Got a chair?

Planks have been all the rage in the fitness field the past few years—they’ve trumped the crunch (and many other moves, for that matter) as the go-to exercise for strengthening the core muscles, the group of trunk muscles that surround the spine and include the abs, hips and glutes.

Regardless of your fitness level, you can easily start from zero to running 20 minutes continuously in 10 weeks.

Using ball exercises to workout and get lean is a fun way to mix up you workout, work your core, and get you back into shape.