If you were only ever allowed to do one exercise, I would say the squats is the best.
It hits the big muscles. Forces you to learn balance through the range of motion. And improves flexibility.
The hormone release from training big muscles under heavy weight will echo throughout the body and help stimulate growth everywhere.
Deadlift is more fun, hits the big muscles, and you can go even heavier. But I don’t see the same benefits when I focus on a heavy deadlift cycle as compared to a heavy squat cycle.
The CNR fatigue really helps with getting to sleep and I feel better the following week(s).
I feel great on a DL cycle and my proportions make me relatively much better at deads than squats so I tend to do them more. But I also recognize that for general health and fitness squats are probably better if you were forced to choose.
Personally I've found overhead pressing to be prone to to pulling my back, and only do it with a belt now.
I don't tell anyone to deadlift unless I'm there coaching them. Even then, I'm not good enough. You should get a qualified trainer if you want to deadlift, and you should make damn sure your doing everything else right first, sleeping, stretching, eating right, etc.
The % of people who are gonna benefit from walking up to a bar and doing a deadlift right now in the West is probably something like 10%.
You think it's not a big deal until you start meeting people who seriously injured themselves..some of them have been working out for years, some just getting started.
Since this is in the context of benefits for older people, Stuart McGill, a back expert who has helped lots of power-lifters recover from major injuries, recommends against going for higher and higher PRs as you get older:
https://www.youtube.com/watch?v=tM599A6wUAw&pp=ygUXaXMgZGVhZ...
(What's not clear to me after watching the video was if just doing moderately-heavy sets of 12 would introduce the same kind of risk he's talking about.)
ETA: The kind of injury he's talking about is decades-long cumulative bone and joint injury that only starts to be noticeable once you're 70. (Unless you're a wordl-class competitive athlete, in which case you notice a lot earlier.). Early in the video he talks about 50-year-old powerlifters coming to him, asking how they can continue to do PRs into their 60's. And he says, basically, do you want to do PRs through your 60's, or do you want to be able to get down on the ground and play with your grandkids when you're 85? Because I can help you do one or the other, but I can't help you do both.
One of the points he makes frequently in his videos is that while bones can get stronger, similar to muscles, the rest time they need to actually recover from being stressed is a lot longer; something like 7 days. And so if you're deadlifting PRs for years and years, with only 3-4 days between maxed-out sets, you're going to be accumulating micro-fractures in your vertebrae, which will eventually catch up with you.
Anyway, def worth the watch.
Drs. Baraki and Feigenbaum's (from Barbell Medicine) response: https://player.fm/series/barbell-medicine-podcast/episode-29...
Jonathon Sullivan's response (author of The Barbell Prescription): https://www.youtube.com/watch?v=O491cW89Ky8
The first link seems to be in response to a podcast by Andrew Huberman (sp?) about back pain, which also contains some comments about McGill in general; but nothing directly about what he says in the video I posted. People might find it interesting in its own right but not as directly relevant to the question of deadlifts in older people.
If anyone is interested in learning about weight lifting, Starting Strength (by Mark Rippetoe) is a GREAT book to start with!
It's possible to move from an easier form (simple squat) to a harder one by progressively shifting weight on one leg at a time.
Usually, though, pushing strength is enough for most people for their legs, so if you mean in terms of hard, difficult movements, then working your way up to pistol squats is a good goal for most people.
The only exception is low-bar/leg disability, then I think it might be better to keep it bodyweight and machine oriented (such as leg press).
Starting slow and doing good form squats and slow burpees could improve your knee health to the point where you can do regular-tempo burpees. However, don't get medical advice from internet forums.
Deads hit mostly glutes and hams, almost no quads, but a bit more back involvement
I recommend doing both, personally
If you want bodyweight only then probably pistol squats but it's difficult to work the legs that much with just bodyweight because they already carry your body weight every day
It does require a bicycle (and shoes/straps), but a bike isn't usually considered gym equipment, and it's heavily involved with your body weight.
If you have a good 40m to run, then I would also do interval sprints.