Whether you are just recovered from your illness, been lazy going to the gym, birth of a chile hitting the plateau or anything that stop you from exercise. Going back is a challenge. You either can be unmotivated or very eager to start.
Although long long time ago you were a top athlete or top gym freak, your fitness level won't be the same as you were before. Your muscle mass is different from now and then. Your metabolism has changed. Thus, it's wise if you consult with physician before you start, especially for those who has just recovered from an illness. For the first goal for your comeback, just make exercise as a habit first.
Starting easy, don't be too hard on yourself. You'll get your pace.
Do some gym walking, perhaps your old gym already a little bit too rusty. Perhaps there are new gyms that just opened.
Find out why you stopped going to the gym earlier? Discover new you by making fitness program that suit you. Hire a personal trainer if necessary. He/she can help you when things get rough.
And don't forget to keep track of your progress.
Welcome back to healthy life.....