"Does Core Strength Training Influence Running Kinetics, LE Stability, and 5000M Performance in Runners?"- JSCR Jan. 2009 p. 133
Jack Blatherwick at GAIN 09 explained to us why you shouldn't just read the abstracts.
In this study, 28 subjects in their late 20's to late 30's were quantified for core stability weakness by way of the Sahrmann Core Stability Test. 12 received core stability training by way of 5 physioball exercises. 8 "were instructed to maintain their training routines". 8 dropped out, not sure why. After 6 weeks, the core training group showed faster times, even though there were no improvements in ground reaction force.
The problem is there was no "plecebo" generalized strength training group. After all, they were not college aged athletes, and may very well not been inolved in any strength & conditioning program. Therefore, any intervention would have seen an improvement.
The other problem is the assessment tool- Sahrmann's core stability test. It is a series of leg lifts done in the supine hook lying position. Does it fit here?
So, we'll never know if the author's protocol was effective or not.