People who engage in no leisure-time physical activity can produce important improvements in health with small increases in activity, U.S. health officials say.A report, published in the Centers for Disease Control and Prevention Morbidity and Mortality Weekly Report, published Thursday, said some subgroups, such as adults with arthritis, have exceptionally high rates of no leisure-time physical activity.\"In 2009, adults with arthritis had a 53 percent higher prevalence of no leisure-time physical activity compared with adults without arthritis,\" the report said. \"Rates of no leisure-time physical activity among adults with arthritis were significantly higher in every state and the District of Columbia compared with adults without arthritis. In addition, adults with arthritis accounted for 25 percent to 47 percent of all adults reporting no leisure-time physical activity.\"To reduce the prevalence of no leisure-time physical activity among all adults, physical activity promotion initiatives should target adults with the use of evidence-based, arthritis-tailored interventions, heath officials said.