Beyond Proprioception Part 2: Sensory Integration and Interoception

In Part 1, we examined the visual, vestibular, and proprioceptive systems individually and how, in practice, balance is not governed by any one system in isolation. In Part 2, we will focus on how the nervous system is constantly integrating and prioritizing sensory information in real time. Understanding how this integration occurs allows us to teach more effectively and assess clients with greater precision. It also brings attention to an often-overlooked contributor to balance: interoception.

SENSORY INTEGRATION: HOW THE SYSTEMS WORK TOGETHER

What is sensory reweighting?
According to Lorenz Assländer, the process of adjusting the sensory contributions from our eyes, inner ear, and body to maintain balance is known as sensory reweighting. Essentially, the body shifts toward the most reliable source of information when another system is compromised.

Consider walking down a flight of stairs in the dark. You may reach for the banister or use your feet to feel for the next step because visual input is unavailable. The brain dynamically adjusts which sensory input to prioritize based on context. This process occurs continuously, often without conscious awareness, and becomes especially apparent when one system is challenged.

Two simple examples: When sensory input is limited, for example you have vertigo and vestibular feedback is reduced, the body increases reliance on visual and proprioceptive information.You’ll likely scan your environment more intently and be more sensitive to sensations like a change in air pressure. Also, when standing on an unstable surface like a BOSU, the body increases reliance on visual and vestibular inputs because proprioceptive feedback from the feet is less reliable. You’ll benefit from having a mirror or steady point straight ahead to focus on (visual) and you’ll be more sensitive to changes in your head and cervical alignment (vestibular). In other words, the brain reduces dependence on compromised input and amplifies what remains dependable.

HOW THIS SHAPES MY TEACHING

Understanding sensory weighting directly informs how I teach and assess. Rather than assuming a balance issue is purely muscular, I consider which sensory system may be underutilized or overly relied upon.

For example, a client with neuropathy may lack sensation in the feet and lower legs. In these cases, I emphasize visual and vestibular engagement: emphasizing eyes on the horizon, tracking movement with eyes following the pathway of the hands in arm movement, or tilting the head while balancing on other body regions with clearer sensory feedback. Examples might include:

• Balancing on the hands or forearms in a modified Teaser while adding toe taps or subtle head tilts, or simply balancing on the sitting bones while emphasizing upper-body sensory input through the arms, shoulders, and abdominals.
• Lying supine with hips on a squishy ball, legs in a tabletop position arms long on the mat by the sides, just the elbow points down, or arms and fingertips reaching straight up.
• Or simply lifting one leg to the tabletop position at a time. Add a tabletop leg circle to challenge stability and balance. Or change the eye focus in coordination with the movement of the leg.

I may also work with various clients to:

• Use eyes-closed during Footwork on the Reformer to enhance internal awareness
• Incorporate tactile stimulation (e.g., rolling balls under the feet or using textured surfaces)
• Encourage barefoot work with cues such as “rooting,” “suctioning the arches,” or “spreading the toes.” This enhances somatosensory awareness.

These strategies stimulate the sensory system and can be expanded upon by removing visual input or adding rhythm and variability, such as moving to music that simulates the correct quality and tempo of the movement.

Careful observation often reveals which sensory system needs support. For example:

• Clients sensitive to touch may benefit from more distinct tactile input to build proprioception such as, Yamuna domes under feet, and pausing to notice sensations of the breath, or by certain body parts in contact with the mat.
• Those sensitive to sound may benefit from vestibular challenges, including listening to and being guided by the rhythm, volume, and texture of their breathing
• Clients who avoid eye contact or look downward may need structured visual focus tasks, such as intentionally looking in the opposite direction of a movement.

INTEROCEPTION: THE OFTEN-OVERLOOKED DIMENSION

Balance is not only mechanical; it is perceptual, neurological, and behavioral. One of the most powerful contributors to balance is interoception, or the awareness of internal body sensations.

Interoception allows us to perceive our heart rhythm, feel muscular release, and notice our breathing; it also includes awareness of muscular tension, weight distribution, and subtle internal shifts. While simple in concept, interoception plays a profound role in movement quality and nervous system regulation and it’s what Pilates instructors tend to emphasize.

WHY INTEROCEPTION MATTERS

Interoception helps clients:

• Detect asymmetries (e.g., feeling more weight on one side)
• Gauge how much correction is needed
• Recall and recreate a sense of “centeredness.”

This internal awareness also influences the state of the nervous system. When attention is directed inward, it often promotes present-moment focus, calmer breathing, and increased parasympathetic activity, all of which support improved balance.

Just 20–30 minutes of Pilates, practiced more than twice per week, can yield remarkable benefits for individuals with low back pain, according to Mueller and Niederer. This study highlights the impact of regular, consistent practice—echoing Joseph Pilates’ assertion in Return to Life Through Contrology that doing his daily exercises (Pilates Matwork) is key to experiencing the full benefits of his method.

TEACHING INTEROCEPTION IN PRACTICE

Photo credit  jenniferzmuda.com

I use cues that direct attention inward and invite curiosity:

• “Pour your weight into your left foot like sand. Did the left arch change? Are you able to remain vertical? What muscle areas are you feeling? Point to them.”
• “Press your left hand onto your ribs. Lightly place your hand onto the right ribs and breathe into the right side. What did you notice? Exhale fully and repeat taking the hand away from the ribs. Notice any changes.” Usually people are more aware of the expansion of the entire rib area because the sensation of pressure brought their attention to that area. Or they may start breathing more fully because they are looking for a change or sensation to notice. Both are helpful outcomes which may have a greater impact than simply asking a client to “breathe in deeper” or breathe into the right side more.

These can be layered into positions such as side-lying on the arc barrel or integrated into foundational exercises. The goal is not just execution, but awareness.

One client I worked with struggled to coordinate breath with movement. With a background in swimming and strength training, they relied heavily on bracing. (Bracing stiffens all of the abdominal muscles and often involves holding the breath.) Their exhalations and effort to engage were forceful, causing the abdominal wall to expand. My goal for this client was to help them learn how to hollow the abdomen using the deep stabilizers more and reduce the tendency to overuse the obliques. I had noticed that the habitual over engagement of the obliques versus the erector spinae seemed to be contributing to postural imbalances (long kyphosis), neck and shoulder discomfort, and restricted breathing.

The solution was to strip the work back to the breath alone, like using the arc barrel to expand the chest and breathing. Layering in the deep core stabilizers in the dead bug position supine on the reformer with arms in straps grazing the stopper and breathing, and gradually reintroducing full body movement such as the Double Leg Stretch. Over time, as the breath became more balanced (inhale vs. exhale) and less forced, the deeper stabilizers engaged appropriately. Posture improved, pain decreased, and movement became more efficient.

This is interoception in action: developing internal awareness that leads to lasting, functional change.

OPTIMAL VS. MAXIMAL ENGAGEMENT

One of the clearest applications of interoception is the ability to gauge effort.

Rather than maximal contraction, like what my client had been accustomed to doing, effective movement relies on optimal engagement. Research by Aginsky suggests that deep stabilizers function best at approximately 20-30% of maximum voluntary contraction, enough to support movement without restricting breath or mobility. What would happen if the deep core stabilizers provided a reliable foundation for every movement, allowing the superficial muscles to simply execute the specialized actions they were designed to perform?

True stability is the result. While over-engagement creates rigidity and imbalance, true stability allows for real-time adaptability.

In Pilates, this distinction is critical. Whether in Side Leg Lift or Leg Circles, excessive tension limits adaptability and disrupts coordination. Practicing optimal engagement, by contrast, allows movement to remain both stable and dynamic.

When we take the time to train balance, we are not simply strengthening muscles, we are refining perception, enhancing interoceptive awareness, and educating the nervous system. Through sensory integration and diverse movement applications, Pilates becomes not just a physical practice, but a holistic and deeply integrative approach that supports sustainable movement and long-term well-being.

References

Aginsky, K D et al. “Does transversus abdominis function correlate with prone plank and bench bridge holding time in club cricket players?.” South African journal of sports medicine vol. 34,1 v34i1a12984. 1 Jan. 2022, doi:10.17159/2078-516X/2022/v34i1a12984

Assländer, Lorenz, and Robert J Peterka. “Sensory reweighting dynamics in human postural control.” Journal of neurophysiology vol. 111,9 (2014): 1852-64. doi:10.1152/jn.00669.2013

Mueller, Juliane, and Daniel Niederer. “Dose-response-relationship of stabilisation exercises in patients with chronic non-specific low back pain: a systematic review with meta-regression.” Scientific reports vol. 10,1 16921. 9 Oct. 2020, doi:10.1038/s41598-020-73954-9

Pilates, Joseph H., and William John Miller. Return to Life Through Contrology. J.J. Augustin, 1945.