&gt; <i>However, the protective effects typically wore off after that, with recurrences rising after 12 months,</i> probably <i>because many of the people who’d been involved in the studies stopped exercising, Dr. Maher said, and their back problems returned.</i><p>Ah, speculation. In 5 years, we&#x27;ll be hearing how exercise causes chronic back pain, and the solution is to exercise for 6 months, then take 6 months off, because some other highly-decorated surgeon thinks it <i>probably</i> makes sense.