Warm up and cool down for 5 to 10 minutes. Go for a brisk walk or jog, do jumping jacks, run in place, or jump rope at the start of your workouts. Moderate aerobic exercise will increase blood flow to your muscles, which reduces your risk of injuring yourself. When you finish working out, cool down for 5 to 10 minutes to help your muscles recover.[11]
Go beyond crunches. Sims prefers exercises that challenge you to stabilize your core against imbalance or gravity, like a hands plank with dumbbell pull-through and ab roll-outs using a core-training wheel. "They challenge the entire core by resisting movement instead of creating it," she says of these moves, which she recommends doing in sets of 10 three times. You can repeat the series several times a week.
As they do, you should try to include at least one of the exercises described herein into your personal training program two times a week. These exercises can be made more difficult, but I seldom advise more than 10 – 20 slow reps on any of them. You should increase the resistance with these exercises rather than the reps; and if you’re working hard enough, you should only perform 2-3 sets per exercise. I would also suggest that you not perform any single exercise for more than three weeks in a row, since well-conditioned muscles adapt quickly to any exercise, and this adaptation must be minimized.
I am older turning 65 this year. I did the diet stuff about 8 years ago. In 2010 or so I was about 170 I had lost over 40 lbs. I was too sedentary. My diet which is more a way of life is mostly white meat. Milk must be skim, Drink water no soda. Eat lots of whole grains, veggies, nuts, seeds etc. Noticed maybe over a year ago if I breathed in I could see some abs. Now I don’t need to breath in. I have a handicap so am limited at the gym but do leg raises and use abdominal machines at the gym.I call mine a minor 6 pac.I don’t raise my shirt at the gym lol but have had a few stares from others as I guess you can see them through my shirt. So I think it does have a lot to do with diet but exercise will make them more prominent.
To do it: Stand with your feet planted 3-4 feet apart, toes slightly turned out, hands on your hips. Lower into a plie by bending your knees out over your toes and lowering your hips directly underneath your shoulders. Then, as your straighten back up, slowly lift the right knee up towards the right shoulder. As you go back into the plie, slowly return the foot to the floor. Be sure to move at a very controlled pace to really engage the obliques the entire time—on the way up and on the way down. Do 10 repetitions on the right side, then another 10 repetitions on the left side for a total of 20.

best ways to build core