I love working out, and a good workout challenge is even better. When I had the opportunity to try model Alexis Ren's viral ...

Discover the most effective 15-minute core workout routine from a certified trainer with 20+ years experience. Get defined abs in just 4-6 weeks with these 5 proven exercises.

Isometric exercises are meant to help strengthen muscles ... Begin lying on your front, propped up on your elbows. Engage your abdominal muscles and lift your hips and legs up into a plank ...

Seated ab exercises can help you strengthen your core ... muscular control and stamina from an isometric (non-moving) and isotonic (moving) position. How can I tone my stomach while sitting?