Objective: To compare the frequency and duration of varying intensities of physical activity performed by adults trying to lose weight, avoid gaining weight and not actively trying to control their weight, and to compare these groups' beliefs about the physical activity they should perform.
Method: Random postal survey of 2500 Victorian adults selected from the Australian electoral roll (response rate=42%).
Measures: One-week physical activity recall (frequency and duration of walking, other moderate activity and vigorous activity), BMI (based on self-reported height and weight) and weight-control behaviour.
Results: At the time of the survey, 27% of respondents were actively trying to avoid gaining weight, 23.9% trying to lose weight and 49.1% undertaking no weight control. Respondents spent a mean time of 4.0 (±7.1) h walking, 5.5 (±7.9) h in moderate activity and 3.1(±5.9) h in vigorous activity during the week prior to the survey. Women trying to lose weight or avoid gaining weight engaged in vigorous activity more often than women not trying to control their weight. After adjusting for age, education and BMI, women trying to avoid gaining weight were 2.4 times more likely, and women trying to lose weight 2.5 times more likely, to have met current physical activity guidelines than women undertaking no weight control. On average, respondents believed they should spend 5.2 (±6.9) h walking, 6.5 (±8.2) h in moderate activity and 4.3 (±6.5) h in vigorous activity each week. Women trying to lose weight felt they should perform vigorous activity more often than other women. Weight-control behaviour was not associated with physical activity beliefs and behaviours of men.
Conclusion: Walking is a common activity among adults attempting weight control. However, many men and women do not fully recognize the value of moderate-intensity physical activity. Future efforts should be directed at promoting the role of moderate-intensity activity in weight control, particularly activity that can be performed outside of planned activity sessions.