Today, babies born in the United States can expect to live more than 79 years, nearly eight years longer than the average just 50 years ago. Yet while the typical lifespan has risen, healthy life expectancy — the number of years a person can live in full health — hasn’t kept pace. In fact, the typical American “healthspan” has declined since the start of the 21st century.

In other words, we’re outliving previous generations — but spending more of those years managing pain, disability, and chronic disease. That reality underscores what conversations about life expectancy often miss: it’s not enough for our healthcare system to help people live longer. We must also ensure they can remain healthy as they age.

The growing gap between lifespans and healthspans is a global phenomenon, but it’s particularly stark in the United States. A recent study estimated that the typical U.S. healthspan is 12.4 years shorter than the typical lifespan, meaning Americans can expect to spend more than 12 years of their lives grappling with chronic disease. That’s nearly three years more than the global average. 

As lifespans have increased, this stretch of ill health has only gotten longer: in 2000, the difference between the typical U.S. lifespan and healthspan was less than 11 years.

What’s driving this troubling trend? The largest contributor is musculoskeletal conditions — disorders affecting bones, muscles, and joints — which become especially common in the later years of life and are the leading cause of disability worldwide.

In the United States, these conditions affect one in three people, eroding their independence and quality of life — while costing us over $380 billion annually.

Consider osteoarthritis, which afflicts roughly 33 million Americans by gradually wearing down cartilage in the joints. It causes pain, swelling, and mobility-limiting stiffness. 

Or take lower back pain, which affects roughly eight in 10 Americans at some point in their lives and can become debilitating if left unaddressed.

Musculoskeletal conditions like these typically aren’t reversible — but they are largely preventable and almost always better managed when recognized early. This can be challenging since the warning signs can be subtle and therefore easy to dismiss. 

Extending our healthspans will require changing the way we think about musculoskeletal care: not just as treatment after something has gone wrong, but at the moment signs develop, as a way to protect function, independence, and quality of life before limitations emerge. And it must involve care and exercise strategies, like regularly engaging in low-impact exercises and strength training, that reduce the risk of these conditions developing and slow their progression when they do.

Several programs already support proactive maintenance in populations at risk of injury. The Aspen Institute’s Project Play helps young athletes to avoid injuries such as ACL tears. A California Kaiser Permanente initiative cut hip fracture rates roughly in half by providing at-risk seniors with personalized preventive care plans.

Technological advances are making targeted prevention even more effective. AI-enabled analyses can help clinicians detect posture or gait problems, and recommend interventions before the issue escalates. For seniors with chronic knee pain, correcting these issues dramatically reduces the likelihood of requiring knee replacement.

Movement data can also inform personalized exercise and therapy regimens to help people preserve mobility. Research has shown that, for some conditions, physical therapy is just as effective as surgical repair. 

Large companies like Google and Microsoft have worked to protect employees from musculoskeletal injury with on-site amenities such as standing desks and gyms that encourage movement throughout the day. 

Universities like Stanford and the University of Rochester offer a range of resources, from group classes to preventive screening, to reduce the risk of musculoskeletal pain and injury.

But patients shouldn’t have to rely on specialized research programs or perks to access the cutting edge of musculoskeletal health. The Hospital for Special Surgery (HSS) and Peloton are each working to make musculoskeletal wellness intentional, accessible, and routine.

HSS is advancing musculoskeletal wellness through a new institute for movement and longevity, alongside initiatives to expand virtual physical therapy and advance research to reduce the risk of osteoarthritis after injury. Peloton IQ — an AI-powered overlay to Peloton’s instructor-led fitness programs — encourages members to take a more holistic approach to health by complementing regular cardio exercise with strength training, Pilates, yoga, stretching, and more.

HSS and Peloton are also collaborating to develop virtual classes on injury prevention and care with Peloton instructors directed by leading HSS doctors and clinicians.

As a society, we must rethink what “successful” aging means. For too long, the focus has been on adding years to life. Those years mean far less if they’re marked by pain, immobility, and lost independence.

By prioritizing healthspan, we can redefine what it means to grow old — and ensure that the time we’re adding can be lived to the fullest.

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