Doing an hour of cardio every day might be too much. (I'm talking about something which is higher intensity than fast walking... That would be great.) Half an hour three times a week would be fine. The issue is with adherence, and also the body's negative response to this much exercise. In many people (including me for sure) it triggers an adaptation that makes them try to conserve calories by making them feel sluggish and lethargic later on.
Weight training has similar effects. The body can be in an anabolic mode with a caloric surplus, and in that case, yes it's good to work hard in the gym. (Most people shouldn't go to failure very often if ever though.) But when you are in a catabolic mode, working out very hard with weights is going to lead to adherence issues again, e.g. dreading the workouts. You don't really need to do all that much to maintain muscle mass, as opposed to building it when you are approaching your genetic limit. Three times in the gym per week at 30-45 minutes per session would be just fine in my opinion.
In summary, picking something you can adhere to is far more important than trying to optimize the equations in a way that someone with infinite willpower might manage.
Don't buy into the "genetic limit" line of thinking. The limit on the amount of muscle mass you can pack onto your body is much higher than most people have the will to achieve.
My issue is not length, but intensity. I understood "not doing too much in the gym" to mean "don't work too hard." If instead you meant use your time in the gym wisely, then that I agree with. But if you want to see continued improvement, then you need to increase the intensity over time. Despite being in the gym the same amount as some people, I'm in better shape because I work harder.
I agree with your summary, but I would stress "work hard." I've found that working hard and continually trying to improve actually makes workouts more fun.
Everyone has a genetic limit. I'm not going to bench press 700 pounds. Therefore the set of all things I could do (naturally) in my lifetime to raise it has a least upper bound. QED:)
There's a time for intensity. As someone starts to get diminishing returns, the needs increase for higher intensity, probably higher volume, and higher complexity e.g. periodization or something even more complicated than that. The time for intensity is not when you are just starting weight training, in which case anything will work (but someone should do exercises properly of course.) The time for intensity is doubly not when your primarily goal is to lose weight, in which case the body isn't going to have its full resources to repair itself.
Quoting myself, adding emphasis, "The limit on the amount of muscle mass you can pack onto your body is much higher than most people have the will to achieve." A 700 pound bench press is actually humanly possible, as the record for a raw, drug tested bench is 711 pounds. If you said 2000 pounds, then I'd agree with you; I think that's beyond human capacity. But 700 pounds is within human capacity, and your limit is your will.
Increasing the speed throughout the extent of a treadmill run takes my mind off the pain, cuz I'm trying to appreciate the slower speeds before I have to go faster:)
Weight training has similar effects. The body can be in an anabolic mode with a caloric surplus, and in that case, yes it's good to work hard in the gym. (Most people shouldn't go to failure very often if ever though.) But when you are in a catabolic mode, working out very hard with weights is going to lead to adherence issues again, e.g. dreading the workouts. You don't really need to do all that much to maintain muscle mass, as opposed to building it when you are approaching your genetic limit. Three times in the gym per week at 30-45 minutes per session would be just fine in my opinion.
In summary, picking something you can adhere to is far more important than trying to optimize the equations in a way that someone with infinite willpower might manage.