Core Strength - Power of Proximal Acceleration

We all know core strength is important for running. It helps hold our body upright, regulates breathing and gives us explosive power. Planks and crunches are typically part of a runners strength routine. However, planks are a static exercise and crunches accentuates a flexed position. Do those exercises work the muscles specific to running? What other exercises load the core which most resembles running?

A closer look at the running form shows our pelvis rotates with each stride. While one leg is forward the other leg is behind. Meanwhile, our arms are moving the opposite direction of our legs. Our   abdominal muscles are being stretched with each stride.
Opposing motion between the arms and legs helps to stretch the connective tissue of the anterior core in a rotatory fashion. This is important because rotation provides the strongest load (think of the glide versus spin technique in field events).  The stretch of our anterior trunk loads our core, similar to the recoil of a slinky, which helps to accelerate our leg forward.

Note the stretch that occurs across our abdominals

A key component of spinal mobility is rotation occurs in the thoracic spine and the pelvis. The lumbar spine has very little to no rotational mobility. In order to effectively load the core, it is important to stretch the upper back and hips appropriately. Here are 2 links to upper back and hip stretches.
http://3drunner.blogspot.com/2015/03/spine-stiffness.html
http://3drunner.blogspot.com/2014/06/ankle-sprain-how-thoracic-spine-and-hip.html

EXERCISES
Planks with Pelvic Driver
Assume the normal plank position. Keep your arms straight rotate the pelvis towards the floor. To help load the frontal plane, move the pelvis side to side.

Resisted Pelvic Driver
Equipment needed - A belt and resistant band
This exercise requires a bit of creativity. Tie a resistant band to a belt. Then wear the belt. Attach the band with the belt around a post or fence. Place one leg forward with the band from behind. Adjust the belt so the band is coming from behind towards the side of the leg that is forward. Shift weight forward as you push the pelvis forward.

Stride Stance Ball Catches
Equipment needed - Ball or medicine ball
Stand with one foot in front. Use a ball and throw to a partner from the side. This exercise provides a stretch to the abdominals in a rotatory motion. A second throwing position can be throwing it overhead which provides a load in a different plane of motion. Try catching with one hand.
Throw and catch with the arm which is same side front leg.

Recommended 12 - 15 times of each exercise up to 3 sets

TRANSITION TO RUN
During strides or warm up, implement a pelvic drive while running. Visualize a rope in the front of your pelvis pulling your body forward with each step.

These exercises paired with a traditional strength routine will attack the core muscles in all dimensions.  Proximal acceleration is vital for the mechanics of numerous athletes such as golfers, throwers and even swimmers to produce force. So why not runners?!