What should I do to reduce my tummy?

What should I do to reduce my tummy?

I am 69 years old, and  I work out almost every day.  I work 12 hours a day. I weigh 142 lbs., Height 5' 11" and waist size 34 inches.  I need your help to tell me what I should do to reduce my tummy. Also, I can use some more energy. –Aya Reducing your tummy when...