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.
To do it: Start in a plank position with one small towel placed under each ball of your foot, legs together. Bring your left knee in towards the right side of your chest, squeezing your abs. Then, straighten your right leg back out to full plank and bring your right knee in towards the left side of the your chest and back out to full plank. Next, draw both knees into your chest at the same time and then slide your legs back out to full plank. That’s one rep. Build up to 3 sets of 12-15 reps (resting in between).
7. Don't be disappointed if you can't achieve a well-defined six-pack. Because of your genetics and age, you may not be able to get the six-pack you want, but you can still be healthy, Hagensick says. "To be healthy, you have to have a certain percentage of fat. Some people simply have more fat than others around their midsection, but they can still improve their overall eating habits and exercise routine."
“For me, getting a six-pack was about paying attention to what I was eating and lifting heavy weights at CrossFit. I do have a semi-strict diet, and I loosely count macros (focusing on daily carbs, protein, and fat intake rather than blindly counting calories) to stay balanced and on track. It sounds like a lot of work, but it really isn’t. Eventually, it just became a part of my lifestyle, and it’s something I enjoy doing. I even started a custom meal-plan business based on macros because I had such great results!” —Tina Haupert, @carrotsncake