Background Television (TV) viewing has been associated with obesity although the effects of specific TV content on health and other behaviours remains unknown. We examined the association between watching sport on TV, physical activity levels, and risk of obesity. Methods We studied 6,733 (aged 64.9 ± 9.2 yrs) men and women from the English Longitudinal Study of Ageing, a prospective study of community dwelling older adults. Data were collected on self reported TV time and content, and physical activity. Nurses measured height and weight for the calculation of body mass index. Results On average, participants reported viewing TV for 5.3 ± 4.1 hours per day and 30.3% of the sample watched sport on TV at least twice a week. There was no association between watching sport and physical activity levels. Participants that watched sports every day were at higher risk of obesity [odds ratio = 1.39, 95% CI, 1.15, 1.68) after adjustment for age, sex, smoking, alcohol, physical activity, total TV time, disability, and self-rated health. Conclusions Watching elite athletes may have no role in the promotion of physical activity in older adults, which has implications for staging large sporting events with physical activity legacy promises.