IMMOBILITY IS POISON.
by Jonathon Sullivan MD, PhD, SSC, PBC
Immobility is toxic. It is also a frequently prescribed medical therapy. When is it really indicated?
If movement is medicine, immobility is poison. Immobility leads to sarcopenia, weakness, deconditioning, visceral fat, insulin resistance, obesity, cardiovascular disease, shrinking horizons, disability, isolation, and death. A sessile human being is sending a constant, deadly message to his own body: I’m done with you. You’re not needed. Your body will take your word for it.
So, no hyperbole: Immobility is poison. It is also a frequently prescribed medical therapy.
The use of limb immobilization, postural restriction, bedrest, or very restricted activity is deeply ingrained in the medical mind. I’m old enough to have been trained to tell people with acute lumbar strains to take a couple of days in bed to “just rest,” minimize movement, lift no more ten pounds, and so on. This was a prescription for poison, as often as not made worse with a prescription for opioids. We didn’t know any better. But I for one am really, really sorry.
Limb immobilization is part and parcel of modern orthopedic practice, and for good reason. This is critical to understand before we go on: sometime immobility is absolutely necessary, just as drugs, which always have some toxicity, can be lifesaving. In the orthopedic case, optimal healing of broken bones requires good approximation of bone segments with limited movement, or malunion can occur. That word means pretty much what you think it means. It’s not good. And so at the same time I learned to tell back pain patients to go to bed, I learned how to put on all manner of casts and splints. I also learned that these can be treacherous interventions. Circumferential casts—which wrap around the entire limb with plaster or other stiff material—can cut off circulation, resulting in pain, muscle damage, kidney injury, and even loss of limb or life. I was a confirmed splint-er for most of my career, and avoided circumferential casts whenever possible.
Patients who are profoundly ill or injured cannot tolerate taxing physical activity, and are relatively immobile by default. Nobody thinks a patient with septic shock, acute myocardial infarction, or multiple trauma needs a workout just now. Immobilization of the severely ill, the recently surgerized, and acutely injured bones and other structures makes sense in the short term. Even in minor illness and injury, there’s a lot to be said for a day or three of rest and a good night’s sleep. So I'll have no patience for those who straw-man what I'm saying here.
But doctors can take immobilization too far, and frequently do. I have clients who have been injured by doctor-prescribed immobility. I have a gifted and very strong lifter who was immobilized in the prone (face-down) position for weeks after retinal surgery, and she’s been struggling with the results of her prolonged immobility ever since. We are making progress again, but the effect on her strength, mobility, and well-being has been very real. I have several lifters who have sustained minor lower-extremity fractures that did not involve the weight-bearing axis and did not require casting or surgery, but were placed in immobilizing splints. They have subsequently seen limitations in their mobility and increases in chronic pain that we are finally starting to conquer, but only after long and difficult work.
And while it may not count as immobility or even postural restriction, we have more than enough experience with clients being told after joint replacement to limit their activity and loading. Joint replacement surgeons often seem more concerned about protecting their precious prosthesis than the bone stock surrounding it or the function it was supposed to restore, and impose crazy restrictions on patients, when there is no good evidence to actually support such restrictions.
In fact, the scientific literature on immobility in medicine is shockingly limited, and most of it is focused more on dealing with or preventing the complications of immobility rather than the actual benefit of immobility itself. In the setting of acute severe injury or illness, long-bone and other critical or unstable fractures at risk of nonunion, or chronic conditions characterized by extreme frailty and exercise intolerance, human studies of immobility are ethically and practically difficult, but that’s not what I’m talking about here.
Consider the practice of prolonged immobilization of patients in the supine position after macular (retinal hole) surgery. We do not have a conclusive body of data demonstrating that this serves any purpose. Take a look at the plain-language summary of a Cochrane meta-analysis on this question:
Following surgery for macular hole, a period of face‐down positioning for up to two weeks may be advised, with the aim of improving the likelihood of success by maintaining contact of the gas meniscus with the macula. However, face‐down positioning is of unproven benefit, uncomfortable and associated with adverse events including ulnar nerve injury.
We conducted a systematic review of outcomes for individuals with idiopathic macular holes following postoperative face‐down positioning. We found three randomised controlled trials (RCTs). Two of the three trials suggested a benefit in holes larger than 400 microns in diameter. None demonstrated evidence of a benefit in smaller holes.
A meta-analysis by Tatham et al came to similar conclusions.
Similarly, the use of immobilization (“bed rest”) in acute mechanical back pain is now recognized (see here, here, and here) as contraindicated—and yet it is still often prescribed.
For acute orthopedic injuries, a more judicious, case-by-case approach is warranted. Immobilization is not to be undertaken lightly, because the trade-off between fracture healing and the complications of immobility are very real, but sometimes clearly indicated. Many fractures require immobilization of the fracture fragments and the proximal and distal joints (the joint above and the joint below) to insure approximation and healing of the fracture fragments and to prevent damage to associated nerve and vascular structures. But many fractures do not. For example, humeral (upper arm) fractures are often treated with just a sling. Mid-shaft fibular fractures (the little chicken bone on the outside of your leg) that do not involve ankle or knee joint can be treated with early mobility—no cast required, but often prescribed, to the patient’s detriment.
As for other, non-fracture musculoskeletal injuries: immobility is almost always contraindicated. The injury may very well require a brief period of rest and support (wraps and straps), deloading, decreased volume, and good-old-fashioned pampering.
But movement is medicine for most sprains, strains, twists, and tweaks. Your back is out? Move it. Your shoulder is a bit tweaky? Move it. You have a torn hamstring? Do a Starr protocol, or, if your coach or physiotherapist prefers, a protocol of high-intensity, very low-volume work. We don’t have dispositive evidence either way. But move.
The take-home should be clear by now. If you’re sore, if you have arthritis, if you have a sprain or a strain…move it. If you have a bony injury, surgery, or illness, and your doctor prescribes immobility, ask questions. Is this really needed? Is there good data on this? What are the potential complications of this immobility? Is there an option for early movement? How can I train or at least move around this restriction?
Don’t be shy. That doctor works for you. He gets paid, in part, to answer your questions.
And for the doctors reading this: you ask questions, too. Are you prescribing or imposing immobilization or postural restriction too liberally? Where is the evidence? What is the number-needed-to-treat and the number-needed to harm? Do we even know, or is the prescription of immobility or postural restriction merely longstanding clinical practice?
The great medieval physician Paracelsus said “The Dose is the Poison.” What he meant was that a therapeutic could heal or harm, depending on the dose. Sometimes rest and immobility are necessary for recovery.
But quite often the real indication is for movement, and in such cases restriction of movement becomes a poison rather than a medicine. Doctors need to be more circumspect about it, and patients need to be more inquisitive about it. That means you.
Jonathon Sullivan MD, PhD, SSC, PBC is a retired emergency physician and research physiologist, and the owner and head coach of the Greysteel Strength and Conditioning Clinic in Farmington Hills, Michigan, which specializes in training adults over 50. He is the author of The Barbell Prescription: Strength Training for Life After Forty, with Coach Andy Baker.