"When you and your family plan a picnic this summer, why not walk there instead of drive?" suggests Ash E. Hays, executive director of the President's Council on Physical Fitness and Sports. "And don't just sit right down to eat. Take a hike or play a game first."

Hays' picnicking tips will help keep you in shape. The following advice from The Children's Hospital in Boston, Mass., will help keep your picnics safe to eat.

"Summer weather provides ideal conditions for the growth of bacteria that cause food poisoning," says Roberta Henry, director of nutrition at the hospital. Bacteria are invisible organisms, or germs, that can grow in food and make the people who eat it very sick. A kind of bacteria called salmonella can grow in meat that is raw or incompletely cooked, and in eggs and shellfish. The best prevention is to cook these foods thoroughly before eating them. Hamburgers, pork chops and ribs should be cooked until all the pink is gone. Poultry should be cooked until there's no red at the joints.

Another kind of bacteria called staph can grow in dairy products and eggs. "To avoid staph, always wash your hands before handling food," Henry says. "Keep food refrigerated or in a cooler until it is eaten. Do not pack dairy products or egg-based foods in picnics unless they are in a cooler."

If food poisoning is suspected, contact a doctor or your local poison control center. The symptoms of food poisoning resemble intestinal flu, including vomiting, cramps, diarrhea, and fever.

The U.S. Department of Agriculture publishes a free booklet called "Safe Food to Go" with advice on storing, cooking and packing food to eat away from home. For a free copy write to: F. James, Dept. 597P, Consumer Information Center, Pueblo, Colo. 81009.