This study investigated the potential impact of a motor skill proficiency barrier on measures of cardiorespiratory (CRF) and musculoskeletal (MSF) fitness in youth. A sample of 241 youth (114 girls) aged 10 -18 years, completed the Motor Competence Assessment battery with composite scores indexed according to age-and gender-adjusted percentile scores. Motor competence (MC) levels were categorized as low (≤ 25 %tileproficiency barrier), moderate (≥ 26 %tile to < 75 % tile ), and high (≥ 75 %tile ). CRF levels (Health Risk, Needs Improvement, and Healthy) were assessed using the Fitnessgram® 20 m PACER test. Low (≤ 20 %tile ), moderate (≥ 21 %tile to ≤ 80 % tile ), and high (≥ 80 %tile ) MSF levels were assessed using grip strength normative data. Two 3 × 3 chi-square tests were conducted to determine the probability of MC level predicting CRF and MSF levels. Results demonstrated statistically significant models for performance on both the PACER (χ 2 [4, N = 241] = 22.65, p < .001) and grip strength (χ 2 [4, N = 241] = 23.95, p < .001). Strong evidence of a proficiency barrier impacting CRF was noted, as no low skilled youth met the "Healthy" fitness zone standards for PACER performance. Evidence supporting a barrier with grip strength was not as strong, as 20.8% of youth exhibiting low MC displayed high grip strength. However, all individuals with high levels of MC demonstrated at least moderate grip strength. Results emphasize the importance of developing MC during childhood as it may provide a protective effect against unhealthy CRF and MSF across youth.
Highlights. These data support the notion of Seefeldt's (1980) proficiency barrier as it relates to CRF, as no youth demonstrating low MC met the healthy fitness zone criteria for PACER performance. The development of MC may both directly and indirectly provide a protective effect against unhealthy CRF levels across childhood and adolescence. . Evidence supporting a proficiency barrier with MSF as measured by grip strength was not as strong; however, all individuals with high levels of MC demonstrated at least moderate grip strength. Thus, the development of MC may be a protective factor to mitigate low levels of MSF via enhanced neuromuscular function. . Promoting the development of MC in a variety of developmentally appropriate activities and settings (e.g. MC skills practice, structured and unstructured play, and performance contexts) is important to promote positive trajectories of CRF and MSF across childhood and adolescence.