hi doc. i am doing athletics i did do marathons and road running but let it go because I experience lower back pain and my right leg is weak seems that i carry it, it get lame extreme weak,I then run limpy,I then left the road running and doing track as i was also a good sprinter.I am 53 and can run a 100m in 13,50 but i know i can do sub 13 IN the 200m race,the last part 50m i must carry my leg as it get weak, i also have a looming inner thigh muscle strain right leg and left looming hamstring