Research suggests most North American college and professional hockey players don't specialize as youngsters.
Trainers have used Lasix for decades to reduce bleeding and improve performance in North American racehorses.
Research suggests that developing strength or aerobic fitness can improve long-term health. But is another method even better?
The goals of a major push for football helmet safety should bring improvements, but the overall results remain unpredictable.
Ongoing studies try to quantify the risks and benefits of contact sports.