What is my hand doing, what should my hand be doing, and why does it matter when referencing a pullup bar?
Let’s talk about this, I don’t think a week goes by without me saying the words “thumb around the bar” while coaching group classes. Often I am met after class with the question why. First, let me just say that is my favorite question, without context it is senseless; those that choose to learn more, grow wiser. Humans are one of the few species that have an opposable thumb, and we can move are opposable thumb more dramatically than any other primates on the planet. Why thumb around the bar, first and foremost it’s about safety.
Your thumb acts as a check safe against aggressive swinging. In a wod scenario, we are pushing the pace up to ninety percent. Having the thumb around the bar adds an additional safety mechanism to ensure we don’t fly off the bar while moving at high intensity. If anyone is struggling to grasp this idea, or thinks this can’t happen to them needs to watch Nick Urankar’s unfinished Fran.
Now we discuss the phrase “but it’s harder with thumb around”; of course it is, that’s why we do it. It’s the hard that keeps us coming back, it’s the hard that makes us stronger. When breaking this down biomechanically it starts to showcase the true power of this scenario.
Ultimately, thumb around the bar is about creating a more stable shoulder and strengthening the joint. When thumb is around, it forces the athlete’s shoulder to stay in flexion and external rotation; this is allows the athlete to generate torque in the back swing for the joint and truly services the shoulder. When thumb is over the bar, the athlete loses the ability to generate torque; when he/she hits the bottom of the swing, their shoulders internally rotate and the shoulder creates capsular slack. Capsular slack is destabilizing the shoulder and wrenching on the connective tissue, which is really bad if you haven’t guessed. The athlete takes this capsular slack and destabilized shoulder to create a false torque at the expense of the rotator cuff muscles and connective tissue around the joint. So while it may be easier on your muscles, its way harder on your joints and ligaments. Thumb over bar, forces your muscles to do the work (which is why we are in the gym, to strengthen our muscles) thumb over the bar in a standard kip, pulls on the ligaments and connective tissue which will weaken the structure, if not destroy it over time.
Last but not least, translating best practice out to other movements. Using a thumb around the bar forces the grip to work harder, which in turn builds more grip strength. Grip strength is one of the most underrated strengths in the fitness world. Where is grip strength most important? Powerful grip
strength is needed for the following movements: Pullups, Toes to bar, knees to elbows, deadlifts, cleans, snatches, and kettlebell swings. If you want your pullups to build strength in the other movements, I would suggest thumb around the bar.
Of course, there is always going to be outliers; can I internally rotate with thumbs around, yes, can I stay stable with thumb over, yes. The choice is yours, I just display the facts.