AUTHOR=Popovic Stevo , Sarmento Hugo , Demetriou Yolanda , Marques Adilson TITLE=Editorial: Monitoring and Promoting Physical Activity and Physical Fitness in Children JOURNAL=Frontiers in Public Health VOLUME=9 YEAR=2021 URL=https://www.frontiersin.org/journals/public-health/articles/10.3389/fpubh.2021.633457 DOI=10.3389/fpubh.2021.633457 ISSN=2296-2565