The association between television viewing and overweight among Australian adults participating in varying levels of leisure-time physical activity.
OBJECTIVE
To investigate the effect of physical activity on the association between television viewing and overweight (body mass index (BMI) > or =25 kg/m2).


METHODS
Cross-sectional study administered by interview to adults randomly selected from the electronic white pages.


METHODS
3392 adults (64% response rate) from a representative population sample in the State of New South Wales, Australia.


METHODS
Self-reported height and weight, two-week leisure-time physical activity recall, one-week average television viewing recall.


RESULTS
BMI and physical activity patterns were both associated with hours of television watched. Compared to those participants who reported watching less than one hour of television per day, those watching 1 to 2.5 hours were 93% more likely to be overweight (BMI>/=25 kg/m2), those watching 2.5 to 4 hours were 183% more likely to be overweight, those watching more than 4 hours per day were four times more likely to be overweight. Physical activity was not directly associated with being overweight, but an interaction between activity and television watching was present. Respondents in the low, moderate and high physical activity categories who reported watching more than 4 hours of television per day were twice as likely to be overweight compared to those who watched less than one hour of television per day, irrespective of physical activity participation.


CONCLUSIONS
With approximately half the Australian adult population overweight or obese, these findings indicate that public health strategies to reduce overweight and prevent weight gain may need to focus on reducing sedentary behaviours such as television viewing in addition to increasing physical activity.
Salmon
J
J
School of Health Sciences, Deakin University, 221 Burwood Hwy, Burwood, Victoria 3125, Australia.
Bauman
A
A
Crawford
D
D
Timperio
A
A
Owen
N
N
D000293:Adolescent; D000328:Adult; D001315:Australia; D001827:Body Height; D015992:Body Mass Index; D001835:Body Weight; D015444:Exercise; D005260:Female; D006801:Humans; D008019:Life Style; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000523:psychology*; D013690:Television