It is not a cool guide for bikini season, one all of the photos are people who wouldn't wear bikinis, and two seeing those muscle groups which is the implied goal of bikini season, is not about muscle mass but body fat percentage..
Came here to say exactly that. In general, abs are a muscle group you shouldn't bother about in your workouts.
Do more complex, full body exercises rather than training such small, specific areas. If you do dead lifts, push ups, pull ups, squats etc. your abs will be involved everywhere implicitly and grow proportionally.
Crunches, curls, shrugs, shoulder press etc. that target small muscle groups are all only relevant if you want to max out an already well-trained body.
If your fat percentage is high enough then no amount of training will give you visible abs. On the other hand; if it's low enough you'll get visible abs with zero training.
I get that diet is the most important thing for abs but, are there excercises to burn fat specifically in the abs area?
I'm pretty fit and my weight is ok, or even a little below what I would want, but my abs are not visible
It's not really a proper guide, like, it doesn't make sense anatomically. Upper and lower "sixpack" muscles aren't different muscles, the squareness of them is just fascia on top holding things together. I don't know what definition of "core" they have here, it also makes no sense. If you want to exercise, good, but find a better guide.
Do you hate yourself? Do you enjoy suffering? Do you like being sweaty and never seeing any return on investment? Have you heard people say that it can make you feel good but never experienced any evidence to prove it? Try exercise today!