A personal trainer explains how long to hold a plank for bullet-proof core strength and how to master the perfect plank form.

Antonela Roccuzzo, the wife of Lionel Messi, is not only known for her beauty and charisma but also for her sculpted abs.

Functional training is shaking up the fitness world with dynamic exercises that boost strength, endurance, and balance.

A staple of many core workouts, most runners will be familiar with the side plank exercise. But you may be surprised to learn that it's one of the best exercises you can do for working your deep core.

In fact, research in the International Journal of Sports Physical Therapy found that athletes with poor core strength (as measured by tests like side plank) have a higher risk of lower-back pain.