It’s true, even in Texas, where researchers at the University of Texas Southwestern Medical Center in Dallas have found that among nearly 20,000 adults in their mid to late 40s, the most fit had a 37 percent lower risk of having a stroke after 65, compared with the least fit. HealthDay reports that the researchers analyzed 1999-2009 data from a study conducted by the Cooper Institute in Dallas, and used treadmill tests to measure heart and lung exercise capacity when participants were 45 to 50. What to do?  The researchers recommend an exercise routine that includes aerobic exercise (such as jogging, swimming, walking or biking), plus strengthening exercise (such as free weights or strength-training machines).