When it happened to me it was like a bolt of lightning striking my lower back. In the midst of some intensive exercise I stopped, ironically, to move a small dumbbell away from my feet to avoid the possibly of tripping on it. I leant over, reached down, and almost at the point of giving it a gentle flick to the right with my fingers a shrieking pain immobilised me.
I was both dumbfounded and in agony. Putting weight on my left leg hurt, and even standing up straight hurt. My mind was racing.
Your're only as strong as your back.
One of my instructors was fond of saying "you're only as strong as your back", and my back felt like it was permanently out of action. Was I ever going to be able to exercise again? Was this going to be what life was like for the rest of my life? Had I pinched a nerve, would it always hurt? I was now sweating more from fear than from pain!
From what I see around me, it seems that the older we get the more we become afraid of strength training - older people start to believe that it will do them more harm than good.
That's not the case, and you can do a lot with just bodyweight exercises to get started. Although you cannot reach the ultimate strength outcomes without heavy weights e.g. deadlifts and cleans - you can still achieve enormous benefits by just doing bodyweight exercises. And of course you can do those yourself at home.
Still, access to good equipment at a gym and a trainer, at least initially, is an advantage. Some basic knowledge also helps, and my four principles below will give you a great head start.
Since I was diagnosed at 50 with Type 2 diabetes I've been learning how to do bone-building body-shaping training for people our age. You can too. It's your choice. Walter