The first truth about working out is that, in the long-term, it doesn’t matter what you do to work out. Lift weights, swim, hike around the neighborhood with your dog, cross-country ski, do squats while wearing inline skates (I’ve seen that), it just doesn’t matter. The gym-rat bench-pressing 250 pounds fully believes that is the way forward, and for him, that’s true. That day, right there, he is working out. That’s what matters. Doing something physical, pretty much every day, kicks ass on not doing something physical. If movement doesn’t happen, then atrophy is winning. Atrophy always wins eventually, but it doesn’t have to win today. Today is a good day to work out.
The second truth is that individual workouts don’t matter much, but...