Rod Havriluk, Research Quarterly for Exercise and Sport, 2012, 83(2), 359-362.
A recent article by Schnitzler, Seifert, and Chollet (2011) on arm coordination in swimming draws a conclusion that seems inconsistent with their findings. They have used an index of coordination (IdC) to quantify arm synchronization, which has become a very practical standard to measure gaps (negative IdC) and overlaps (positive IdC) in arm propulsion. Their previous work supported an increase in IdC with swimming velocity and performance level, as consistent with mechanics and physiology. Their recent study showed a lower IdC for expert swimmers than for recreational swimmers and concluded “catch-up coordination can be an efficient coordination mode.” In the hopes of preventing coaches and swimmers from using this finding to justify “catch-up stroke,” other explanations are suggested.