This exercise will strengthen your hamstrings. = This exercise will strengthen your hamstring muscles.这项锻炼会使你的胭绳肌强健。Athletes cannot run very well if they hurt their hamstrings.运动员如果腿筋受伤的话，就不能跑得好。This exercise strengthens the lower back and stretches the hamstrings.这项运动使后腰部更结实，并舒展了旁腱。