Core Workout: Plank Exercise!
Jock Workout: http://www.daveywaveyfitness.com/jock
Your core muscles are all the muscles around your pelvis and trunk. Strengthening those muscles should be a part of every fitness program, and it may mean more than doing the occasional sit-up or crunch. This plank exercise is a great way to target your core.
According to the Mayo Clinic, there are 7 important reasons to exercise your core. Strengthening your core:
Improves balance and stability.
Doesn't require equipment.
Helps build your abs.
Makes it easier to do most physical activities.
Doesn't take a lot of time.
Can be done at home - or anywhere else!
Helps you reach your other fitness goals.
In addition, I'd like to add that a strong core can help prevent lower back pain and improve your posture.