https://www.yogajournal.com/how-to-challenge-poses/5-reasons-basic-physics-says-its-never-wise-to-jump-back-to-plank-pose
5 Reasons Basic Physics Says It’s Never Wise to Jump Back to Plank Pose
Warning: This article contains more physics than we’ve seen since high school. But yoga teacher Leah Sugerman happily dove into the science behind the controversial cue—and its safer alternatives. (Yoga nerds, you’re welcome.)
I hear the cue “Jump to Plank Pose” with alarming frequency in the yoga world. Time after time, city after city, studio after studio, teachers have instructed me to jump from a Half Standing Forward Bend at the top of my mat into a High Plank position—instead of Chaturanga. Many teachers will tell you that with proper strength and control it is possible to execute this transition safely. Many others will tell you that it’s impossible to jump back to Plank with anatomical integrity. To actually break it down, not only the anatomy, but also the physics of the transition needs to be considered. Take a look at what science says about this powerful movement to determine for yourself whether it is a wise option to offer your students or yourself in yoga practice.
5 Reasons to Stop Jumping to Plank
1. First off, landing in Plank just feels awkward.
Something that has been ingrained in me, since my first childhood ballet class at the age of two: Always, always, always land with bent knees after jumps. This seems intuitive when you actually jump—you naturally bend your knees to land. Imagine jumping down a small flight of stairs and landing with your legs straight. Ouch, right?
The instinctual bend keeps your knee joints (and everything above them!) safe. To understand that, a little more on joints: Joints are where bones articulate, or meet. These meeting points are ingeniously designed to absorb shock mainly through their cartilage and soft tissues but also by allowing for movement. When force is applied to a joint, it can move to both slow down the impact and distribute the force over a larger area. However, when you apply significant force to a joint without moving it, as in jumping into Plank, a fixed, bone-stacked position for example, the ligaments within the wrists, elbows, and shoulders bear the brunt of the impact. One of the most common causes of ligament injury is “landing awkwardly,” like in a bone-stacked position. That brings us to our next point.
2. Your connective tissues aren’t elastic.
Super quick (and, therefore, simplified) anatomy briefing: ligaments are fibrous connective tissue that connect bone to bone. Tendons are fibrous connective tissue that connect muscle to bone. Neither are elastic; they’re viscoelastic, which is a fancy way of saying that they don’t allow for unlimited, but rather very, very limited mobility. When under stress, they can gradually strain and then return back to their normal state once the tension is released. However, if stress on a ligament or tendon is significant forcing it to stretch far beyond its natural capacity, then it will not be able to return to its original state. The same is true when stressed for a prolonged period of time—or repeatedly (such as day after day in asana practice).
3. The basic physics of the transition make it unsafe.
A very basic understanding of physics demonstrates how jumping to Plank is inherently injurious to the body. In the transition to both Plank Pose and Chaturanga Dandasana, the point of contact with the floor is the palms, and the point of pressure is mainly in the wrists, elbows, and shoulders. Imagine that the wrists are the pivot of a seesaw, and for this seesaw to remain balanced that point of contact must have an equal balance of torque on either side of it. That means that if the weight at one end of the seesaw is more than the weight at the other end, then the heavier weight must be closer to the pivot point than the other to maintain that balance.
In Plank Pose, the angle at the shoulder joint is 90 degrees and the angle at the elbow joint is 0 degrees. As you change this shape to Chaturanga, the opposite occurs: the angle at the shoulder joint becomes 0 degrees and the angle at the elbow joint becomes roughly 90 degrees. This transfer of angles also significantly transfers the distribution of weight. In Chaturanga, the weight from your waist to your head is distributed in front of your elbows and wrists. The weight of your body below your waist is distributed behind your elbows and wrists. This creates a roughly equal balance of weight from head to heel in the body. That balance applies significantly less pressure in the joints, compared with Plank Pose, where the vast majority of your weight (everything except the weight of your head) is unevenly distributed behind your wrists. That’s not to say that Plank Pose is inherently bad for the body. There’s a big difference in practicing Plank Pose as a static posture versus a dynamic transition. Let’s take a look at that next.
4. The force of the transition adds shock your body isn’t prepared to absorb.
One of the most useful equations of classical physics is this: the force on an object is equal to the mass of an object multiplied by the acceleration of that object. You are creating force by jumping to Plank—that is, a force equal to your own body mass multiplied by your increase in speed in the transition. Landing in Chaturanga instead more evenly distributes this significant force across the seesaw of the body (as explained above).
Furthermore, the static and dynamic biomechanics of this transition cannot be overlooked. This is because of an important little thing known as velocity. Velocity is the speed of an object in a given direction. If you were to walk forward and back, forward and back always landing in the same spot, you could create a lot of speed but your average velocity would equal zero since there is no directional movement when you always arrive back where you started. Similarly, when you jump from Ardha Uttanasana to Plank, there is no directional movement in your upper body. Your shoulders stay aligned over your elbows and your wrists throughout, so your velocity is zero. When you jump from Ardha Uttanasana to Chaturanga, however, your upper body moves forward in space, changing the angle between your shoulders, elbows, and wrists, which creates velocity. When you jump back, you want to create this velocity because you want the weight of your body to move in a forward vector to equalize your body weight over your point of contact with the floor (your seesaw axis: the palms). This simple forward motion more evenly distributes your body weight so that less force is exerted on one joint alone.
5. When you don’t let the joints absorb shock the way they’re designed to, the rest of the body has to compensate.
Jumping to Plank forces the wrist, elbow, and shoulder joints to absorb a great deal of the shock that would otherwise be dispersed in Chaturanga. That can critically compromise the integrity of those joints by damaging their ligaments, tendons, cartilage, bursa, and more. But the excess force can also move up through the body and be displaced across other joints, causing pain especially in the notoriously vulnerable lumbar spine.
Plus, your big toes are at risk, bearing the brunt of the landing. Typically the first point of contact in a jump back, they absorb all of the impact from the hard landing with the majority of your weight behind your seesaw axis. This can (and definitely does) break bones in the toes.
3 Safer Alternatives to Jumping Back to Plank
Will jumping back to Plank kill you? No, likely not. But will jumping to Plank (especially repeatedly over time) significantly increase your risk of injury and long-term debilitation in the body? My resounding answer is yes. I highly recommend you consider all these points before determining whether jumping to Plank is safe and—more importantly—beneficial to your body in the long run. Because, after all, isn’t that why we practice yoga in the first place?
About Our Expert
Leah Sugerman is an international yoga teacher, anatomy lover, writer, and passionate world traveler. From Leah's very first encounter with yoga, she was hooked. She fell in love with the pure dichotomy of the practice: the stark contrast between the strength and power compared to the grace and surrender. She enjoys the beautiful dance between the two extremes that happens on (and off!) her mat every day. A lover of life, words, anatomically safe yoga, travel, handstands, and, most of all, the beach, Leah teaches classes, workshops, retreats, and trainings both online and around the world. Connect with Leah and follow her teachings and travels on Instagram, Facebook, Twitter, and her website.
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