I was talking with a few personal trainers and athletic trainers during the past few weeks and the discussion was about the different types of injuries that are caused by participating in sports and activities. It seems each sport has one or two types of injuries that occur more frequently than the usual sprained ankle injury. And some injuries do not happen in sports. I have had flute players and accountants with injuries that required exercises to correct the problem. It just seems that if a person participates in an activity that is repetitive an injury may occur over time. It may start out at a young age with the so-called teenage slouch that will lead to problems as they reach adulthood.
For runners there are several types of injuries that can occur from muscle imbalance in the core area of the body. The main recognition of this imbalance is a sway back. The core area is the abdominal muscle, the low back muscles, the hip flexors and the hamstrings. The initial cause is a forward tilt of the pelvic girdle. The usual imbalance is the hip flexor muscles (ilio-psoas) is strong and causes the pelvis to tilt forward. This forward tilt puts a stretch on the abdominal muscles. The sway back caused by the pelvic tilt in turn causes the low back muscles (sacrospinalis) to shorten. With the pelvis tilting forward the posterior side of the pelvis is slightly higher. This extra height of the pelvis causes the hamstring muscles that attach to the underside of the pelvis to be put on a stretch.
The resulting hip flexion strength and shortening combined with the lower abdominal muscle being stretched can cause an injury. I didn’t notice this imbalance until I started to train for marathons and started to put in long runs. With the pelvic tilt the internal organs were pushed against the lower abdominal muscle attachment on the pelvis. It created a painful lower abdominal muscle stretch and weakness. I had to change my running posture from a sway back to a level pelvic girdle.
