The physical activity pandemic is of particular concern with regard to children. Catherine Elliot of Lincoln University, New Zealand, Lee Stoner of Massey University, New Zealand, Michael Hamlin of Lincoln University and Mark Stoutenberg of the University of Miami, USA, consider the role of primary healthcare in the fight against childhood physical inactivity and obesity .Despite continued attention from health and government agencies across the globe, the physical inactivity pandemic continues to spread. This worrying trend is of particular concern with regards to children, who require regular physical activity to determine their optimal phenotype and prevent the early onset of lifestyle-related, cardio-metabolic diseases, of which obesity has garnered the most attention.[1] A recent meta-analysis by Stoner et al.[2] reported that physical activity is effective for promoting weight loss and improving cardio-metabolic health in overweight and obese adolescents. Stoner and colleagues also discuss the important role of general practitioners (GPs) in the fight against childhood physical inactivity and obesity.The American College of Sports Medicine (ACSM), through their Exercise is Medicine® (EIM) initiative, has made a call for physical activity to be considered by all GPs as a vital sign in every patient visit.[3] The EIM paradigm goes beyond pharmacotherapies to provide a more fully integrated system by implementing exercise prescriptions in healthcare systems. Prescribing exercise can manage a major cause of the root of these cardio-metabolic problems (i.e. physical inactivity) as opposed to pharmaceuticals which address only the resultant symptoms. Considering that New Zealand is a relatively contained industrialised country with high obesity rates[4] and a closed national healthcare system, the remainder of this article will discuss the possibility of EIM being uniformly instituted. Specifically, the discussion will focus on three important considerations: (1) the appropriate amount and form of exercise prescription, (2) the appropriate outcomes for monitoring success and (3) the medical education required for prescribing exercise and referring to an exercise specialist.[Image omitted: See PDF.]Appropriate Amount and Form of Exercise PrescriptionThe World Health Organization (WHO) recommends 6-17 year old children engage in at least 60 min of moderate-to-vigorous intensity physical activity (MVPA) every day.[5] In New Zealand, only 10% of secondary school students met these recommendations in 2012.[6] This low attainment rate may be at least partially attributable to the 'one-size-fits-all approach' to exercise prescription. For example, due to physical and cardiovascular constraints, obese children may experience discomfort and pain when engaging in conventional MVPA. However, resistance training has been shown to be well-tolerated by this population, and recent research suggests that high-repetition resistance training, combined with low-intensity aerobic exercise and behavioural modification, is the most effective exercise paradigm for improving body composition.[7] Furthermore, a recent study reported that obese individuals with high-strength fitness exhibit cardio-metabolic risk profiles similar to normal-weight, fit individuals.[8] Additional investigations are required to further confirm these exploratory findings in obese children and to determine how exercise prescription can best accommodate their needs.Appropriate Outcomes for Monitoring SuccessBody mass index (BMI) is commonly used by GPs to monitor changes in health; however, it is imperfectly associated with body composition, particularly among children,[9] and not necessarily an indicator of cardio-metabolic health. Among children, emerging evidence exists that cardiorespiratory fitness is a more indicative correlate of cardio-metabolic health than BMI,[10] suggesting its suitability as a vital sign for health. …