Associations of leisure-time internet and computer use with overweight and obesity, physical activity and sedentary behaviors: cross-sectional study.
BACKGROUND
Internet and computer use are increasingly common leisure-time sedentary behaviors, which have the potential to impact negatively on health outcomes. However, little is known about the extent to which adults' Internet and computer use is associated with weight status and time spent in leisure-time physical activity.


OBJECTIVE
The objective is to examine associations of leisure-time Internet and computer use with overweight and obesity, leisure-time physical activity, and other sedentary behaviors.


METHODS
Participants (2650 adults living in Adelaide, Australia) completed a mail-back questionnaire including items on their height and weight, past seven day recall of leisure-time physical activity, Internet and computer use, and other leisure-time sedentary behaviors. Leisure-time Internet and computer use was categorized into no use, low use (less than three hours per week), or high use (three hours or more per week).


RESULTS
Participants with low leisure-time Internet and computer use had the highest levels of educational attainment and employment, and engaged in less other sedentary behaviors when compared to participants with no or high Internet and computer use. Multinomial logistic regression, adjusted for gender, age, employment, education, other sedentary behaviors and physical activity, determined that participants with a high leisure-time Internet and computer use were 1.46 (95% CI = 1.10 - 1.93) times more likely to be overweight (BMI> or =25 and < 30 kg/m(2)) and 2.52 times more likely (95% CI = 1.82 - 3.52) to be obese (BMI> or =30 kg/m(2)), compared to those who reported no Internet and computer use in their leisure-time. Adults with high leisure-time Internet and computer use were more likely to be overweight or obese even if they were highly active in their leisure time (OR = 1.86; 95% CI = 1.21 - 2.88), as compared to participants who did not use the Internet or computer. Leisure-time physical activity levels were largely independent of Internet and computer use.


CONCLUSIONS
These findings suggest that, apart from nutritional and physical activity interventions, it may also be necessary to decrease time spent in sedentary behaviors, such as leisure-time Internet and computer use, in order to reduce the prevalence of overweight and obesity. Future Internet interventions to reduce weight or increase physical activity may need to differentiate between participants with different levels of Internet use in order to increase their effectiveness. Longitudinal studies are required to examine further the potential causal relationships between the development of overweight and specific sedentary behaviors such as Internet and computer use.
Vandelanotte
Corneel
C
Institute for Health and Social Sciences Research, Central Queensland University, Rockhampton, Australia. c.vandelanotte@cqu.edu.au
Sugiyama
Takemi
T
Gardiner
Paul
P
Owen
Neville
N
D000328:Adult; D001315:Australia; D015992:Body Mass Index; D003199:Computer Systems; D003200:Computer User Training / Q000379:methods*; D003430:Cross-Sectional Studies; D004522:Educational Status; D015444:Exercise; D005260:Female; D006801:Humans; D020407:Internet; D007899:Leisure Activities; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D009765:Obesity / Q000453:epidemiology*; D050177:Overweight / Q000453:epidemiology*; D012146:Rest / Q000502:physiology; D011795:Surveys and Questionnaires; D014505:Urban Population