Exercise for chronic back pain: The beige trouser effect? Most commonly used exercise therapies for back pain are aimed at having an effect on some mechanical or tissue based aspect of spinal function. From range of motion exercises to muscle balance, endurance or strengthening exercises the (not unreasonable) rationale is that back pain is associated with abnormal spinal function -- address that with exercise and back pain should improve. The problem is that, whichever way you slice the data, the effects of exercise are small to moderate at best (kind of the therapeutic equivalent of beige slacks, better than nothing but generally underwhelming).  It doesn't seem to matter what type of exercise you do, comparative trials of different types rarely demonstrate a difference and systematic reviews have not clearly demonstrated a type of exercise that is superior. Many argue that the problem is with the data not the treatments; the lack of targeting treatments to the group of patients for whom it is appropriate means that the true effect is washed out by all those people in the trial for whom the treatment was inappropriate or ineffective. But you all know this already and I am repeating myself. A new review out of Switzerland, just published in the European Spine Journal has taken the issues of exercise therapy for CLBP and subgroups and looked at the data in a different way. If there are specific subgroups of patients for whom exercise regimes work the way that they were designed to,