Instant recess: Periodic exercise breaks

By JANE E. BRODY NEW YORK TIMES NEWS SERVICE We all know by now that we should be getting 30 minutes a day of moderate to vigorous physical activity on most days. Yet for all the proselytizing, wheedling, and cajoling, only about 5 percent of the population has bought into the program. “Being sedentary is the norm in America,” writes Dr. Toni Yancey, a professor of health services at the …