Can I propose a corollary to Betteridge&#x27;s Law wherein &quot;A or B?&quot; headlines can be (almost invariably) answered with &quot;It depends.&quot;<p>(You can do workouts on a treadmill that are difficult outdoors and vice versa.  Same with bike trainers.  Same with those &quot;infinite&quot; swimming pools.  You should probably do a bit of both.  It&#x27;s a bloody daft question.)