38 here. Figure best it's ever been.
Yes, sorry but it is diet and physical exercise. However think of it as lifestyle!
For what you eat - don't think so much as strict what you can't eat, but lots of goodness that you can. After a while your body will not want the really crappy unhealthy stuff so it easy. Look at vegan food basics, super low fat but lots of food that doesn't feel limited, then if you want to stay eat everything diet, add in your fish and white meat protein.
For what you do - find something you love that you can find in your schedule and do as much as you can. Endorphin rush will keep you going back, have you in super shape plus let you eat without feeling you can't. Yoga is amazing, I also work out through in gym cardio, but overall prefer yoga. You don't need hours and hours in the gym, just go for it when you are there, you are supposed to sweat.
Positive not negative, eat lots of healthy, replacing with and adding in healthy rather than refusing yourself. Physical exercise that you love.
Lifestyle:)