Building an enviable physique is no easy feat.
You'll need to consistently adjust your workouts, so your body can't adjust. You'll want to maximize hypertrophy, which is essentially the process of working muscles so they come back bigger and stronger. And if you really want to stave off that dad bod and burn away that excess blubber, you'll need to keep your heart rate high and your rest periods short—and that calls for supersets.
Perform each workout (Day I, II, and III) once per week, resting at least a day between each session. Each workout will require about an hour.
Perform the exercises marked with letters in sequence. Rest as needed in between, unless directed otherwise, and repeat for all prescribed sets. Perform remaining exercises as straight sets. For the circuit on Day III (exercises 5a to 5d), use one barbell with the same amount of weight.
Choose a light load—the point here is conditioning, not strength building, so keep tight form and move fast.