To improve your core strength, you should keep your abs tight all day.
AB FACT Free the belly! “You wouldn’t walk around with your glutes contracted all day or your arm curled halfway up, would you?” says trainer Galina Denzel, coauthor of Eat Well, Move Well, Live Well. “Keeping your abs pulled in for all that time can put extra pressure on your stomach, uterus, and bladder and decrease the volume of your
lungs.” Training those core muscles correctly during your workouts— learning how to engage them and keep them that way while doing moves (see Myth 6)— will teach them to automatically kick in to stabilize you.