I’m going to disagree with the book. I trained for the Olympic decathlon for a decade and still workout 1 1/2 to 2 hours daily. Granted every person is different but just about all studies I’ve read say it’s vigorous daily exercise which increases life expectancy and keeps you healthiest.
My wife & I try to do a 6-10 mile walk/hike each week. Distance depends on how demanding the trail is. I like jogging but I see no sign jogging 3 miles gives the benefit hiking 10 does.
I’m a firm believer in weight lifting of some sort. I prefer bodyweight exercises when possible, done to the point of “serious effort”. Trying to exercise to “failure” in my old age causes injuries. Nearing failure, or serious effort that leaves me worn out, shows strength improvement without the injuries. As I get older (60s), injuries take forever to heal. Isometric exercises are good ways to hit “failure” without the strain on my joints or danger of losing control.
But yes, I think best results mean “vigorous exercise”. 30 minutes a day beats the snot out of zero - something I remind myself when I have trouble getting started - but I think it’s better to do more at least 1-2 times a week.