This is not unique to Catholicism. Stop and consider for a moment the activities that go on every day in the typical gym. People labor away on stationary bikes, elliptical machines, and treadmills; they sweat their way through pull-ups, push-ups, and deadlifts. In all sorts of ways, they discipline their bodies so as to overcome the natural tendency toward laziness and self-indulgence. More to it, these same people most likely deny themselves all sorts of pleasurable foods, resisting cravings.
All of this punishment is in service of a healthier body. Why can’t we apply similar techniques to produce healthier minds and spirits?
Today, discipline your body in some small way. Maybe give up snacking between meals, only drink room-temperature water, or pray an entire rosary while walking. These simple bodily disciplines will undoubtedly strengthen your soul.