Well not everyone is going to agree on the squat that's for sure....
The thing about squatting is, there are a lot of different ways to do it, and you don't have to be an Olympic-style lifter to get the benefits. There's no doubt that squatting is good for you. There's published research linking human longevity to the practice of squatting for everyday activities. And one of the first things a good trainer will do with a new subject is a squat assessment.
Like someone already said, squatting uses a lot of muscles at once and you can vary that by technique. And it uses the muscles that are most important to human locomotion, and staying upright as one gets older.
I see the trainers at my gym (who all have at least a BS in kinesiology) working with older people every day, and they all work some type of squat with lighter weights into the routine. Mostly a goblet squat with a light kettle bell.
A squat works the strongest muscles in the body (legs) directly through the weakest/most prone to injury part of the body (the lower back). Obviously, fairly light squats aren't a big deal, but why risk it, especially as you age, when you can work those muscle groups in ways that bypass the lower back, and still do all manner of lower back exercises that are back safe?
My best friend, who is one of the smartest and strongest lifters I know (had a minor in kinesiology, and had a 620lb squat in college), has raised his four boys lifting. The only lift he would NOT let them do is the squat. He thinks it's one of the worst possible things you can do to your body. There are simply much more spine friendly ways to achieve the same results. At least that's the way I see it. Didn't intend to rile you up gentlemen.
Over and out, I gotta go run stairs...
“Perfection is Achieved Not When There Is Nothing More to Add, But When There Is Nothing Left to Take Away” Antoine de Saint-Exupery
