Essential Points:

• Ian Waterman’s Extraordinary Adaptation: After losing his sense of proprioception due to a rare neurological condition, Ian had to consciously relearn how to move, relying entirely on vision to control his body. His story showcases the brain’s incredible ability to adapt and rewire itself.

• The Vital Role of Proprioception: Proprioception, often called the “sixth sense,” allows us to move effortlessly without thinking. It integrates with the vestibular and visual systems to maintain balance, coordination, and spatial awareness, highlighting how crucial it is for daily function and fall prevention.

• Training and Protecting Proprioception: Unlike Ian, most people can train and maintain proprioception through balance exercises, barefoot training, and dynamic movement. Strengthening this system is essential for reducing injury risk, improving coordination, and maintaining independence as we age.

Imagine waking up one morning and realizing that you’ve lost all feeling in your body. Not just numbness, but something far more unsettling, you can’t tell where your arms and legs are unless you look at them. You can’t even feel your grasp as you grab your own hands. If you close your eyes, it feels as though your body has vanished and you are simply floating in space

This was Ian Waterman’s reality in 1971, at the young age of 19. A sudden illness attacked his nervous system, robbing him of proprioception, the sense that allows you to know where your body is in space, and his feeling of touch. He could still feel pain, temperature, and texture, but the automatic awareness of his limbs was gone.

The simplest movements such as standing up, reaching for an object, and even walking became impossible. Without proprioception, Ian had no way to coordinate his body without watching every motion, as if he were a marionette with cut strings. Doctors were baffled with no idea of his diagnosis, and at first, it seemed like he would never walk again.

Most of us take movement for granted. You don’t have to think about lifting a fork to your mouth, stepping off a curb, or scratching your head. But Ian’s condition exposed just how much we rely on an invisible system working behind the scenes. So, what exactly is proprioception, and why is it so vital to everyday life?

What Is Proprioception?

You might not think about it often, but proprioception is the reason you can touch your nose with your eyes closed, walk across a dark room without stumbling, or balance on one foot without constantly adjusting.

Proprioception is your body's ability to sense its position, movement, and force without looking. It’s often called the "sixth sense" because it operates beneath conscious awareness, allowing for seamless movement. Specialized nerve receptors in your muscles, tendons, and joints send constant feedback to your brain about your body's position. This lets you adjust on the fly, whether you’re catching a ball, navigating a staircase, or even just typing on a keyboard.

Your ability to balance and move smoothly depends on three key systems working together:

• Vestibular system (inner ear): Detects head position and movement, crucial for spatial orientation and balance.

• Visual system (eyes): Helps orient you to your surroundings.

• Somatosensory system (proprioception & touch): Provides internal feedback about limb positioning, movement, and what the body feels.

If one of these systems is compromised, the others can usually compensate. But losing proprioception completely? That’s something even the most skilled neurologists has never seen. And for Ian, it meant he had to rebuild his entire way of moving from scratch with no known inspirational stories to guide him.

Ian’s Struggle and Triumph (1)

In 1971, at just the age of 19, Ian Waterman contracted an infection that changed his life forever. No one knows exactly where this infection came from, but it’s suspected it was from a small cut he received while working as a butcher. This infection ravaged his sensory nerves and lead to him essentially being paralyzed for all intents and purposes.

When Ian was first hospitalized, the outlook was bleak to say the least. Doctors had no cure, no clear treatment, and little hope that he would regain independent movement. In fact, they didn’t even really know what was wrong with him, there was no diagnosis. His limbs were intact, his muscles undamaged, but without proprioceptive feedback, they were useless.

At first, he was unable to move at all. Without proprioception, even sitting upright was a challenge because his body had no sense of equilibrium. He tried, and tried, and tried to simply sit-up in bed with no success. Walking was completely out of the question. If he wasn’t looking at his feet, he had no idea where they were.

But Ian refused to accept a life of immobility, he was too young. If his body could no longer operate automatically, he decided he would take full conscious control of it. He would force himself to move again through sheer will and effort.

With painstaking daily work, he learned to move again, relying entirely on his vision to guide him. Every step had to be deliberately choreographed. He would stare at his feet while walking, visually confirming each movement before taking another. If the lights went out, or if someone suddenly spoke to him and broke his focus, he could collapse. He had to be an athlete at the height of his physical game every step of the way to simply take a step.

His training was grueling. He practiced standing, then shifting his weight, then taking small steps. His brain had to rewire itself, using vision and mental concentration to compensate for what his body could no longer sense.

Against all odds, Ian regained the ability to walk, work, and live independently. But even decades later, he still can’t move without looking. If he closes his eyes, his body becomes a ghost. If the lights go out, he is trapped in space with every move practically guaranteeing a fall.

Ian’s story is a testament to human adaptability and the brain’s incredible plasticity. But it also raises an important question: If we take proprioception for granted, how can we protect and train it before we even realize we need it?

The Science Behind His Condition

What happened to Ian Waterman wasn’t just unusual, it was almost unheard of. His condition, later labelled and known as sensory neuronopathy (or sensory ganglionopathy), is an extremely rare neurological disorder that damages the sensory nerves responsible for sensations such as proprioception. (2, 3) Unlike most nerve-related conditions that affect movement through muscle weakness or paralysis, Ian’s muscles were perfectly fine, he just had no way of controlling them without visual feedback.

Sensory neuronopathy is believed to be caused by an autoimmune response, where the body's own immune system mistakenly attacks the sensory nerves. (2, 3) In Ian’s case, the condition struck suddenly, leaving him without proprioceptive input below his neck. His nerves could still carry signals related to pain, temperature, and texture, but the deeper awareness of limb position, the sense that allows movement to feel natural and automatic, was gone.

Cases like Ian’s are incredibly rare, but they’ve provided scientists with critical insights into how movement, motor control, and sensory feedback are connected. Before his case, proprioception wasn’t widely discussed outside of specialized neurology circles. Now, it’s recognized as a crucial part of human movement, affecting everything from athletic performance to fall prevention in older adults.

Researchers studying Ian’s adaptation learned a valuable lesson, the brain is remarkably plastic. It can rewire itself in response to sensory loss, allowing other systems, like vision and conscious control, to take over. But this adaptation comes at a cost. Ian had to train his brain and body relentlessly to regain function, and even now, decades later, he has to concentrate on every movement to stay upright. His effortless looking movements are anything but that.

His case also highlights an important reality, most of us don’t think about proprioception until something goes wrong. But what if we could train and strengthen it before problems arise?

Lessons from Ian’s Story

Ian’s struggle to regain movement offers an important reminder: proprioception isn’t just for athletes or those recovering from neurological disorders, it’s something everyone relies on, especially as we age. Our ability to effortlessly move is a gift we should all cherish.

For most people, proprioception quietly works in the background, adjusting and fine-tuning movements without conscious effort. But like any other system in the body, it can weaken over time, particularly if it’s not actively engaged. Aging, injury, and even a sedentary lifestyle can degrade proprioception, increasing the risk of falls, joint instability, and loss of coordination. (4, 5, 6, 7, 8, 9)

The good news? Proprioception can be trained and maintained, just like strength or endurance, for the majority of us. (10, 11) Unfortunately, due to the nature of Ian’s disease, this is not quite true for him.

How to Improve and Maintain Proprioception

If Ian was able to regain movement without proprioceptive input, imagine what you can do with a fully functioning system. Here are some ways to train and enhance proprioception:

• Balance Exercises: Standing on one leg, walking heel-to-toe, or using a balance board can challenge and strengthen proprioceptive feedback.

• Eyes-Closed Training: Try simple movements like touching your nose, standing on one foot, or walking in place with your eyes closed. This forces your body to rely on internal sensory feedback rather than visual cues.

• Barefoot Training: Walking barefoot, especially on uneven surfaces like grass or sand, enhances sensory input from your feet, improving proprioception. In fact, I suggest training your feet and altering your footwear as a first line for improved balance and long term functional health. Learn more about the feet in this three-part article series here.

• Dynamic Movements: Exercises that challenge coordination, like agility drills, yoga, or tai chi, help train your body to adapt to different positions and movements.

• Strength and Stability Work: Strengthening the muscles around joints, particularly the ankles, knees, and hips, supports proprioceptive function and reduces injury risk. Learn more about strengthening the muscles of balance here.

Even small changes, like standing on one foot while brushing your teeth, can help keep your proprioceptive system sharp. And for older adults, regular proprioception training can significantly reduce the risk of falls, making it a critical part of long-term health and independence.

Final Thoughts: Never Surrender to Illness

Ian Waterman’s story is both remarkable and humbling. It reminds us just how complex and fragile human movement is, and how easily we take it for granted. Yet, it also shows us how remarkably resilient we can be as humans.

His experience highlights the incredible resilience of the brain and body. With enough determination, adaptation is possible, even in the face of extreme loss. But perhaps the greatest lesson from his journey is this:

We often don’t realize the importance of something until it’s gone.

Most people will never experience total proprioceptive loss like Ian did. But that doesn’t mean we should ignore this vital system. The loss of balance as a whole, due to deconditioning, is by and large extremely common as we age. By understanding proprioception and actively training it, you can safeguard your ability to move smoothly, confidently, and safely for years to come.

So take a moment today to appreciate your body’s ability to move without effort. Try standing on one foot, closing your eyes, or walking barefoot on different surfaces. The more you challenge your proprioception now, the better it will serve you in the future.

If you want to learn more about Ian’s incredible journey be sure to check out this documentary, The Man Who Lost His Body or the book Pride and a Daily Marathon. And remember, if Ian’s story teaches us anything, it’s that movement is never something to take for granted.

References

1. British Broadcasting Company. The man who lost his body. Top Documentary Films. Published online 1988. Accessed February 9, 2025. https://topdocumentaryfilms.com/the-man-who-lost-his-body/

2. Gwathmey KG. Sensory neuronopathies. Muscle & Nerve. 2015;53(1):8-19. doi:10.1002/mus.24943

3. Amato AA, Ropper AH. Sensory ganglionopathy. New England Journal of Medicine. 2020;383(17):1657-1662. doi:10.1056/nejmra2023935

4. Proske U, Gandevia SC. The proprioceptive senses: their roles in signaling body shape, body position and movement, and muscle force. Physiological Reviews. 2012;92(4):1651-1697. doi:10.1152/physrev.00048.2011

5. Ferlinc A, Fabiani E, Velnar T, Gradisnik L. The Importance and Role of Proprioception in the Elderly: a Short Review. Materia Socio Medica. 2019;31(3):219. doi:10.5455/msm.2019.31.219-221

6. Teramoto W. Age-related changes in visuo-proprioceptive processing in perceived body position. Scientific Reports. 2022;12(1). doi:10.1038/s41598-022-12022-w

7. Adamo DE, Alexander NB, Brown SH. The influence of age and physical activity on upper limb proprioceptive ability. Journal of Aging and Physical Activity. 2009;17(3):272-293. doi:10.1123/japa.17.3.272

8. Liu Y, Dong S, Wang Q, Liu Z, Song Q, Shen P. Deficits in proprioception and strength may contribute to the impaired postural stability among individuals with functional ankle instability. Frontiers in Physiology. 2024;15. doi:10.3389/fphys.2024.1342636

9. Findlater SE, Hawe RL, Semrau JA, et al. Lesion locations associated with persistent proprioceptive impairment in the upper limbs after stroke. NeuroImage Clinical. 2018;20:955-971. doi:10.1016/j.nicl.2018.10.003

10. Aman JE, Elangovan N, Yeh IL, Konczak J. The effectiveness of proprioceptive training for improving motor function: a systematic review. Frontiers in Human Neuroscience. 2015;8. doi:10.3389/fnhum.2014.01075

11. Yılmaz O, Soylu Y, Erkmen N, Kaplan T, Batalik L. Effects of proprioceptive training on sports performance: a systematic review. BMC Sports Science Medicine and Rehabilitation. 2024;16(1). doi:10.1186/s13102-024-00936-z