65-year-old Rick Brown of Marietta was one of three runners who collapsed and died during a half marathon in Detroit over the weekend.
It's a tragedy that has workout safety on the minds of many.
Whether you're a trained marathon runner or a workout beginner, trainers say there are some basic guidelines everyone should follow.
"If there's any upper body discomfort of if they can't hold a normal conversation comfortably they need to back it down, watch their heart rate," Krystal Wittekind, a personal trainer at Anytime Fitness in Marietta, said.
Trainers also say you should check with a doctor before starting any exercise program.
It's also important to stay hydrated and be even more cautious when exercising outside on hot days.