After the client has been medically cleared I do an assessment to see if any corrective exercises need to be incorporated. From my experience most clients, especially those who have been mostly sedentary, have some form of correction that needs to be addressed. For instance they may have difficulty keeping their feet from turning out or their knees from turning in or going forward when performing a squat. That is just one example but I address those needs first as well as basic core and balance conditioning. I also focus on light cardiovascular exercise as others have mentioned above. My goal is to get them comfortable with moving and if they enjoy what they are doing they will continue to do it. I also want them to be successful at something which intially may be simply doing 20 minutes on the bike or treadmill a few days a week. That will make them more confident to try new things as I am simultaneously aiding them in strengthening their core and helping to build their stability and learn proper form for the challenges that I will present to them in the future sessions.