Pose running and ChiRunning have many similarities in how they approach the mechanics of running. Both teach the mid-foot strike, a forward lean and proper alignment, and they both coach practitioners to use the pull of gravity to propel them forward rather than making their legs do all of the explosive, tiring work.
But there are also some subtle differences that could make a significant impact on whether or not one technique is right for a certain runner. Pose running puts more demand on the legs, using muscle control to maintain proper positioning. ChiRunning teaches that the leg below the knee should be relaxed, taxing the muscle very little. The primary focus of ChiRunners is core strength and the belief that energy can be redirected from the trunk to the extremities. Another key difference is that pose running uses a short stride while ChiRunning extends the stride, again to alleviate the effort on leg muscles.
Finally, probably the most distinguishing characteristic between these two approaches is that pose running is primarily focused on the physiological elements of running. ChiRunning on the other hand, is steeped in Eastern philosophies that, while may be perfectly valid, Western runners may have trouble applying.
Like most fitness topics, there are volumes of research on proper running form and experts are more than happy to weigh in on which is the best. These are just two variations on improving running form, and each one is bolstered by anecdotal and scientific findings to support its claim. But each runner is different, and in the next section we'll discuss the benefits, dangers and complexities of adopting a new running style.