Can Physical Activity be Designed Back into American Lives? Mark Fenton Pedestrian and Bicycle Information Center Univ. of North Carolina

Point 1: There’s an epidemic of physical inactivity in America. Point 2. Just trying to change individual behavior has NOT solved the problem. Point 3. We know how to build more pedestrian and bike-friendly communities. Point 4. We must do it all—build active settings, and work to change behavior!

Point 1: It’s not just an obesity epidemic. It’s an epidemic of physical inactivity.

Surgeon General’s 1996 Activity Recommendation 30 minutes of activity. Most days of the week. Can be broken up. Reduced risk for CVD, diabetes, osteoporosis, obesity, clinical depression, some forms of cancer.

The Obesity Epidemic in the US Flegal et. al. (JAMA 288, 14; Oct. 2002)

Physical Activity in the US (MMWR 50 (09); 166-9; Mar. 9, 2001)

Physical activity recommendation for children: (1994 consensus conf.) Physically active everyday as part of lifestyle (30-60 minutes). 20 minutes of vigorous activity, at least 3 days/week.

US Youth Overweight Rates JAMA 288 (14); Oct 9, 2002.

US Youth Physical Activity Rates (CDC: Youth Risk Behavior Survey)

Self-help vs. Commercial Weight Loss Programs (Heshka et.al., JAMA 289, 14; April 9, 2003)

First Law of Thermodynamics: E IN – E OUT = E STORED Can’t just focus on nutrition (E IN ). Have to increase physical activity (E OUT ) to attain a balance!

Point 2. It’s not just about individual behavior change. Interventions to change behavior last for several months, then the effects tend to wear off.

Exercise Participation Effect of Short Bouts, Home Treadmills (Jakicic et.al., JAMA 282, 16)

Individual Behavior Change Aids See Dunn & Blair, “Active Living Everyday” Social support Scheduling Goals, rewards Measurement Recording (log) Substitution Mapping

Energy Expenditure Lifestyle vs. Structured Activity (Dunn et.al., JAMA 281, 4)

Point 3. The Goal: Reintegrate physical activity into the lives of all Americans.

Transportation: We’ll walk and bike, if we have places to do it.

But we still build mostly this:

US Walking Trips National Personal Transportation Survey, USDOT

US Auto Trips National Personal Transportation Survey, USDOT

The ideal “trip” decision hierarchy for a more physically active America * : Walk Bike Transit Drive *Nearly 25% of trips are less than or equal to one mile. (1995, NPTS)

Do incidental walking trips matter? Imagine: Eliminate 20 minutes of walking, 5 days a week (2 kcal/min vs. 4 kcal/min). Net loss of 40 kcal/day. 200 kcal/week = 10,400 kcal/year ~ 3 lbs./year (30 lbs./decade!)

Simplified elements of pedestrian and bicycle friendly settings: Network. Land use. Safety. Site Design. Commitment.

Walkable, bikable places have: Continuous networks of footpaths, multi-use trails, and sidewalks.

Walkable, bikable places have: Compact, dense, and diverse development and zoning.

Walkable, bikable places are: Safe for all cyclists and pedestrians (not just skilled ones).

Walkable, bikable places are: Aesthetically pleasing and functional for pedestrians and bicylists.

Walkable, bikable places have: A civic commitment to walking and cycling, from top to bottom.

Point 4. A better way for public health: A socio- ecological approach to increasing physical activity.

Social Ecology Model Determinants of behavior change Sallis, Owen, “Physical Activity and Behavioral Medicine.” Individual (readiness, efficacy) Interpersonal (family, friends) Institutional (school, work, HMO) Community (networks, local gov’t) Public Policy (transport, land use)

Social Ecology Model of success: tobacco Individual – education, medication Interpersonal – 2 nd hand smoke, kids Institutional – work place bans Community – smoke free policies Public Policy – taxes, enforcement, advertising bans, SG’s warning label.

The Future of Physical Activity in the US? (Nothing more than hopeful conjecture.)