Doing dedicated ab workouts one to three times a week can yield positive results, so long as it's part of a well-rounded fitness routine.
Best Lower Ab Workout for Men (Only 6 Minutes) - ATHLEAN-X
8 Ab Exercises You Can Do Before Bed for Toned Core
How Often Should You Work Out Your Abs? Plus Tips from Celebrity Personal Trainers
How Many Times a Week Should You Work on Abs?
How Long Does It Take To Get Abs + Tips To Make It Quicker – Fitbod
The Best at-Home Ab Workout: 10 Must-Do Ab Exercises
5 Of The Best Core Exercises You Should Do Everyday
The 9 Best Ab Exercises You Can Do Without Equipment
7 Best Barbell Exercises for a Strong Core - Muscle & Fitness
Core workouts at home: Try these beginner workouts & exercises