The simplest way to increase the difficulty of sit-ups is to add some weight. You can add a dumbbell, kettlebell or sandbag.

When most people think of a strong core or achieving abs, the first exercise that comes to mind is often sit-ups. While sit-ups have long been a go-to for strengthening the core, they're not always ...

YOU WANT BIGGER arms and a chiseled chest. Oh, and don’t forget stronger legs—super important. Oh, and a resilient core, too! So the last thing you want to do is train your hips—we get it. But here’s ...