometry to identify the optimal body size and shape characteristics associated with physical performance in adolescent basketball players, and investigated the effects of training experience, training volume, maturity status, and club characteristics on physical performance development.

SUBJECTS AND METHODS

Two hundred and sixty-four male basketballers, from five age-cohorts (11-15 years of age), were followed consecutively over three years. Three physical performance components, anthropometrics, training information, and biological maturation were assessed bi-annually. Longitudinal multiplicative allometric models were developed.

RESULTS

Players with a physique that had a dominant ectomorphic component performed better in all physical performance components. When adjusting for confounders other than size, the development of running speed was independent of body size. Players advanced in maturation were physically fitter. Training data had no significant effect on developmental trajectories of running speed or lower body explosive strength. Club characteristics had no significant association with any physical performance trajectories.

CONCLUSION

Leaner players have advantages in physical performance and individual characteristics play an important role, over and beyond club structure, in developing physical performance.

Physiological Responses and Technical-Tactical Performance of Youth Basketball Players: A Brief Comparison between 3x3 and 5x5 Basketball

This study aims to examine youth players' physiological responses and technical-tactical performance when playing simulated 3x3 and 5x5 basketball games. Fifteen well-trained male basketball players (16.6 ± 0.2 years old) participated in scrimmage basketball games under two different conditions: 3x3 (half-court) and 5x5 (full-court). The players' heart rate, muscle oxygen saturation and total hemoglobin data were collected and computed to describe physiological responses, while video analysis was used to characterize their technical-tactical performance. A Bayesian one-way analysis of variance (ANOVA) was used to quantify the predictive influence of both game conditions on the physiological and the technical-tactical variables. The results indicated that different game conditions influenced the players' physiological responses slightly, as only hemoglobin sample entropy increased between the 3x3 and 5x5 game scenarios. Conversely, statistical differences in most of the technical-tactical variables were moderate and decisive in favour of the game condition model. Overall, this study emphasizes that playing 3x3 and 5x5 basketball games lead to relatively negligible differences in the players' physiological response but pronounced variations in their technical-tactical performance. Therefore, important implications may be drawn to the applied field as the specificity of technical-tactical adaptations when playing 3x3 or 5x5 formats should be considered by basketball coaches to better design the training sessions for players that fall within our sample age category.