The 52-year-old is currently filming Sanjay Gupta's crime thriller Shootout At Wadala.
Kapoor told The Times of India: "It is very important to have a good physique. Health helps you in every sphere of life. During 24 hours, you use your body for everything. You work with your body, study, and everything else.
"So it's your duty to pamper your body at least for an hour everyday. Exercise gives me energy to work for rest of the day. When I don't exercise, I don't feel good the entire day.
"People tell me that I look much better and fitter now. I am trying my best to do this. I focus on keeping my mind fit, then food and exercise."
In November, it was reported that the veteran star was bulking up for the film, which co-stars John Abraham.
Kapoor recently spoke about performing his own stunt sequences for the upcoming Tezz, describing them as "tough, but not dangerous".