I've always been slim so exercise never seemed necessary. Exercise was for other people. I felt too inhibited to be seen doing exercise. In my 20's I had back/shoulder/neck problems due to complete lack of exercise. Despite it scaring me I still didn't exercise. Late 20's and a friend encouraged me to start cycling. This helped my legs and heart. Late 30's and it eventually dawns on me I should exercise other parts of my body as I had an inability to perform some fairly basic movements: * I couldn't windmill my arms as a small sharp pain inhibited motion (impingment?) * I couldn't touch my toes * I couldn't sit cross legged * I couldn't crouch * I couldn't sit in a kneeling position * I couldn't do a headstand (even getting into a starting position felt bad) * I couldn't do push ups etc And compared with a lot of people my age I was in good condition! You're still young, you can prevent yourself getting to that stage. You will be grateful later in life that you did. Life does get better, but you probably don't believe it can right now so just take the smallest of steps to begin with to improve your quality of life and until they become natural to you.