In many low-income neighborhoods, obesity and diabetes are huge problems. Fear of crime and traffic keep many residents from exercising outdoors and indoor gyms are often too few and too expensive. Healthworks, a nonprofit fitness center in Boston, Massachusetts is working to change that. With membership fees based on income and no more than $30 a month, low-income communities now have a safe space to work up a sweat, shed pounds, and stay healthy. Bill Walczak, who helped make the gym possible, hopes to expand the community's access to gyms and health centers. "We're just at the tip of the iceberg," he says.