Pulling Mechanics

Hold on and Don’t Let Go!

By Ashley Mak

 

Hanging on a pull-up bar, what grip should I use?  The purpose is to explain the mechanisms of the underhand grip and its difference in uses and muscles compared to the overhand grip.

The other day I was discussing the differences between the overhand and underhand grip while hanging on a pull-up bar.

Alison asked me whether or not I thought the underhand grip made any difference in difficulty during core work.  This sparked an interest to investigate.

 

So I researched and watched Alison do her workout with the underhand grip and noticed a few differences-

(In no way is this a debate on whether or not the pull-up or chin up is better, I am simply pointing out the differences for each grip while in the hang)

  • In the underhand grip, the shoulders are positioned into a more externally rotated position, which is the ideal position for end range overhead movements
  • In the underhand grip, the upper and lower back are placed onto more tension, creating a stable spine rather than causing a hyperextension moment in individuals who have trouble maintaining the hollow position (Hollow Body Video)
  • The underhand grip facilitates the maintenance of a neutral spine especially in the hang and with core work

 

Let’s talk about each point:

 

External rotation of the shoulder

In Kelly Starrett’s Becoming a Supple Leopard, he discusses the laws of torque and stability.

Torque is defined as a force along a rotational axis.  The generation of this in the hip and shoulder joint creates a stable surface of movement.  The proper production of torque will allow maximal force and power generation, as well as increase performance.  However lack of appropriate rotation force will result in a loss of power, performance, and an increase in injury risk.

K-Starr also states that both midline stabilization (bracing) and torque are two parts of a unifying system that work with each other.  A deficiency in spinal stabilization will lead to a decrease in rotation force production and vice versa.

 

The two laws of Torque as defined by K-Starr are:

  1. To create stability with the hips or shoulders in flexion, you need to generate an external rotation force.
  2. To create stability with the hips or shoulders in extension, you need to create an internal rotation force.

(The incorrect application of rotational force to a joint in either flexion or extension, would result in a loss of performance and an increase in injury risk)

 

Just Hanging Out

This is what happens when hanging on the pull-up bars

  • Near end range shoulder flexion
  • Distraction force of body weight onto the glenohumeral joint
  • Medial rotation and horizontal abduction of the scapulae

 

With the overhand grip (in addition to the hang position)

  • Shoulders are internally rotated at the glenohumeral joint

With the underhand grip (in addition to the hang position)

  • Shoulders are externally rotated at the glenohumeral joint

 

The hang position is very important because it is the start and end point of pull ups, leg raises, and many other body weight movements on bars, rings, ledges etc.

While in the overhand position, you could still create an external rotation force by breaking the pull-up bar in half to create that stable spine.

However, there are limitations to this grip:

  • Not having enough strength to create the external rotation force on a fixed object will result in a loss of torque and stability in the shoulder.
  • Not having the ability to organize the spine in the braced or hollow position can lead to a reduction in the external rotation force of the shoulders, reducing the stability
    • Example- the ribs flaring out at the bottom of the hang

By assuming the underhand grip on the bars:

  • The shoulders are already placed into the externally rotated position
  • Reiteration of the first law of torque, a position of stability for the shoulder in flexion is external rotation
  • This allows you the opportunity to focus on organizing and creating a stable spine in the hang
    • Example- pulling the ribs down

 

Upper and lower back stability

Let’s talk about the main movers of the shoulder during pull-ups and chin ups.  The latissimus dorsi is mostly responsible for shoulder extension, which brings the elbows down and pulls you up over the bar.

Actions of the latissimus dorsi are:

  • Shoulder extensor
  • Shoulder internal rotator
  • Shoulder adductor
  • They also originate from the spinous processes from the thoracic all the way down to the thoracolumbar fascia (by the pelvis)
  • Any movement in the opposite direction of the action of the lats cause them to elongate and produce more tension
  • Any movement in the same direction in the same direction of action cause a shortening of the muscle fiber
    • The internal rotation of the shoulders in the overhand grip will reduce the resting tensile forces of the lats at the bottom of the hang, making it more challenging to create a stable spine.
    • This is caused by the the muscles being placed into a mechanically disadvantaged position
    • When muscles are shortened beyond their resting length, they are not able to produce as much force as they would at their optimal length
  • External rotation of the shoulders in the overhand grip places more tension on the lats, reducing the amount of effort needed to create a stable spine while hanging.
    • The tension will prevent over extension of the low back when the core muscles are weak or fatigued and are able to produce limited force and stability

 

Using the underhand grip is great when focusing on core work such as L hangs, toes to bar, knees to elbows, etc. because it reduces the amount of effort needed to create a more stable spine through externally rotating the shoulders.  It is helpful for those athletes who have not quite developed the strength in their shoulders to safely hold themselves.

As the athlete becomes more advanced and is able to develop strength in the shoulders while also being able to organize the spine, flipping the grip to overhand will be useful in creating a greater challenge and stimulus.

 

Take Home Points:

  • Assuming the Underhand Grip in the hang places the shoulders into an externally rotated position.
    • This generates torque and places the shoulder in a more stable position.
  • In addition to the external rotation of the shoulder on the joint itself, the Lats are placed on stretch allowing more tension to be generated around the shoulder.
  • The underhand grip will be a useful tool for any hanging core work used when an athlete does not have sufficient strength.
  • Organizing a stable spine and shoulder is needed to maximize athletic performance, maximize power/force output, and minimize risk of injury

 

If you have tried experimenting with different grips while hanging and or are interested in trying, I would be very interested to receive your thoughts on how it worked out for all of you!  Talk to you soon!