If you are looking for a real challenge, then try doing the RKC Plank. Invented by a former Soviet special forces trainer, ...

Burpees are a popular exercise, but they can put a lot of stress on your joints. You can swap burpees for other lower-impact ...

Plank jacks are a dynamic exercise that combines the core-strengthening benefits of planks with the cardiovascular boost of ...

Why one trainer calls the plank variation "no joke." ...