Buddabing: actually, there is. Except for yoga, which descends from elements of the royal court (Indian wrestlers and Tibetan monks have been doing hindu push-ups and hindu squats and bridging, amongst other things, for millenia), there are no other exercises as comprehensive and effective as the Royal Court.
Why? Two things: multi-tissue activation (connective as well as muscular), and dynamic stretching. Even with low-impact, low weight weight-training, the muscles are still largely the tissues addressed, the motion involved is linear ( = not very functional), and there is required stretching afterwards. Equally, cardio isn't very functional cos it doesn't address strength, degrades the connective tissues, and requires a lot of time.
Spending 15 minutes doing, say, two sets of the royal court, without doing it quickly, will do all of those things: strength (and muscle, if vanity is your thing), endurance and stamina, and flexibility. However, as I mentioned above, you could do one exercise - that being bear crawls - for a few to several minutes, at a medium-slow pace, if you can handle it, and satisfy these criteria, anyway.
Lastly, on diet, I disagree. Partly, as my post above confirms, diet is all important. But to add to this, I give the following: the second time I was lifting, I got to a point where I had a bunch of muscle - but I also was getting a little full-looking. I hadn't been doing cardio, but was doing about an hour of lifting, three times a week. I added a half-hour of cardio. No change in weight or look after a month. What was the problem? I was eatin too much ---goshdarn--- baked goods. Oh, sure, they were whole grains an all. Don't make no difference. Then, some time later, I reduced my training. I also reduced my grain intake. I lost weight.
The other thing is that if you don't nutrify your tissues - and the most important here are your internal organs - you'll run your body down. And, like I mentioned, diet determines your mental state. Give your body what it genetically is predisposed to metabolise, and it normalises. You don't even have to make an effort at this point, cos your body is satisfied.
PS: you might be interested in what my intake is.