There is a close relationship between lifestyle behaviors and excess adiposity. Althoughbody mass index (BMI) is the most used approach to estimate excess weight, other anthropometricindices have been developed to measure total body and abdominal adiposity. However, littleis known about the impact of physical activity and adherence to a Mediterranean diet on theseindices. Here we report the results of a cross-sectional study with 6672 middle-aged subjects withlow to moderate cardiovascular risk from the Ilerda Vascular (ILERVAS) project. The participants’adherence to physical activity (International Physical Activity Questionnaire short form) and MedDiet(Mediterranean Diet Adherence Screener) was evaluated. Measures of total adiposity (BMI, ClínicaUniversidad de Navarra-Body Adiposity Estimator (CUN-BAE), and Deurenberg’s formula), centraladiposity (waist and neck circumferences, conicity index, waist to height ratio, Bonora’s equation,A body adiposity index, and body roundness index), and lean body mass (Hume formula) were assessed. Irrespective of sex, lower indices of physical activity were associated with higher valuesof total body fat and central adiposity. This result was constant regardless of the indices used toestimate adiposity. However, the association between MedDiet and obesity indices was much lessmarked and more dependent on sex than that observed for physical activity. Lean body mass wasinfluenced by neither physical activity nor MedDiet adherence. No joint effect between physicalactivity and MedDiet to lower estimated total or central adiposity indices was shown. In conclusion,physical activity is related to lower obesity indices in a large cohort of middle-aged subjects. MedDietshowed a slight impact on estimated anthropometric indices, with no joint effect when consideringboth lifestyle variables. ClinTrials.gov Identifier: NCT03228459.