Just start! Every little bit makes a difference. Build your endurance and your core, to improve your balance and cardiac fitness.
I'm going on 67 this year and I have a free Black membership at Planet Fitness, with my supplemental (part G) plan. I have no excuses not to go.
I'm in there every other day rotating my cardio workout on the treadmill, Elliptical, and the stair climber before I start lifting. I am still able to do a 4 minute plank and 8-10 dead hang pullups. I didn't get there overnight. You just have to be disciplined and take it slow to start. I don't do any deadlifts or squats anymore. It's not good for the back or knees at our age. I really don't want to hurt myself anymore either. I'm 5'8" and 171#, but unfortunately I've shrunk about 1.5".
I've also worked up to being able to do a set of 3 reps on this supine bench, with three 45# plates on each side. The bar weighs 10#, so that's 145# on each arm.
I hope this motivates you.
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