So the number one reason people end in care facilities is because they can't get off the toilet, or up from being on the floor.

The stronger/healthier you are now (and maintain it), the less likely you will break a bone as you age.

We store calcium in our bones until about age 30, when it starts to slow. I think by age 50,its really slowed to a crawl. As we age, we become less and less efficient at storing calcium due to hormonal changes, which leads to weaker bones - why older people break bones more easily.

So build your muscles before age 40, as the strength of muscles impacts bone density (since they attach to bones, and the stress they induce at origin/insertion influences bone density). Trying to build muscle as you age gets more risky for because of this stress.

Also improve your cardiovascular capacity now. Ira easier to do than when older, has long term health influence, and isn't the risk of doing it when you're older.

Everything gets harder as we age. The more you improve conditioning now, the better tomorrow will be.