by Jonathon Sullivan MD, PhD, SSC, PBC
Bone loss is one of the horrors of growing older. But we have an effective medicine for prevention, management, and reversal: The Barbell Prescription.
Be sure to check out the video review of the Hong and Kim paper at the end of this article.
One of the key features of aging, and particularly unhealthy aging, is the loss of bone mineral density, or osteopenia, which can progress to the very serious condition called osteoporosis. These conditions are endemic in the elderly population, they are part of the frailty syndrome of aging, and they place us at high risk for fractures. This includes both post-traumatic fractures and pathological fractures, which are from bones failing in the setting of low force physical activities that would never damage bones in other populations. Bone mineral loss is more common in women, but it affects men too, and strikes up to 70% of people by the time they're in their 80s. Up to 200 million people suffer from osteoporosis, far more from osteopenia, and osteoporosis results in about 3 million fractures a year worldwide. This corresponds to an unfathomable amount of human suffering, morbidity, and mortality, not to mention astronomical costs to economies and healthcare systems. So bone loss is one of the horrors of growing older. But we have an effective medicine for prevention, management, and reversal: resistance exercise, also known as strength training. At Greysteel, we’ve seen clients who’ve reversed their osteoporosis to the point where their bone mineral density no longer meets diagnostic criteria and they no longer have the disease. There’s usually a fair amount of whooping and hollering and happy dancing when that happens. But don’t take my anecdotes for it. Check out the fairly recent paper in the journal Endocrinology and Metabolism, 2018, by Hong and Kim. It’s a narrative review of what’s known about this topic, and it’s must reading for anybody interested in bone health...which means everybody over 50, and everybody who loves somebody over 50. As the authors point out, we know that mechanical loading and exercise improve bone mass and bone mineral density. The question is, how do we prescribe and dose exercise medicine optimally? The authors make the case, based on clinical and basic science data, that the answer is resistance training. Other forms of exercise like walking, swimming, aerobics, and tai chi are certainly very good for you, hitting various parameters of fitness, especially cardiovascular fitness. But bone density and bone mass are dependent on bone remodeling, and for that you need an adequate stimulus, meaning a significant magnitude of training stress. The authors cite limited data—because sadly all this data is limited—that walking and aerobics and swimming just don’t deliver the stress needed for bones to respond with increased mass, density and favorable remodeling. This is something I’ve been saying for years, and I said it in our book, The Barbell Prescription. You need to load those bones with weight—safely, rationally, progressively—if you want to get that osteogenic response. Moreover, the response of bone is highly specific. So if you do seated curls or bench presses or laying knee extensions, you’ll get bony responses where the trained muscles attach, and that’s good. But the real morbidity in elderly populations is from traumatic or pathologic fractures of the spine, like vertebral compression fractures, and the hip, like intertrochanteric fractures. These injuries transform human lives, and not for the better. So the prescription has to be not just for strength training, but for structural strength training exercises, exercises that load the axial skeleton and the hips. And that means loading of standing compound movements. And you know what that means: squats, deadlifts, overhead presses, standing curls, and the like. It means a barbell prescription. Other great points in this paper: The greatest benefits are observed when the program is progressive, increasing load over time. That means training, not just exercise, it means programming, it means a Barbell Prescription, it means the Athlete of Aging. As the authors point out, It also means proper nutrition and recovery. The authors talk about what’s known about the cellular responses and signaling systems that transduce loading into a biological response--you know, for the nerds. Not necessary for us to talk about right now (or ever, as far as most of you are concerned). But along the way they make the crucial observation that it’s not just bone mineral density and bone mass that are important. The quality of the bone is also critical. Bone mass and density are important for bone strength, to be sure. But the microstructure of the bone is equally important. Bone remodels not just density and mass, but it also realigns its microgeometry, or histology. If you look closely at bone, especially under a microscope, you see that bone models its histology to best accommodate the forces to which it’s adapting—laying down arches and girders and buttresses that allow the bone to bear the loads it’s seeing every day, in the home and in the gym.
Left: Photograph of the inner surface of a bone showing the fine trabecular structure. From Daniel Ullrich Threedots; CC license. Right: Normal and pathological trabecular bone structures. From Laboratoires Servier, CC license.
Here's the punch line: The authors point out that microstructure and other intrinsic bone quality parameters are not characterized by DEXA, dual emission x-ray absorption, which is the most common clinical and research assay for the response of bone health to an intervention. This means that even though the literature makes clear that resistance training is good for your bones--in fact, it's essential--the research and clinical experience may actually be underestimating the benefit, because the assay doesn’t tell us about micro-modelling and other factors. So this is a terrific little review on a damn important topic. But here’s the best part. This little paper is open access, so you can download and print it for yourself, your loved ones, your doctor. It’s a bit nerdy in parts, sure, but except for the section on signal transduction it’s totally accessible to the layman reader; very readable. Download a copy and send it to your mom or your grandma. And her doctor. When people over 50 use a program like the ones we lay out The Barbell Prescription, they’re not just getting stronger and bigger muscles, better cardiovascular and metabolic health, more mobility, and better balance. They’re getting stronger bones, which means they’re harder to break, and staving off some of the most horrific catastrophes that can befall an aging adult—vertebral compression fractures, hip fractures,and pathologic fractures. So please, go and get a copy for your loved ones, and maybe a copy of this too.
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.
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