Purpose: The authors applied a multidimensional conceptual lens that incorporated physical, emotional, social, intellectual and spiritual health dimensions to explore pre-adolescent children's understanding of health and what it means to be healthy. Design/methodology/approach: Forty-six children aged 9-11 years old completed a short questionnaire about their understanding of health and what it means to be healthy. Data analysis was completed through a deductive analysis applying a multidimensional conceptual lens and an inductive thematic analysis of the content of children's responses to each question. Findings: The analysis of children's understandings of health and being healthy both revealed five common themes--Being well, physically active, fit and healthy; Healthy eating and body composition; Physical activity examples; Physical activity characteristics; and Unsure or ambiguous. Across both questions the majority of responses reflected the physical dimension of health, with only a few references to the social and emotional dimensions. There was no evidence of the intellectual or spiritual dimensions of health in children's responses to either question. Practical implications: The authors' data suggest that the plateau in adolescent UK children's trajectory of understandings originates earlier in childhood, with children aged 9-11 showing a similarly limited understanding of health and being healthy as UK adolescents. Moreover, this focus on the physical dimension is narrower than previously considered as it is restricted to the movement category of this dimension only. Originality/value: The authors' findings have implications for the timing and focus of health education interventions for children.