Making the leap–without the leap–from inverting on the ground to inverting in the air on your aerial apparatus, most specially vertical apparatus, can be quite a big leap-pun intended. The advantage of the push off the mat–or the bar of your bar apparatus–is the transfer of force from your legs pushing into a resistance and back up into your body to propel you upside down.
Many people struggle with inversions and they struggle even longer to invert cleanly, i.e. bent arms and shoulders engaged, pulling the knees up, the unhinging the elbows as you tilt back to bring hips to wrist into a stacked inverted position. Add the desire for straight legs and this becomes even more challenging. (For this post I am going to focus on bent arm inversions, straight arm inversions are more advanced and I’ll save that for a future post.)
Anatomy of Inversions
Inversions in general are asking the body to coordinate many areas of the body all at once: stabilize the shoulder girdle, contract the core, hip flexors and lats and eccentrically load the biceps all to move the hips over the head and shoulders. Let’s look at these individually. (The muscles listed below are just some of the muscles involved, not all of them and not all of their actions, but these are the muscles I’ll focus on for this post)
The Shoulder Girdle
First we need to stabilize the gleno-humeral joint.
- Starting with the deepest muscles–AND THE MOST IMPORTANT–your rotator cuff muscles. These muscles are stabilizing the head of your humerus (upper arm bone) in the shallow shoulder socket (the gleno-humeral joint). These four muscles need to be strong for many reasons to participate in circus activities, but holding the head of the humerus in the center of the socket to decrease wear and tear to the gleno-humeral joint is important for the health and longevity of the joint.
Then we need to stabilize the scapula. This comes in two parts: the first being when we are still upright. The second being as we invert and finish in the inversion.
- We want to start with good placement of the scapula on the posterior rib cage. To do this we want to engage (isometrically contract) the muscles surrounding the scapula that will keep them in the desired placement throughout the inversion.
- Mid and Lower Traps keep the shoulders from elevating towards the ears and protracting away from the ‘shoulder set’ in relation to the spine.
- Rhomboids (major and minor), similar to mid traps, these muscles keep the scapula retracting towards the rib cage to avoid excessive protraction out of our set shoulder position.
- Serratus Anterior are preventing the scapula from winging away from the rib cage as well as assisting to balance out the contraction from the rhomboids and mid-traps to hold the scapula in the set position.
Other muscles that are isometrically contracting to keep your shoulder and arm positioning.
- Lats are helping to squeeze the humerus to the side of your rib cage because one of the main actions of the lats is bringing the humerus back down to the side of the body from a raised position. This is because the lat attaches on the humerus. Therefore contracting the lats will keep the humerus squeezing the ribs while moving through the inversion.
- Teres Major is the little lat and also helps keep your humerus pressed to the side of your body throughout the inversion.
Muscles eccentrically and concentrically contracting in opposition to one another.
- Biceps are contracted in a shortened position while upright. This contraction is the reason for the flexion (bent arm) of your elbow. As we invert the biceps will need to lengthen, but will still be under load, this is an eccentric contraction. Eccentric contractions, a slow controlled lengthening in the muscle under load, is quite difficult and also a great way to build strength.
- Triceps are elongated and isometrically contracting to stabilize the elbow in flexion while we are upright. As we tip back into the inversion the triceps will concentrically contract into a shortened position as the elbows extend straight.
The action of inverting and your upper body
As we move through the inversion all of the above muscles: rotator cuff, traps (mid & low), rhomboids and serratus are all working to stabilize the scapula and the gleno-humeral joint. As we tip into the inversion the lats and teres major have to work extra hard to keep the humerus pressed to the side of the body while the biceps and triceps are changing their length and contraction type to get your hips over your head and shoulders.
The scapula themselves don’t actually move from their ‘set position’, all that happens in the upper body is the unhinging of the elbow via your biceps and triceps.
Spine and Pelvis
First, and foremost–even before our shoulders set into their position, we need to engage through our core.
Stabilizing the Spine
Engaging our core is to stabilize our spine and keep it safe from any shear forces as we go through our inversion. Without an engaged core we run a higher risk of injury, or eventual injury to our backs.
We want to start with our deeper core muscles first, our transverse abdominals and our pelvic floor, then adding in the external obliques to knit the rib cage together. If this seems like a foreign concept, then read my previous post on core activation. Stabilizing the spine needs to first start with these muscles, there is very little activity from our rectus abdominus muscles (the six pack abs) when it comes to bent arm inversions and this is because our spines shouldn’t be really all that flexed and spinal flexion is the rectus abs main action. Of course if the hip flexors aren’t very strong then inverting does require more spinal flexion and more rectus abs recruitment, but the more compact you make yourself, the higher and closer your knees are to your upper body, the less the spine needs to flex-which is ultimately better.
Activate the Muscles of your Pelvis
Once the deep core is activated then we need to activate the hip flexors (psoas and rectus femoris-a quad muscle) to pull the knees up into a froggy position so that we are in a shortened leg lever to invert. The more we can pull our knees to our chest/out to the side in the froggy position the easier it is to invert. The closer the legs can pull into the torso, the tighter the ball your body makes, the easier it is to tip back. If the hip flexors lack the strength to pull the knees up towards the armpits-either in front of the body or out in froggy position-the harder inverting will be or the more reliant on spinal flexion your body will be.
In the videos below you’ll find several exercises that are great for developing strength and stability through your shoulder girdle and strengthening your hips flexors to pull your legs higher. For strengthening the deep core musculature please see this blog post for activating your deep core as well as the supplemental video below. You will also find below some links to additional videos for more exercises or more details on the specific exercises.
- Strong point hold. Demonstrated both on trapeze and silks. This develops the bent arm strength of holding yourself and the strength to keep the scapula in their ‘set position’.
- Squeeze upper arms to the sides of your body. Make sure shoulders are not raising up towards ears or that your hands are coming in towards your sternum (breast bone) in what I call the cuddle position. My cue for this is ‘feel the W’: the muscles on the outside of the scapula, the bottom and the inside: the lats and mid/low traps working.
- Hold for 30 seconds.
- Tucked Rockbacks. Also demonstrated on both trapeze and silks. This helps to develop stability and strength in the shoulder girdle throughout the movement as well as develop the strength to only unhinge the elbow. The Rockbacks also strengthen the core and hip flexors to maintain the tucked position throughout the movement.
- Make sure to maintain the scapula positioning, ‘feeling the W’ throughout the movement. Keep core contracted throughout as well.
- Do 5-10 tucked rockbacks
- Low Rows. Demonstrated on silks, but can also be done on a low enough trapeze. This exercises develops back strength around the scapula. Here is an alternate video demonstrating low rows.
- During this exercise make sure not to have the upper traps, where your shoulders and neck meet, contracting and doing the work. You should feel this in your mid back. This is another place where I cue, ‘feel the W.’ Keep core and glutes contracted. Elbows will go out to the side a bit, like you are rolling a boat, but in a diagonal plane, pulling the chest in line with the hands.
- Do 10 rows.
- Bicep curls on silks. This exercise can be also done with a trapeze or your standard bicep curl. This exercise is strengthening your biceps to help make the unhinging of your elbow under load easier.
- Make sure upper traps are not taking over this movement. Keep core and glutes contracted. Here your elbows will stay close to the body and really focus on bringing the hands in towards the shoulders, this ensures that the main joint moving is the elbow.
- Do 10 curls.
- Stir the Pot. This exercise is to strengthen your rotator cuff in a dynamic way. As an extra bonus it is a core exercise too! Here’s a more in-depth video.
- Set up in plank with forearms on ball. Pressing down into the ball from shoulders. Core, glutes and legs engaged.
- Circle the ball 5-10x in one direction and then repeat in the other direction.
- Side Lying External Rotation. This rotator cuff exercises is set up with your head propped up on your arm, pillow or yoga block and a rolled up towel or small pillow between your elbow and your torso.
- Exhale as you externally rotate the hand towards the ceiling. Feel the muscles on the scapula (specifically your infraspinatus) do this movement. Make sure not to feel your upper trap or to activate your lat with pulling your ‘shoulder blade in your back pocket’. Activation of the lat is counter-productive to this exercise.
- Do 10 lifts on each arm.
- Standing Straight Leg Leg Lift. This is to strengthen your hip flexors. This is both great for bent and straight leg inversions.
- Prop foot on an elevated surface where when you lift your leg you can only lift it about 2 inches. Inhale and engage your core and radiate that isometric contraction to the glute and the quad of your standing leg, to your quad of the lifting leg and up your body and out into your fists. You want to be squeezing/engaging your everything!! Keeping both legs straight, exhale and lift the leg off the elevated surface.
- Do 10 leg lifts on each leg.
- Seated Straight Leg Leg Lift. This exercise strengthens the same muscles as it’s standing version. Seated against the wall keeps you honest so that you can’t lean back or flex (round) your spine. Here is another video for additional seated hip flexor exercises.
- Sit with your hips, back and head touching the wall. Draw the pelvic floor up and knit the lower rib cage together with your external obliques, thus activating your core. Lift arms up so that you can’t use your hands/arms to push. Isometrically contract your quads. On an exhale, using your hip flexors, lift your leg up.
- Do 10 lifts with each leg.
Here are two more videos. The first is demonstrating another hip flexor exercise that will help strengthen the hip flexor and core for tucking your knees up during inversions–even helps straight legs inversions! The second video is an additional deep core strengthening exercise that also targets your hip flexors to help with your knee tucks, leg lifts and other inversions. With each exercise below perform 2 sets of 5-10 repetitions on each leg.
As always, feel free to contact me if you have any questions or even want to do any training together. I offer in person and online training.
CPT, TRX, PN1, 200 RYT, FMS2, FRC Mobility Specialist