Constraints such as the 'ethic of care' have been identified as significant impediments to mother's ability to prioritise their own physical activity (PA) needs over domestic responsibilities. However, recent research has suggested that women's 'ethic of care' also extends to the assumption of responsibility for the health and PA levels of their children and family. Drawing on a governmentality approach informed by feminism we contend that neo-liberal rationalities that underpin health initiatives have the potential to negate the 'benefits' women may experience through engaging in PA. Using research conducted in Australia, we found that although setting an example as a 'healthy mother' often provided the legitimacy for women to participate in PA, many women experienced a 'burden of care'. This resulted in self-blame and negative surveillance as mothers struggled to action and realise outcomes that would satisfy current health policy imperatives.