Running does not necessarily in and of itself improve posture that is 
already poor and constricted. It often exaggerates problems due to the 
substitution of inappropriate muscles. The repetitive inappropriate development 
of the musculature (as in body building or weight lifting) often leads to 
diminished sensitivity. Stress occurs in the knees and lower back, encouraging 
injury.
(Liz Koch)
 
(Liz Koch)