INTRODUCTION Roughly 50% of sprinters muscle injuries are to hamstrings; and 40% of soccer players injuries. Most likely to occur within the first 10 weeks of the season program. Strongest indicator of risk is imbalance hamstring (weaker ) versus quadricep ( stronger ) strength. The key factors are: 1. tight rectus femoris  (2) deactivated glutes  … Continue reading WHAT REALLY CAUSES HAMSTRING TEARS