Second, tight quads might lead to hamstring muscle weakness. The opposing muscles to the quads are the hamstrings, which are positioned towards the rear of your thigh. Both conditions can have an impact on your pelvic alignment, which in turn can have an impact on your posture and pain levels. Tight quads can also result in reduced blood flow to the leg, which may cause pain during exercise or when standing up after lying down. An imbalance of strength between the quads and the hamstrings increases your risk of injury to both groups of muscles. A qualified physiotherapist can help resolve these issues and reduce your risk of further problems.