Anonymous wrote:15 minutes of cardio and 15 minutes of weightlifting. That’s sort of pointless.
You don't want to exercise on a full stomach.
Exercise should be occasionally intense. You can do lighter recovery workouts. But you should not do heavy squats two days in a row. So alternating days of cardio with weightlifting is fine. It gives you twice as much time per activity. Roger Bannister often ran 10 one-minute laps with 2-minutes rests. Do you really run fast for longer than 30 minutes?
Crossfit classes are one hour long, including warm-up, skill practice, and stretching/mobility cool down. That actual workout is less than 20 minutes.
The Tabata workout is only 4-minutes long, with one-third of it spent resting. It is intense!
The Starting Strength workout is 3 work sets or 3 exercises of 5 reps (plus warm ups), 3 times per week. Only one workout per week is heavy. IIRC, middle-aged folks can do 2 works sets twice week.
It wastes time to spend as much time driving as exercising. So I would try to do some workouts at home. You could run or bike outside or inside. I use my Concept 2 rower with push-ups or dumbbell presses. Get a stationary bike, a couple kettlebells, a jump rope, or a pull up bar.