The old saying goes: abs are made in the gym, revealed in the kitchen.
Not saying it’s easy, and no it isn’t as simple as calories in, calories out, but it is close to that simple. Working out, running, weightlifting, all that can happen later. Eating “right” and just walking a lot can induce a lot of positives.
Yeah, it's wild how much you need to pay attention to diet to get those abs to show. I don't work out for aesthetics, but I train pretty hard for my age (40 -- muay thai a 2-3x per week, kettlebells a couple days, ashtanga yoga a day or two, and I'll throw in 5 mile runs here and there in a week).
I'm always around 12-13% body fat, but to get them to show, absolutely, it's all diet. I'm vegetarian, so that probably works against me, but I've never had that 8% body fat ripped look even with all the activity I do in a week.
Not saying it’s easy, and no it isn’t as simple as calories in, calories out, but it is close to that simple. Working out, running, weightlifting, all that can happen later. Eating “right” and just walking a lot can induce a lot of positives.