I have watched runners pass in front of my house and being a retired physical education professor in kinesiology, I tend to look for common posture problems that many of the runners display. There are two common errors in running form that stand out the most frequently.
One is the tendency to lean forward. Going back to Coach Bill Bowerman from the University of Oregon, who wrote about keeping an erect posture when running for more speed, this includes sprinters as well as long distance runners. Some runners think that if they want to run faster, they have to lean forward. Sprinters in the blocks lean forward for a few strides but after those few strides they assume an erect posture.
Two problems occur when a runner leans forward. One is the lead leg and knee will not come up as high because of the pelvic tilt facing downward. The second problem is the foot strike will often be in front of the body acting as a brake to forward movement. The foot should be coming backwards when it makes contact with the ground. When the weight of the body is over the foot it should be directly underneath the body for maximum efficiency. The faster you run the higher the knee lift tends to be and the bend at the knee is closer to maximum. This allows for a faster movement forward of the leg since the length is lessened. With the runner leaning forward this higher knee lift is hindered slightly and the possibility of the foot being in front of the weight of the body acting as a slight braking action occurs.
The second common problem is watching runners with an anterior (forward) pelvic tilt. You recognize this problem from the lower back curving forward – commonly called a ‘sway back’. There are a multitude of muscle problems that occur with ‘sway back.’ When the pelvic girdle tilts forward the abdominal muscles that are attached to the front part of the bone are put on a slight stretch. The hamstring muscles in the back of the leg that are attached to the bottom of the pelvic bone area are also put on a slight stretch. The low back muscles that are attached to the upper part of the pelvic bone are shortened.
My experience with a pelvic tilt occurred when I started training for marathons and ran longer distances. The internal organs hit the lower abdominal muscle attachment and began to tear it. It became painful to run because of the pain in my lower abdominal. I leveled my pelvic girdle out and that pounding was now in the pelvic bone area.
Watch for sprinters in a race suddenly grabbing the back of their leg from a cramp. If they grab in the middle area. it can come from a tight muscle. If they grab up high on the leg, the hamstring muscle was pulled because as the muscle tired and the runner tried to increase speed the hamstring strained from that pelvic tilt and pulled the muscle at the attachment.
To correct this, the abdominal muscle needs to be strengthened to help lift the pelvic girdle up to a level position. A common mistake is doing leg lifts to strengthen the lower abdominal portion. Looking at the abdominal muscle it does not attach to the leg and cannot lift them. The hip flexor (iliopsoas) muscle lifts the leg. It attaches to the lower back also and causes an increase in the sway of the back as it gets stronger and shorter. If the abdominal muscle cannot hold the weight of the legs, the pelvic girdle tilts and the abdominal muscle has a ‘stretch weakness’ and becomes weaker.
I used to do several hundred leg lifts and bent knee sit ups with my feet secured every day. I thought I had strong abdominals. A co-worker at West Point tested my abdominals. I couldn’t even pass the 40% strength level of the upper abdominal section and only 15% strength on the lower abdominal.
I needed some major correction to the exercise routine I was doing. No more leg lifts or secured feet sit ups.
