Try this 5 minute plank workout to strengthen up your core and create lean abs! Planks are the rockstar of abdominal work. If you are unclear about the many benefits of the plank or if you want to ace your form, you might want to check out Perfecting You
This plank challenge workout could be the key to toned arms and flat abs. It takes about 20 minutes (there are modifications for beginners) and will leave your arms feeling like jelly — in the best way possible.