The new study included nearly 107,000 runners who were grouped according to the distance they run each day: less than 1.2 miles (under 2 kilometers [km]); 1.2 to 2.4 miles (2 to 4 km); 2.4 to 3.7 miles (4 to 6 km); 3.7 to nearly 5 miles (6 to 8 km); and about 5 miles (8 km) or more.
The researchers found that body mass index and waist circumference increased significantly among the least active runners when they ate more meat and less fruit. But the effects of this diet change were reduced by 50 percent or more in the most active runners. The effects in runners who covered more than 1.2 miles a day were also reduced, but not to the same extent as the highest-mileage runners.
The study is published in the November issue of the journal Medicine & Science in Sports & Exercise.
"Generally, body mass index and waist circumference increase as a person eats more meat and less fruit," study author Paul Williams, a researcher at the U.S. government's Lawrence Berkeley National Laboratory, said in news release from the American College of Sports Medicine. More>