As Rich noted, the body has a harder time digesting food when running ( blood flow is shunted away from the digestive system to exercising muscle ).
(Rich; noted; ) (the body; has; a harder time digesting food) (blood flow; is shunted; away from the digestive system; to exercising muscle)
Rich the body blood flow
noted has is shunted
a harder time digesting food
away from the digestive system to exercising muscle