Wendy & Christine have given you great advice so far. I have a few clients myself who are in their 80’s. Actually the three of them (all women) get around pretty well, without the use of any walking aids. At that age, one of the greatest concerns is falling. I definitely incorporate balance exercises into their workout sessions, in addition to their strength, CV & flexibility exercises. So far, so good. Strength training- wise, I keep the movements simple, mainly using light dumbbells, tubing & some easy-going body weight exercises. I take them to the point where they’re just slightly past their comfort zone. I do push them, but only to the point where they start asking me “how much do they have left” – you’ll see what I mean. Good luck Tom.