Background In the context of the ageing of the French population, physical activity becomes a principal means for maintaining good health. International organisations are thus giving increasing importance to physical activity in programmes of disease-prevention. In parallel with these concerns, studies have shown the impact of sedentary activities (in particularly as a result of the seated position and screen time) on health. Objective To show the links between physical activity, sedentarism and health indicators and to identify the socio-demographic variables by which they are influenced (particularly gender). Study design This is a transversal epidemiological study conducted among the French population between 2014 and 2016 by Santé publique France, the national public health agency. Methods The RPAQ (Recent Physical Activity Questionnaire) was used to measure the physical activity and sedentary lifestyle of individuals. The analyses focus on the behaviours among the population of older adults (55–74 years old, n = 1155). Results A third of French older adults does not meet the WHO recommended physical activity levels, particularly so among women. The results of this survey point to significant links between health indicators (especially overweight and obesity) and the physical activity level and sedentarity of older adults. From the age of 60, energy expenditure linked to physical activity increases before decreasing from the age of 65. Older adults spend almost 6 hours per day in sedentary activities. The combinations between physical activity and sedentarism highlight four profiles of older adults. The most active profile is the one with the best health indicators. Conclusion The links between health, sedentarity and physical activity are unequivocal: people who achieve the WHO recommendations for physical activity and spend less than 7 hours each day in sedentary activities are those who also have the best health indicators. These results vary with sociographic characteristics and reveal significant links with health indicators.