The purpose of this investigation is to conduct an 8-week pilot study to examine the effects
of two different leisure-time activity prescriptions on dietary intake, leisure-time
activities, and weight loss in 26 adults receiving a standard 8-week behavioral weight loss
In adult observational studies, TV viewing has been positively related to overweight and
obesity. It is theorized that TV watching influences eating and activity behaviors, such
that with greater TV watching less physical activity and greater consumption of energy
occurs, producing a positive energy balance state. While no experimental research has been
conducted with adults examining the influence of reducing TV watching on weight status,
experimental research conducted with children does indicate that lower levels of TV watching
can produce reduced energy intake and greater levels of physical activity. Most
importantly, family-based, behavioral childhood obesity interventions that have targeted
reducing sedentary behaviors (which includes TV watching) have found that as compared to
targeting increasing physical activity during treatment, similar increases in activity and
fitness occur, but that greater weight loss and greater increases in liking for physical
activity occur when sedentary behaviors, as compared to physical activity, are targeted in
family-based behavioral childhood weight control programs.
Thus, this investigation will involve an 8-week pilot study to examine the effects of two
different leisure-time activity prescriptions. All participants in the investigation will
receive a standard 8-week behavioral obesity intervention. The intervention will include a
reduced caloric prescription (1200-1500 kcal/day) and fat gram prescription (30% or less
kcals from fat). One condition will receive an activity goal (200 minutes/week of
moderate-intense physical activity [Physical Activity]), while the other condition will
receive a TV watching goal (10 hours/week [ TV Watching]). Participants will be assessed at
0 and 9 weeks (pre- and post-intervention) on measures of dietary intake, physical activity,
TV watching, liking of physical activity and TV watching, and weight.
- Body mass index (BMI) between 25 and 40 kg/m2
- Watch > 16 hours per week of TV
- Engage in < 100 minutes of moderate-intense physical activity per week
- Participants reporting a heart condition, chest pain during periods of activity or
rest, or loss of consciousness on the Physical Activity Readiness Questionnaire
(PAR-Q). Individuals self-reporting joint problems, prescription medication usage
related to heart conditions, or other medical conditions that could limit exercise
will be required to obtain written physician consent to participate.
- Reporting they are unable to walk for 2 blocks (1/4 mile) without stopping.
- Reporting no TVs in the home or 5 or more TVs in the home viewed by the participant
(TVs in participant's children's bedrooms will not be counted).
- Reporting major psychiatric diseases or organic brain syndromes via a phone screen.
- Participating in a weight loss program and/or taking weight loss medication or that
have lost > 5% of body weight during the past 6 months.
- Participating in a program to increase physical activity and/or decrease TV watching
- Intending to move to another city within the time frame of the investigation.
- Being pregnant, lactating, less than 6 months post-partum, or planning to become
pregnant during the time frame of the investigation.
- Having had gastric surgery for weight loss.
- Being unwilling to attend weekly sessions.