Yard Work Aches   Just as playing football or golf can injure your body, the twisting, turning, bending, and reaching of mowing and raking can also cause injury if your body is not prepared. So before you rev up the lawnmower or reach for the rake this fall, consider these possible consequences: upper or lower-back strain, neck strain and pain in the shoulders. So, prepare yourself as any athlete would before a game.     What You Can Do... • Perform stretching exercises, without bouncing, for a total of 10 to 15 minutes spread over the course of your work. Do knee-to-chest pulls, trunk rotations, and side bends with hands above your head and fingers locked. Take a short walk to stimulate circulation. When finished with the yard work, repeat the stretching exercises. • Stand as straight as possible, and keep your head up as you rake or mow. • When it's still warm outside, avoid the heat. If you're a morning person, get the work done before 10 a.m. Otherwise, do your chores after 6 p.m. • When raking, use a "scissors" stance: right foot forward and left foot back for a few minutes, then reverse, putting your left foot forward and right foot back. • Bend at the knees, not the waist, as you pick up piles of leaves or grass from the grass catcher. Make the piles small to decrease the possibility of back strain. • When mowing, use your whole bodyweight to push the mower, rather than just your arms and back. • If your mower has a pull cord, don't twist at the waist or yank the cord. Instead, bend at the knees and pull in one smooth motion. • Drink lots of water, wear a hat, shoes and protective glasses. And, to avoid blisters, try wearing gloves. If your equipment is loud, wear hearing protection, and if you have asthma or allergies, wear a mask. Try ergonomic tools. They're engineered to protect you when used properly. • If you do feel soreness or stiffness in your back, use ice to soothe the discomfort. If there's no improvement in two or three days, see your chiropractor.