Newswise — Practices for football, cross country and other high school sports are starting up this month, and many athletes will do two-a-day workouts in the August heat.Last year, four high school football players died of heat stroke, according to the Annual Survey of Football Injury Research.High school fall sports include boys football, soccer and cross country and girls tennis, volleyball and cross country. While some teams schedule practices in early morning or early evening, other teams with limited field space must practice in the mid-day sun."Players and coaches should take common-sense precautions to prevent heat exhaustion and heat stroke," said Loyola University Health System athletic trainer Jennifer Janczak. "Players also should expect to be sore after the first days of tryouts. But soreness is not necessarily injury."Janczak is a sports medicine outreach coordinator in Ambulatory Orthopaedic Surgery and Rehabilitation. She is an athletic trainer for Trinity High School in River Forest, Ill. and Lewis University in Romeoville, Ill. She offers these safety tips:Preventing heat exhaustion and heat stroke-- Drink water before practice and during water breaks, even if you're not thirsty. Bring a water bottle.-- It may seem gross, but check your urine. If it's dark, you're not getting enough water.-- Don't drink beverages with caffeine, including tea, coffee and soda.-- If you experience dizziness, nausea, trouble concentrating, headache or heavy sweating, you may be suffering heat exhaustion. Alert your coach or athletic trainer. Rest in an air-conditioned room, or if that's not possible, get in the shade.-- Untreated heat exhaustion can develop into life-threatening heat stroke that requires immediate medical attention. Symptoms include confusion, loss of consciousness, frequent vomiting and shortness of breath and skin that feels hot but not sweaty.Injury vs. sorenessSoreness is normal when starting a new season, new drill or new lifting routine. The aching, weakness and decreased motion you feel the next day or two result from challenging muscles. Warming up and stretching can help. Continuing with the program also can ease the discomfort.Potential signs of injury include pain in a joint or muscle that follows a twist or hit and a sharp pain and/or swelling in a specific area. Tell your athletic trainer. If you try to handle it yourself, you could wind up losing more time.And make sure your equipment fits. "Equipment that is too big or too small is an injury waiting to happen," Janczak said.