Gait Speed and Dysmobility - a Vital Sign or Sign of Vitality?

This week, I welcome as co-authors three colleagues and dear friends who have worked with me on all 4 editions of the American College of Sports Medicine's textbook - ACSM's Exercise Management for Persons with Chronic Disease and Disabilities (aka CDD1-CDD4).

Patricia L. Painter - my first scientific colleague, whom I met in 1988 after I presented an abstract on exercise in patients with renal failure, after which we became great friends and Trish became the top world authority on exercise in kidney disease;

Elizabeth J. Protas - Vice President and Dean of the School of Health Professions at the University of Texas Medical Branch, Betty is a physical therapist and kindred spirit that I met in 1994 and who has worked on all 4 editions of CDD;

J. Larry Durstine - Chair of Exercise Science at the University of South Carolina and a past President of the American College of Sports Medicine, Larry’s wife Linda has spent many months (in aggregate) waiting for Larry as well as hosting me in her home while we spent his “free time” working on CDD1-CDD4.


In a recent brief report in JAMA, Cummings, et al., draw attention to the need to assess mobility in patients over 65 years of age and call for use of 4 meter gait speed as a new “vital sign” (1). We applaud their contributions on gait speed as a key clinical parameter, admiring their leadership in raising this issue. Leaders from the American College of Sports Medicine have been calling for an exercise vital sign (or physical activity vital sign) for some time (2).

Cummings, et al., are essentially raising the notion that gait speed is a nuanced form of an exercise vital sign, one that focuses more on mobility than on physical activity. While walking at any speed is a form of physical activity, walking with alacrity (i.e., good gait speed) is a sign of vitality. The key point is that both measures – low mobility (not being active by choice) and dysmobility (physically struggling to be active) – are associated with high risk of chronic disease, institutionalization and mortality.

But gait speed alone does not go far enough to characterize dysmobility, as additional issues of physical functioning are also of great concern. That’s because most people greatly fear loss of independence, and several aspects of physical functioning beyond gait speed can lead to the need for assistance and inability to live in one’s own residence. These threats to quality-of-life include the inability to:

• Do sustained walking,

• Arise from a seated position (sit-to-stand),

• Ascend/descend steps,

• Manipulate objects of modest mass (<5 kg), and

• Extend core musculature through a range-of-motion (bend at the waist and hips).

Chronological age is often irrelevant, as many patients with a chronic disease have alarmingly low levels of physical functioning by these measures, yet are well below the age of 65.

In drafting the forthcoming 4th edition of the American College of Sports Medicine’s textbook, Exercise Management for Persons with Chronic Diseases and Disabilities (link goes to CDD3; CDD4 is in press) (3), we concluded that the current evidence base on physical functioning is so incomplete that we chose to base our recommendations on evidence-informed expert opinion, rather than limit recommendations to current knowledge. Thus, in addition the exercise vital sign as a measure of physical activity, CDD4 will recommend important additional measures that reflect the other key aspects of physical functioning and contribute to independent living.

We asked:

“What is the minimum physical functioning for which a clinician should start to become alarmed when a patient can’t complete them”?

At what point should a provider become concerned about the safety and security of an individual, either in response to an emergency such as a fire, or just in their ability to sustain themselves? In our opinion, the following performance measures should be considered as an expected minimum absolute ability level for any adult, independent of age or burden of chronic conditions:

• 6 or 8 m gait speed > 0.6 m/s,

• 8 sit-to-stand repetitions in 30 seconds,

• 8 arm curls with a 4 kg mass,

Ascend a flight of 10 steps in <30 seconds, and

Chair sit-and-reach to their toes on both sides.

Anyone who cannot muster enough ability to complete all 5 tasks is sufficiently debilitated to raise concern. These minimum standards are set high because loss of independence is perhaps the most feared of all health outcomes, along with losing one’s mental faculties and becoming a burden on one’s children.

Our recommendations are surely flawed. For example, the 6 minute walk test is much more well-suited to be an estimate of a person’s ability to do sustained walking, such as is required to grocery shop for one’s own self. Our shopper must also carry the groceries at least part of the way home, and up any steps to his or her abode. But many health clinics don't have the space to do 6 minute walk tests, and we concluded that it’s more important to recommend something they can do than to make an ivory-tower recommendation. Similarly, stair climb research studies have varied from 9 to 12 steps, the exact number most likely being what's in the stairwells at the investigator's facility! Common sense would be to pick a number - we picked 10 - and go with it as a basic guide. Similarly, the number of arm curls or weight being used, or the number of sit-to-stand exercises are not proven or standardized for all conditions. But only being able to do 1 or 2 is surely alarming. Is 3 or 4 alarming? Less so, but yes. At what point is it not alarming? We chose 8 reps.

We hope to err on the side of making a useful recommendation, risking being inaccurate, rather than to make no recommendation because of either insufficient or incoherent evidence. At some point, clinicians must use their common sense in order to artfully improvise a recommendation for the patient - a FACT that anyone who’s worked in a clinic realizes. In this perspective, strict adherence to “evidence-based medicine” is woefully inadequate - patient's need providers to advise something that is informed.


What Should Providers DO About Dysmobility?

Even more important, merely obtaining and documenting these measures cannot be the endpoint. Once one knows that a patient has dysmobility, one has a moral imperative to provide interventions to treat and improve dysmobility and low physical functioning!! If your Mom were low on any of these tests and she asked for your advice, would you tell her you just don't know how to provide an outcome she'll value?

Being low on any of these measures is an indication for referral to a clinical exercise training program. But in the USA, that’s not happening today. Most people feel they can’t afford to pay for a supervised group exercise program overseen by an exercise professional (such as a clinical exercise physiologist, physical therapist or occupational therapist), and such services are rarely covered by health plans. So the vast majority of people who need help go without, while the Bipartisan Policy Center, in Washington, D.C., warns that cardiometabolic disease threatens America's economic future and that America is insufficiently prepared for long-term care needs. Providers can carefully craft a diagnosis so that the patient can be referred to individual treatment as a covered benefit, such as physical or occupational therapy, but what most patients really need is a clinically-supervised all-around program that enhances social interaction around exercise and that prevents dysmobility.


What's Next?

We applaud Cummings, et al., and JAMA for drawing vitality to attention, but we humbly suggest that measuring gait speed alone doesn’t go far enough. More research is needed to evaluate and clarify what the minimum absolute abilities of physical functioning should be, and we need more innovations to implement clinical programs that maintain mobility and independence. But, for now, we think the above recommendations should be regarded as a minimum acceptable level of mobility. Moreover, no provider should see dysmobility below these levels of physical functioning and have to stand idly-by as their patient drifts closer to the nursing home. Clinically-supervised exercise programs and the professionals who can provide the services must become a compensated piece of our health care system.

Geoffrey E. Moore, MD FACSM
Sustainable Health Systems

Patricia L. Painter, PhD FASCM
University of Utah

Elizabeth Protas, PT, PhD, FACSM
University of Texas, Medical Branch

J. Larry Durstine, PhD, FACSM
University of South Carolina



1) Cummings SR, Studenski S, Ferrucci L. A Diagnosis of Dismobility—Giving Mobility Clinical Visibility: A Mobility Working Group Recommendation. JAMA. 2014;311(20):2061-2062. doi:10.1001/jama.2014.3033.

2) Joy EL, Blair SN, McBride P, Sallis RE. Physical activity counseling in sports medicine: a call to action. Br J Sports Med 2013; 47:49–53.

3) Haskell WL, Lee IM, Pate RR, Powell KE, Blair SN, Franklin BA, Macera CA, Heath GW, Thompson PD, Bauman A. Physical activity and public health: updated recommendation for adults from the American College of Sports Medicine and the American Heart Association. Circulation 2007;116:1081-1093; originally published online August 1, 2007. Available online doi: 10.1161/CIRCULATIONAHA.107.185649

4) Moore GE, Durstine JL, Painter PL, eds. ACSM’s Exercise Management for Persons with Chronic Diseases and Disabilities, 4th edition. American College of Sports Medicine / Human Kinetics, Urbana, IL (in press).

5) Sawatzky R, Liu-Ambrose T, Miller WC, Marra CA. Physical activity as a mediator of the impact of chronic conditions on quality of life in older adults. Health Qual. Life Outcomes. 5:68, 2007.

6) Jones CJ, Rikli RE, Max J, Noffal G. The Reliability and Validity of a Chair Sit-and-Reach Test as a Measure of Hamstring Flexibility in Older Adults. Res Quarterly Exerc Sport. 1998; 69(4), 338-343. LL.