Reference Values for the Muscle Power Sprint Test in Children Aged 5-12 Years

SUMMARY Rationale: Children with congenital abnormalities face risks of below-average lung function and exercise tolerance (1-3). As the standard of care, our tertiary hospital enrolls these children in a prospective, longitudinal follow-up program from birth (4). This program involves regular assessments of overall health and development, including spirometry and exercise tolerance tests conducted by pediatric physiotherapists. Historically, the Bruce treadmill protocol was employed for testing maximal exercise tolerance in children aged 4 and above, but it presented limitations such as high muscular demands of the steep inclines and large workload increments, impacting reliability and potentially causing premature discontinuation (5).

In response, the Bruce protocol was replaced in newer follow-up program versions by the Muscle Power Sprint Test (MPST). Unlike the Bruce protocol, which assesses aerobic capacity, the MPST focuses on anaerobic exercise capacity, which is crucial for children's daily activities like playing with peers (6). Performing the MPST involves six short runs of 15 meters, from which the calculated 'mean power' serves as the primary outcome. The distance covered during these runs corresponds well to the distances children cover during daily play activities.

While Dutch norm values for children aged 6-18 exist, gathered mainly in rural areas between 2012 and 2016, the study highlights the need for updated reference values. Lifestyle changes, exacerbated by the Covid-19 pandemic, underscore the urgency of updating exercise tolerance reference values (7). Notably, there is a current lack of established reference values for 5-year-olds undergoing MPST testing in our longitudinal follow-up program, emphasizing the need for comparative data in this age group.

Objective: Our primary goal is to establish reference values for the MPST for primary school children aged 5-12 belonging to a diverse population living in the Netherlands.

Study design: The study adopts a prospective cross-sectional design.