The idea that proficiency in the fundamental movement skills (FMS) is necessary for the development of more complex motor skills (i.e., the proficiency barrier) and to promote health-enhancing physical activity and health-related physical fitness levels is widespread in the literature of motor development. Nonetheless, to the best of our knowledge, there is no study assessing whether children presenting proficiency below a specified proficiency barrier would demonstrate difficulty in improving performance in more complex skills—even when subjected to a period of practice in these complex skills. The present study tested this. Eighty-five normal children (44 boys) aged 7 to 10 years participated in the study. The intervention took place during 10 consecutive classes, once a week, lasting 40 min each. Six FMS (running, hopping, leaping, kicking, catching and stationary dribbling) and one transitional motor skill (TMS) (speed dribbling skill) were assessed. The results showed that only those who showed sufficient proficiency in running and stationary dribbling before the intervention were able to show high performance values in the TMS after intervention. In addition, in line with recent propositions, the results show that the basis for development of the TMS was specific critical components of the FMS and that the barrier can be captured through a logistic function. These results corroborate the proficiency barrier hypothesis and highlight that mastering the critical components of the FMS is a necessary condition for motor development.

Purpose: In 1979 Vern Seefeldt postulated that individuals that did not achieve a given level of proficiency in the fundamental movement skills (FMS) would be limited in performance on new and more complex skills during development. This hypothesis, the proficiency barrier, inspired research in motor development but, to the best of our knowledge, was never empirically tested. The present article tested three potential mathematical functions (linear, sigmoidal and piecewise) describing the proficiency barrier relating FMS with a transitional movement skill (TMS, a more complex movement skill). Methods: 87 children aged 7 to 10 years were tested on six skills of the TGMD-2 test battery (running, hopping, leaping, kicking, catching and stationary bouncing) and dribbling (a combination of running and stationary bouncing). Results: The results showed evidence for the proficiency barrier based on a specific sigmoidal relation. We also identified critical movement aspects from FMS that seem to induce this relation. Conclusion: There is some evidence supporting Seefeldt’s Proficiency Barrier.

Judo is currently the most practiced combat sport in the world. There is no doubt of its importance for children, adolescents, adults, and seniors. However, due to its inherent complexity, coaches tend to place greater or lesser emphasis only on one of its multiple domains during the judoka formative years. The present study presents a novel developmental approach signaling Judo as an excellent way for physical, motor, educational, and health development across the lifespan. In this study, we consulted 23 Judo coaches, aiming to clarify the relevance and adequacy of the domains (Competitive, Health, Technical-Tactical, and Philosophical-Educational) and phases of the proposed model. Our findings showed that the model contents—physical, motor, educational, and health—are entwined with its four domains, which were considered of utmost importance by experts in the development of judokas. We, therefore, contend that our model is essential to better understand the growth and development of young judokas. Also, it may be a useful tool for Motor Development experts.

Objectives: The REACT project was designed around two main aims: (1) to assess children's growth and motor development after the COVID‐19 pandemic and (2) to follow their fundamental movement skills' developmental trajectories over 18 months using a novel technological device (Meu Educativo®) in their physical education classes. In this introductory article, the first of the Journal's special issue dedicated to REACT, our goal was to present the project rationale, its methodology, training and certification of the team, statistical approach, quality control, governance, and study management.Methods: We sampled 1000 children (6–10 years of age) from 25 of the 32 primary schools in Matosinhos, northern Portugal. The protocol included a set of variables clustered around the child (growth, physical fitness, fundamental movement skills, and health behaviors), family (demographics, socioeconomic status, parental support for sports participation and physical activity), school (policies and practices for health behaviors, infrastructure for physical education and sports practices), and neighborhood and home environments (safety, sidewalks, sports facilities, as well as children electronic devices and play equipment at home). A set of standard protocols were implemented in REACT together with a rigorous system of training and certification of all members of the research team. This was complemented with a pilot study to assess, in loco, the quality of data acquisition, data entry, and control.Discussion: Results from REACT will provide school administrators and teachers with novel and far‐reaching information related to children's growth and motor development as well as health behaviors after the COVID‐19 pandemic. It will also provide city‐hall education officials with insight regarding children's physical fitness, fundamental movement skills, and sports practices that will be of great importance in devising novel intervention programs to increase health‐enhancing physical activity, and combat sedentariness and obesity. Finally, it will offer parents a wealth of information regarding their children's growth, motor development, and health.

Data relating physical performance to the timing of the adolescent growth spurt are limited. Aim: This study identifies: (i) age-at-peak height velocity (APHV), (ii) physical performance spurt patt...