In the great song by Kenny Rogers, “you have to know when to hold them, you have to know when to fold them.” By changing a couple of words the same concept applies to skill technique.
This means you have to know if you should change running technique and you should know when to change running technique. We can even add that you should know how to change running technique if and when called for. Very often changes in technique are made that are uncalled for that bring about even worse performances.
It appears that poorer performances are quite commonplace from improper corrections. For example, a popular case in point is when the across-the-body arm swing of world-class marathoner Bill Rogers was changed to be biomechanically “correct”. The changes resulted in poorer performances.
The changes in this case were related to directing the pathway of the arms rather than the causative factor for the arms coming across the body. From my experiences in analyzing hundreds of runners, it is extremely rare to find a runner who brings his arms across the body. This is based on looking at the arm motion in relation to the position of the shoulders.
Visually seeing the arms cross the midline of the body may appear to be controversial because if you look at the runner from the front, you can definitely see the arms crossing the chest. However, the reason for this is not the pathway that the arms take, but the excessive rotation of the shoulders.
You can prove this very easily for yourself. Hold your arms, bent at 90° in the elbow, alongside your body. Then rotate the shoulders to the right or left and you’ll see that the arms “cross” the body. The more you rotate the shoulders the more the arms cross the midline of the body.
But the arms are still in the same relationship to the trunk! In other words, the crossing of the arms is due to the shoulder rotation, not the pathway taken by the arms themselves. Thus, if you try to correct the arm pattern you will invariably be changing something that was not incorrect. In this case you are not addressing the main causative factor.
Because of the concentration needed to have the arms go forward and backward while the shoulders rotate left and right, it is understandable that his performance decreased. If you try to do this even without running, you’ll see how difficult it is. Therefore it is not surprising that this change did not lead to running improvement.
In this case there was incorrect identification of the problem followed by erroneous corrections. This in turn resulted in poorer performances. But yet, the solution was really quite simple. If the shoulder rotation – and not the arm action – was addressed and corrected it would have resulted in better performances.
For more information on the arm swing and how it can be improved, see Explosive Running