What does the woman most probably do?

W: Hello Tim, long time no see?
M: Yeah, Susan. I have heard you took many courses this semester.
W: Well, I just want to keep myself busy. What’s keeping you busy?
M: Doing exercise.
W: Oh, I can tell, your muscles look much tenser. What have you been doing?
M: I do different things for different parts of the body.
W: Oh yeah, tell me about it.
M: Well, I get up early in the morning and go jogging. That’s good for your whole body. Then I do sit-ups for my stomach and pushups for my arms. On the weekends I go bicycling which is good for my legs.
W: That sounds like a good plan. I should do something like that for myself, but I think it takes a lot determination to keep it up.
M: Yeah, it’s hard in the beginning, but it soon becomes a routine in your life. Remember Kitty, she is having an aerobic class each week.
W: Oh, really? Can you tell me the phone number of the fitness center? I guess people at our age should start paying attention to doing exercise every day.
M: Yes! But you’d also watch your diet. Don’t eat too much sweets, heavy food and salt.
W: Thanks!