This study assessed the impact of life coaching on physical activity participation, self-efficacy, social support, and perceived behavioural control among physically inactive youth between the ages of 12 and 14 years in London, Ontario. The multiple-baseline across participants single case-experimental design study consisted of five 12 to 14 year olds. Six coaching sessions were conducted over two months by a certified professional Co-active coach. Physical activity increased for one participant while the other participants’ physical activity remained unchanged. No significant changes occurred in self-efficacy, social support, and perceived behavioural control with specific regard to becoming more physically active. Results indicted no consistent intervention effects for physical activity. Furthermore, coaching may not be appealing to youth of this age group given the difficulties experienced obtaining the necessary number of participants and the low levels of participant commitment throughout the study.