Leisure Time Physical Activity Among U.S. Adults With Arthritis, 2008−2015

  • Louise B. Murphy
    Correspondence
    Address correspondence to: Louise B. Murphy, PhD, Arthritis Program, Division of Population Health, Centers for Disease Control and Prevention, 4770 Buford Highway NE, Mailstop F-78, Atlanta GA 30341
    Affiliations
    Arthritis Program, Division of Population Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia
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  • Jennifer M. Hootman
    Affiliations
    Arthritis Program, Division of Population Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia
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  • Michael A. Boring
    Affiliations
    Cutting Edge Technologies and Solutions, Mesa, Arizona
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  • Susan A. Carlson
    Affiliations
    Physical Activity and Health Branch, Division of Nutrition, Physical Activity, and Obesity, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia
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  • Jin Qin
    Affiliations
    Epidemiology and Applied Research Branch, Division of Cancer Prevention and Control, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia
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  • Kamil E. Barbour
    Affiliations
    Arthritis Program, Division of Population Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia
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  • Teresa J. Brady
    Affiliations
    Arthritis Program, Division of Population Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia
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  • Charles G. Helmick
    Affiliations
    Arthritis Program, Division of Population Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia
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      Introduction

      In 2016, leisure time physical activity among U.S. adults aged ≥18 years with and without arthritis was studied to provide estimates using contemporary guidelines (2008 Physical Activity Guidelines for Americans) and population-based data (U.S. National Health Interview Survey).

      Methods

      Estimated prevalence of: (1) meeting aerobic, muscle strengthening, and both aerobic and muscle strengthening guidelines, by arthritis status, from 2008 to 2015; and (2) meeting guidelines across selected sociodemographic characteristics and health status and behaviors, among adults with arthritis, in 2015.

      Results

      In 2015, 36.2%, 17.9%, and 13.7% of adults with arthritis met aerobic, muscle strengthening, and both guidelines, respectively; age-standardized prevalence of meeting each guideline was significantly lower among those with arthritis versus those without (e.g., 41.9% [95% CI=39.5%, 44.3%] and 52.2% [95% CI=51.2%, 53.2%] met the aerobic guideline, respectively; p<0.001). From 2008 to 2015, meeting aerobic guideline rose modestly (3 percentage points) among those with arthritis compared with larger gains (7 percentage points) among those without arthritis; the percentage of adults with arthritis meeting muscle strengthening and both guidelines remained the same in contrast to modest (statistically significant) increases among those without arthritis. Among adults with arthritis, age-standardized percentage meeting each guideline was highest among those with at least a university degree.

      Conclusions

      Percentage meeting each guideline was persistently low among adults with arthritis. The lower prevalence among adults with arthritis versus those without suggests that adults with arthritis need additional strategies to address potential barriers (e.g., pain, psychological distress, inadequate medical support) to physical activity.

      Introduction

      Regular physical activity can improve the health of people living with chronic disease and is a recommended non-pharmacologic intervention for many chronic conditions, including arthritis.
      U.S. DHHS
      2008 Physical Activity Guidelines for Americans.

      Physical Activity Guidelines Advisory Committee. Physical Activity Guidelines Advisory Committee Report, 2008. http://health.gov/paguidelines/report/. Accessed May 26, 2016.

      For people with arthritis, physical activity’s benefits include reduced pain and improved function, mood, and quality of life.
      • Ambrose K.R.
      • Golightly Y.M.
      Physical exercise as non-pharmacological treatment of chronic pain: why and when.
      Current physical activity levels among U.S. adults with arthritis are unknown. The most recent population-based national estimates were calculated from 2002 National Health Interview Survey (NHIS) data and based on now outdated recommendations (Healthy People 2010, released in 2000

      CDC. Healthy People 2010. www.cdc.gov/nchs/healthy_people/hp2010.htm. Published November 8, 2011. Accessed December 14, 2016.

      and a 2002 U.S. panel comprising physical activity and arthritis experts
      Work Group recommendations: 2002 Exercise and Physical Activity Conference, St. Louis, Missouri
      Session V: evidence of benefit of exercise and physical activity in arthritis.
      ). Healthy People 2010 aerobic activity recommendations for all adults, including those with arthritis, were participation in either moderate-intensity activity ≥30 minutes per day, ≥5 days per week, or vigorous-intensity activity ≥20 minutes per day, ≥3 days per week
      U.S. DHHS
      ; the 2002 panel recommended people with arthritis participate in moderate physical activity ≥30 minutes each day, ≥3 days per week.
      Work Group recommendations: 2002 Exercise and Physical Activity Conference, St. Louis, Missouri
      Session V: evidence of benefit of exercise and physical activity in arthritis.
      The current physical activity guidelines, 2008 Physical Activity Guidelines for Americans (2008 Guidelines), contain recommendations for the general population and for people with specific chronic conditions, including arthritis.
      U.S. DHHS
      2008 Physical Activity Guidelines for Americans.
      They recommend that for substantial health benefits, adults should participate weekly in ≥150 minutes of moderate-intensity aerobic activity, 75 minutes of vigorous-intensity aerobic activity, or an equivalent combination (i.e., equivalent of ≥150 minutes of moderate aerobic physical activity). Furthermore, for more extensive health benefits (e.g., decreased all-cause mortality),
      • Arem H.
      • Moore S.C.
      • Patel A.
      • et al.
      Leisure time physical activity and mortality: a detailed pooled analysis of the dose-response relationship.
      adults should engage in >300 minutes of moderate-intensity equivalent activity each week.
      U.S. DHHS
      2008 Physical Activity Guidelines for Americans.
      The 2008 Guidelines also recommend that adults engage in muscle strengthening activities involving all seven major muscle groups ≥2 days per week to increase bone strength and muscular fitness. Adults meeting both the aerobic and muscle strengthening guidelines fully meet 2008 Guidelines. To the authors’ knowledge, the percentage of U.S. adults with arthritis engaging in muscle strengthening activities and fully meeting the 2008 Guidelines is unknown.
      Contemporary nationally representative population-based physical activity estimates among U.S. adults with arthritis were calculated using NHIS data and the 2008 Guidelines. First, for 2015, the prevalence of each aerobic physical activity level (i.e., active, insufficiently active, inactive) among U.S. adults with arthritis overall and across selected characteristics was estimated. Second, muscle strengthening prevalence overall and across selected characteristics among U.S. adults with arthritis in 2015 was estimated. Third, distribution of physical activity levels (aerobic, muscle strengthening, and both aerobic and muscle strengthening) by arthritis status was examined for 2015. Last, the percentage of adults with and without arthritis meeting each physical activity guideline type (aerobic, muscle strengthening, and both aerobic and muscle strengthening) from 2008 through 2015 was studied.

      Methods

      Data Sample

      In 2016, NHIS data for U.S. adults aged ≥18 years were analyzed. NHIS is an ongoing, in-person, population-based cross-sectional survey that is designed to be representative of the civilian, non-institutionalized population. Final sample adult response rates from 2008 to 2015, accounting for NHIS’ household and family component response rates, ranged from 55.2% in 2015 (lowest) to 66.3% in 2011 (highest).

      CDC. NHIS Survey Description: 2015 National Health Interview Survey (NHIS). ftp://ftp.cdc.gov/pub/Health_Statistics/NCHS/Dataset_Documentation/NHIS/2015/srvydesc.pdf. Published June 2016. Accessed July 1, 2016.

      NHIS is described further at: ftp://ftp.cdc.gov/pub/Health_Statistics/NCHS/Dataset_Documentation/NHIS/2015/srvydesc.pdf.

      CDC. NHIS Survey Description: 2015 National Health Interview Survey (NHIS). ftp://ftp.cdc.gov/pub/Health_Statistics/NCHS/Dataset_Documentation/NHIS/2015/srvydesc.pdf. Published June 2016. Accessed July 1, 2016.

      Measures

      Respondents answering yes to Have you EVER been told by a doctor or other health professional that you have some form of arthritis, rheumatoid arthritis, gout, lupus or fibromyalgia? were classified as having arthritis.
      Three leisure time physical activity measures were examined (leisure time physical activity questions are in Appendix 1, available online):
      • 1.
        Aerobic activity: Respondents reported frequency and duration of leisure time moderate and vigorous aerobic activity during a usual week. Weekly moderate equivalent minutes were calculated by summing moderate- and vigorous-intensity minutes, where 1 minute of vigorous activity equaled 2 minutes of moderate activity. Respondents were classified as active if they engaged in ≥150 minutes of moderate-intensity equivalent activity (i.e., meets aerobic physical activity guideline),
        U.S. DHHS
        Physical Activity Guidelines for Americans.
        insufficiently active if they engaged in some moderate-intensity equivalent activity but did not meet the active definition, and inactive if they reported no moderate-intensity equivalent activity that lasted ≥10 minutes. Those engaging in >300 minutes of moderate-intensity equivalent activity each week were classified as highly active.
      • 2.
        Muscle strengthening: Respondents reporting participation in leisure time physical activities specifically designed to strengthen their muscles (e.g., lifting weights, doing calisthenics) two or more times weekly were classified as meeting the muscle strengthening guideline.
      • 3.
        Fully meeting guidelines was meeting both aerobic activity and muscle strengthening guidelines.

      Statistical Analysis

      Four series of analyses were conducted. First, overall number and percentage (unadjusted and age standardized) of U.S. adults with arthritis in each aerobic activity category (inactive, insufficiently active, and active) were estimated. Then, for each aerobic activity level, age-standardized percentage was calculated across selected sociodemographic characteristics and health status and behaviors (Appendix 2, available online). Second, this analysis was repeated for muscle strengthening. Third, age-standardized prevalence of meeting aerobic activity, muscle strengthening, and both guidelines from 2008 to 2015, by arthritis status, was examined. Last, age-standardized distribution of physical activity levels, by arthritis status, was examined for 2015.
      Analyses, conducted using SAS, version 9.3 and SUDAAN, version 11, accounted for NHIS’ complex design. Estimates were standardized to the 2000 projected U.S. population (age groups were 18–44, 45–64, and ≥65 years).
      • Klein R.J.
      • Schoenborn C.A.
      Age adjustment using the 2000 projected U.S. population.
      Differences in estimates were interpreted as statistically significant when 95% CIs did not overlap. Differences were formally tested with t-tests, by arthritis status, in age-standardized prevalence of physical activity levels. Time trends in age-standardized prevalence were tested using orthogonal linear polynomial contrasts at α=0.05.
      Research Triangle Institute
      Respondents with missing arthritis status were excluded from all analyses; in 2015, this represented 0.2% (weighted percentage) of adults in the U.S. civilian non-institutionalized population. For each physical activity measure, analyses were limited to those providing complete information for this measure; in 2015, missing responses (weighted percentage) across measures ranged from 0.8% (muscle strengthening) to 1.9% (meeting both guidelines).

      Results

      All estimates are based on self-reported information. In 2015, approximately one in five U.S. adults had arthritis (prevalence, 22.9%; age-standardized prevalence, 21.0%).
      In 2015, 36.2% (19.8 million) of all U.S. adults with arthritis were active (i.e., met aerobic physical activity guideline), 22.6% (12.3 million) were insufficiently active, and 41.2% (22.5 million) were inactive (Table 1). Twenty-three percent (12.5 million) of all U.S. adults with arthritis were highly active (data not shown).
      Table 1Prevalence (Weighted) of Aerobic Activity Levels
      Based on the 2008 Physical Activity Guidelines for Americans. Active was ≥150 minutes of moderate-intensity aerobic activity, 75 minutes of vigorous-intensity aerobic activity, or an equivalent combination per week (i.e., met aerobic physical activity guideline). Insufficiently active was some aerobic activity but not enough to meet the active definition. Inactive was no moderate or vigorous-intensity aerobic activity for at least 10 minutes.
      Among U.S. Adults With Arthritis Aged ≥18 Years, 2015
      Derived from 2015 National Health Interview Survey data. There were 8,562 respondents with arthritis who provided complete information on aerobic activity. Participants with unknown values for the characteristics of interest were excluded; across characteristics examined, the percentage (weighted) of missing information ranged from 0.02% for arthritis-attributable activity limitations to 4.6% for psychological distress.
      CharacteristicsAerobic activity levels
      InactiveInsufficiently activeActive
      All estimates ≥50.0% are boldface.
      n
      Number of respondents with arthritis at this aerobic activity level.
      % (95% CI)n
      Number of respondents with arthritis at this aerobic activity level.
      % (95% CI)n
      Number of respondents with arthritis at this aerobic activity level.
      % (95% CI)
      Overall
       Unadjusted3,71441.2 (39.7, 42.7)1,87822.6 (21.3, 23.9)2,97036.2 (34.8, 37.7)
       Age standardized
      Standardized to 2000 U.S. projected population (age groups were 18–44, 45–64, and ≥65 years).
      3,71435.8 (33.4, 38.3)1,87822.3 (20.4, 24.4)2,97041.9 (39.5, 44.3)
      Sociodemographic characteristics
       Age groups
        18−44 years32130.2 (26.1, 34.7)23021.7 (18.3, 25.5)50348.1 (43.9, 52.3)
        45−64 years36839.7 (37.5, 42.0)79623.8 (21.8, 25.9)1,19936.5 (34.4, 38.8)
        ≥65 years2,02546.4 (44.3, 48.6)85221.7 (19.9, 23.5)1,26831.9 (29.9, 34.0)
       Sex
      Standardized to 2000 U.S. projected population (age groups were 18–44, 45–64, and ≥65 years).
        Men1,29334.4 (30.9, 38.0)64720.6 (17.8, 23.7)1,26245.0 (41.4, 48.7)
        Women2,42136.9 (34.0, 39.8)1,23123.6 (21.1, 26.4)1,70839.5 (36.6, 42.5)
       Race/ethnicity
      Standardized to 2000 U.S. projected population (age groups were 18–44, 45–64, and ≥65 years).
        Hispanic40743.8 (37.9, 49.9)16818.6 (15.0, 22.8)24137.6 (32.4, 43.1)
        Non-Hispanic Asian7732.0 (24.8, 40.1)
      Estimate not reported because relative SE ≥30 and/or denominator contained less than 50 respondents.
      10047.7 (39.7, 55.8)
        Non-Hispanic black62639.3 (33.9, 45.0)28926.8 (21.8, 32.5)33933.8 (28.3, 39.8)
        Non-Hispanic other
      Includes non-Hispanic American Indians and Alaska Natives. There was insufficient sample size to report estimate for this race/ethnicity group separately.
      12329.7 (19.9, 41.8)7521.7 (14.3, 31.5)14548.6 (36.8, 60.5)
        Non-Hispanic white2,55834.5 (31.6, 37.4)1,34622.1 (19.9, 24.5)2,24543.4 (40.5, 46.4)
       Highest educational attainment
      Standardized to 2000 U.S. projected population (age groups were 18–44, 45–64, and ≥65 years).
        Less than high school85856.1 (48.8, 63.2)24518.5 (13.9, 24.2)26725.4 (19.6, 32.2)
        High school graduate1,18141.5 (36.8, 46.3)56124.6 (20.4, 29.4)64133.9 (29.6, 38.6)
        Technical college/some university1,10635.0 (31.3, 38.9)61523.7 (20.4, 27.3)97041.4 (37.3, 45.5)
        At least university degree54121.5 (18.5, 24.8)45020.2 (17.2, 23.7)1,08558.3 (54.5, 62.0)
       Current employment status
      Standardized to 2000 U.S. projected population (age groups were 18–44, 45–64, and ≥65 years).
        Working88927.2 (24.5, 30.1)75422.2 (20.0, 24.5)1,40650.6 (47.7, 53.5)
        Unable to work93259.9 (53.9, 65.7)27621.2 (16.8, 26.5)22918.8 (14.5, 24.0)
        Other
      Comprises unemployed, retired, students, and homemakers.
      1,89235.6 (30.4, 41.1)84824.3 (19.4, 30.0)1,33340.1 (35.0, 45.5)
      Health status and behaviors
       Arthritis-attributable activity limitations
      Standardized to 2000 U.S. projected population (age groups were 18–44, 45–64, and ≥65 years).
        No1,52927.1 (24.6, 29.7)1,05722.4 (20.0, 25.1)2,02250.5 (47.4, 53.5)
        Yes2,18447.7 (43.9, 51.5)82122.1 (19.4, 25.1)94730.2 (27.0, 33.6)
       Self-rated health
      Standardized to 2000 U.S. projected population (age groups were 18–44, 45–64, and ≥65 years).
        Excellent/very good80623.4 (20.5, 26.5)68121.5 (18.7, 24.6)1,59355.1 (51.6, 58.6)
        Good1,21333.7 (29.6, 38.0)69624.3 (21.0, 27.9)96542.1 (38.0, 46.3)
        Fair/poor1,69556.5 (51.7, 61.3)50021.4 (17.8, 25.5)41022.1 (18.3, 26.3)
       Comorbidities
      Standardized to 2000 U.S. projected population (age groups were 18–44, 45–64, and ≥65 years).
        060828.8 (25.9, 32.0)40921.2 (18.3, 24.5)90249.9 (46.4, 53.4)
        1−21,87235.5 (32.1, 39.0)1,01722.4 (19.6, 25.6)1,64742.1 (38.6, 45.7)
        3−101,23453.5 (46.5, 60.3)45227.0 (20.5, 34.6)42119.5 (14.6, 25.5)
       Psychological distress
      Standardized to 2000 U.S. projected population (age groups were 18–44, 45–64, and ≥65 years).
        None to mild2,26531.7 (28.9, 34.6)1,28422.1 (19.5, 25.0)2,21046.2 (43.1, 49.2)
        Moderate88036.8 (33.2, 40.7)43424.9 (21.3, 29.0)55038.2 (34.3, 42.3)
        Serious37361.3 (53.1, 68.9)10820.3 (14.4, 27.7)10418.4 (12.9, 25.6)
       Functional limitations
      Standardized to 2000 U.S. projected population (age groups were 18–44, 45–64, and ≥65 years).
      ,
      Functional limitations in this measure are: walk a quarter mile, walk up 10 steps, stand for 2 hours, sit for 2 hours, stoop/bend/kneel, reach overhead, grasp small objects, lift/carry up to 10 pounds, and push/pull large objects.
        01,26824.9 (22.7, 27.3)1,04622.5 (20.3, 24.8)2,22952.6 (50.0, 55.3)
        1−31,11643.5 (38.1, 49.1)57226.9 (22.0, 32.5)57929.6 (25.2, 34.3)
        4−91,33076.9 (70.9, 81.9)26013.2 (9.7, 17.9)1629.9 (6.7, 14.3)
       Social participation restrictions
      Standardized to 2000 U.S. projected population (age groups were 18–44, 45–64, and ≥65 years).
        No2,87132.6 (30.3, 35.1)1,70122.6 (20.5, 24.7)2,86544.8 (42.4, 47.2)
        Yes84365.3 (56.6, 73.0)17721.1 (14.8, 29.0)10513.6 (8.9, 20.4)
       Need special equipment
      Standardized to 2000 U.S. projected population (age groups were 18–44, 45–64, and ≥65 years).
        No2,37731.9 (29.5, 34.5)1,51222.5 (20.5, 24.6)2,66045.6 (43.1, 48.0)
        Yes1,33754.5 (47.2, 61.7)36622.4 (16.6, 29.5)31023.1 (17.3, 30.2)
       Current smoking status
      Standardized to 2000 U.S. projected population (age groups were 18–44, 45–64, and ≥65 years).
        Never1,78331.7 (28.6, 34.9)93322.0 (19.4, 24.9)1,54846.3 (43.1, 49.6)
        Former1,16134.0 (29.3, 39.1)65324.2 (19.8, 29.2)1,04241.8 (36.8, 47.0)
        Current76649.1 (44.4, 53.8)28720.9 (17.4, 24.9)37630.0 (25.8, 34.5)
       BMI
      Standardized to 2000 U.S. projected population (age groups were 18–44, 45–64, and ≥65 years).
        Underweight/normal weight (<25.0)92533.1 (28.9, 37.5)42520.2 (16.4, 24.6)85646.8 (42.3, 51.2)
        Overweight (25.0 to <30.0)1,04235.8 (31.7, 40.1)60319.5 (16.5, 22.8)1,04244.7 (40.7, 48.9)
        Obese (≥30.0)1,59637.1 (33.8, 40.5)78825.8 (22.7, 29.1)99337.1 (33.7, 40.7)
      a Based on the 2008 Physical Activity Guidelines for Americans. Active was ≥150 minutes of moderate-intensity aerobic activity, 75 minutes of vigorous-intensity aerobic activity, or an equivalent combination per week (i.e., met aerobic physical activity guideline). Insufficiently active was some aerobic activity but not enough to meet the active definition. Inactive was no moderate or vigorous-intensity aerobic activity for at least 10 minutes.
      b Derived from 2015 National Health Interview Survey data. There were 8,562 respondents with arthritis who provided complete information on aerobic activity. Participants with unknown values for the characteristics of interest were excluded; across characteristics examined, the percentage (weighted) of missing information ranged from 0.02% for arthritis-attributable activity limitations to 4.6% for psychological distress.
      c Number of respondents with arthritis at this aerobic activity level.
      d All estimates ≥50.0% are boldface.
      e Standardized to 2000 U.S. projected population (age groups were 18–44, 45–64, and ≥65 years).
      f Estimate not reported because relative SE ≥30 and/or denominator contained less than 50 respondents.
      g Includes non-Hispanic American Indians and Alaska Natives. There was insufficient sample size to report estimate for this race/ethnicity group separately.
      h Comprises unemployed, retired, students, and homemakers.
      i Functional limitations in this measure are: walk a quarter mile, walk up 10 steps, stand for 2 hours, sit for 2 hours, stoop/bend/kneel, reach overhead, grasp small objects, lift/carry up to 10 pounds, and push/pull large objects.
      The age-specific percentage of adults with arthritis who were active was highest among younger adults (aged 18–44 years) and declined with increasing age. The age-standardized percentage of adults with arthritis who were active rose with increasing levels of education and self-rated health and declined with increasing number of comorbidities, severity of psychological distress, number of functional limitations, and BMI (Table 1). At least half (age-standardized percentage, 50.0%) of adults with arthritis in the following five groups were active: had at least a university degree (58.3%), excellent or very good general self-rated health (55.1%), no functional limitations (52.6%), were currently working (50.6%), and had no arthritis-attributable activity limitations (50.5%).
      Across studied characteristics, the age-standardized percentage who were insufficiently active ranged from 13.2% to 27.0%. Finally, patterns across characteristics of those who were inactive were generally the reverse of patterns for being active (e.g., percentage who were inactive was lowest and highest among younger and older adults, respectively).
      An estimated 17.9% (9.9 million) of U.S. adults with arthritis engaged in muscle strengthening at least twice a week (age-standardized prevalence, 19.5%) (Table 2). The percentage meeting muscle strengthening guideline was ≥25.0% for only two groups: those with at least a university degree (31.3%) and those with excellent or very good self-rated health (26.6%) (Table 2).
      Table 2Prevalence (Weighted) of Muscle Strengthening Activities
      Based on the 2008 Physical Activity Guidelines for Americans. Muscle strengthening guideline was defined as performing muscle strengthening activities two or more times per week.
      Among U.S. Adults With Arthritis Aged ≥18 Years, 2015
      Derived from 2015 National Health Interview Survey data. There were 8,630 respondents with arthritis who provided complete information on muscle strengthening activity; across characteristics examined. Participants with unknown values for the characteristics of interest were excluded; across characteristics, the percentage (weighted) of missing information ranged from 0.02% for arthritis-attributable activity limitations to 4.6% for psychological distress.
      CharacteristicsMuscle strengthening activities
      <2 times/week≥2 times/week
      All estimates ≥25.0% are boldface.
      n
      Number of respondents with arthritis at this muscle strengthening activity level.
      % (95% CI)n
      Number of respondents with arthritis at this muscle strengthening activity level.
      % (95% CI)
      Overall
       Unadjusted7,13082.1 (80.9, 83.1)1,50017.9 (16.9, 19.1)
       Age standardized
      Standardized to 2000 U.S. projected population (age groups were 18 to 44, 45 to 64, and ≥65 years).
      7,13080.5 (78.7, 82.2)1,50019.5 (17.8, 21.3)
      Sociodemographic characteristics
       Age groups
        18−44 years81579.0 (75.8, 81.9)24121.0 (18.1, 24.2)
        45−64 years2,79881.3 (79.5, 83.1)58718.7 (16.9, 20.5)
        ≥65 years3,51783.8 (82.2, 85.3)67216.2 (14.7, 17.8)
       Sex
      Standardized to 2000 U.S. projected population (age groups were 18 to 44, 45 to 64, and ≥65 years).
        Men2,60679.3 (76.5, 81.9)62720.7 (18.1, 23.5)
        Women4,52481.5 (79.2, 83.6)87318.5 (16.4, 20.8)
       Race/ethnicity
      Standardized to 2000 U.S. projected population (age groups were 18 to 44, 45 to 64, and ≥65 years).
        Hispanic71083.3 (78.2, 87.5)10916.7 (12.5, 21.8)
        Non-Hispanic American Indians and Alaska Natives7484.6 (72.3, 92.0)
      Estimate not reported because relative SE ≥30 and/or denominator contained less than 50 respondents.
        Non-Hispanic Asian18580.1 (71.8, 86.5)
      Estimate not reported because relative SE ≥30 and/or denominator contained less than 50 respondents.
        Non-Hispanic black1,07979.8 (74.7, 84.1)19020.2 (15.9, 25.3)
        Non-Hispanic other28178.8 (68.2, 86.6)6521.2 (13.4, 31.8)
        Non-Hispanic white5,06080.4 (78.2, 82.5)1,13619.6 (17.5, 21.8)
       Highest educational attainment
      Standardized to 2000 U.S. projected population (age groups were 18 to 44, 45 to 64, and ≥65 years).
        Less than high school1,27891.3 (86.3, 94.6)1068.7 (5.4, 13.7)
        High school graduate2,13086.2 (82.4, 89.3)27913.8 (10.7, 17.6)
        Technical college/some university2,21981.3 (78.2, 84.0)49018.7 (16.0, 21.8)
        At least university degree1,46468.7 (65.2, 72.0)62231.3 (28.0, 34.8)
       Current employment status
      Standardized to 2000 U.S. projected population (age groups were 18 to 44, 45 to 64, and ≥65 years).
        Working2,38276.6 (73.9, 79.0)67923.4 (21.0, 26.1)
        Unable to work1,33092.4 (89.6, 94.5)1217.6 (5.5, 10.4)
        Other
      Comprises unemployed, retired, students, and homemakers.
      3,41579.0 (74.2, 83.1)70021.0 (16.9, 25.8)
      Health status and behaviors
       Arthritis attributable activity limitations
      Standardized to 2000 U.S. projected population (age groups were 18 to 44, 45 to 64, and ≥65 years).
        No3,63976.0 (73.6, 78.3)1,00124.0 (21.7, 26.4)
        Yes3,48986.6 (83.8, 88.9)49913.4 (11.1, 16.2)
       Self-rated health
      Standardized to 2000 U.S. projected population (age groups were 18 to 44, 45 to 64, and ≥65 years).
        Excellent/very good2,27473.4 (70.3, 76.3)82226.6 (23.7, 29.7)
        Good2,45581.7 (78.1, 84.9)45918.3 (15.1, 21.9)
        Fair/poor2,39889.7 (86.9, 92.0)21810.3 (8.0, 13.1)
       Comorbidities
      Standardized to 2000 U.S. projected population (age groups were 18 to 44, 45 to 64, and ≥65 years).
        01,45775.5 (72.5, 78.2)47424.5 (21.8, 27.5)
        1−23,77681.0 (78.2, 83.6)80019.0 (16.4, 21.8)
        3−101,89791.5 (87.8, 94.2)2268.5 (5.8, 12.2)
       Psychological distress
      Standardized to 2000 U.S. projected population (age groups were 18 to 44, 45 to 64, and ≥65 years).
        None to mild4,67976.6 (73.9, 79.1)1,12523.4 (20.9, 26.1)
        Moderate1,59985.6 (83.1, 87.8)27914.4 (12.2, 16.9)
        Serious54193.1 (88.5, 95.9)506.9 (4.1, 11.5)
       Functional limitations
      Standardized to 2000 U.S. projected population (age groups were 18 to 44, 45 to 64, and ≥65 years).
      ,
      Functional limitations in this measure are: walk a quarter mile, walk up 10 steps, stand for 2 hours, sit for 2 hours, stoop/bend/kneel, reach overhead, grasp small objects, lift/carry up to 10 pounds, and push/pull large objects.
        03,50975.8 (73.5, 77.9)1,06024.2 (22.1, 26.5)
        1−31,98486.6 (83.3, 89.4)31513.4 (10.6, 16.7)
        4−91,63793.8 (90.9, 95.8)1256.2 (4.2, 9.1)
       Social participation restrictions
      Standardized to 2000 U.S. projected population (age groups were 18 to 44, 45 to 64, and ≥65 years).
        No6,10279.6 (77.6, 81.4)1,40020.4 (18.6, 22.4)
        Yes1,02889.9 (83.7, 93.9)10010.1 (6.1, 16.3)
       Need special equipment
      Standardized to 2000 U.S. projected population (age groups were 18 to 44, 45 to 64, and ≥65 years).
        No5,32379.0 (77.1, 80.9)1,27921.0 (19.1, 22.9)
        Yes1,80788.5 (82.8, 92.4)22111.5 (7.6, 17.2)
       Current smoking status
      Standardized to 2000 U.S. projected population (age groups were 18 to 44, 45 to 64, and ≥65 years).
        Never3,48576.3 (73.6, 78.7)81723.7 (21.3, 26.4)
        Former2,32880.2 (75.4, 84.2)54519.8 (15.8, 24.6)
        Current1,30791.0 (88.1, 93.2)1349.0 (6.8, 11.9)
       BMI
      Standardized to 2000 U.S. projected population (age groups were 18 to 44, 45 to 64, and ≥65 years).
        Underweight /normal weight (<25.0)1,72876.2 (72.2, 79.8)49523.8 (20.2, 27.8)
        Overweight (25.0−<30.0)2,20180.9 (77.8, 83.7)51519.1 (16.3, 22.2)
        Obese (≥30.0)2,94082.9 (80.3, 85.2)46017.1 (14.8, 19.7)
      a Based on the 2008 Physical Activity Guidelines for Americans. Muscle strengthening guideline was defined as performing muscle strengthening activities two or more times per week.
      b Derived from 2015 National Health Interview Survey data. There were 8,630 respondents with arthritis who provided complete information on muscle strengthening activity; across characteristics examined. Participants with unknown values for the characteristics of interest were excluded; across characteristics, the percentage (weighted) of missing information ranged from 0.02% for arthritis-attributable activity limitations to 4.6% for psychological distress.
      c Number of respondents with arthritis at this muscle strengthening activity level.
      d All estimates ≥25.0% are boldface.
      e Standardized to 2000 U.S. projected population (age groups were 18 to 44, 45 to 64, and ≥65 years).
      f Estimate not reported because relative SE ≥30 and/or denominator contained less than 50 respondents.
      g Comprises unemployed, retired, students, and homemakers.
      h Functional limitations in this measure are: walk a quarter mile, walk up 10 steps, stand for 2 hours, sit for 2 hours, stoop/bend/kneel, reach overhead, grasp small objects, lift/carry up to 10 pounds, and push/pull large objects.
      An estimated 13.7% (7.5 million) of U.S. adults with arthritis (age-standardized percentage, 15.8%) met both aerobic and muscle strengthening guidelines (Appendix 3, available online). Across characteristics, the prevalence of meeting both guidelines was ≥25.0% in only one group: those with at least a university degree (26.6%).
      From 2008 through 2015, the age-standardized percentage of U.S. adults with arthritis who were active (i.e., met aerobic physical activity guideline) increased by almost 3 percentage points (39.2% [95% CI=36.4%, 42.1%] in 2008 and 41.9% [95% CI=39.5%, 44.3%] in 2015; test for trend, p=0.02). The increase was larger (7 percentage points) among those without arthritis (45.0% [95% CI=43.9%, 46.2%] in 2008 and 52.2% [95% CI=51.2%, 53.2%] in 2015; test for trend, p<0.001) (Figure 1).
      Figure 1.
      Figure 1Age-standardizeda percentage who met each type of guideline, by arthritis status, 2008–2015 National Health Interview Survey.
      Note: Black bar represents those with arthritis. Gray bar represents those without arthritis. Line is 95% CI.
      aStandardized to 2000 U.S. projected population.
      Test for trend, p<0.05.
      From 2008 through 2015, the prevalence of meeting muscle strengthening guideline among adults with arthritis remained statistically identical (test for trend, p=0.69). Although the prevalence for those with and without arthritis in 2008 was statistically the same, there was a modest (3 percentage point) and statistically significant increase in the percentage of adults without arthritis meeting the muscle strengthening guideline in subsequent years (test for trend, p<0.001). For those with and without arthritis, the pattern of fully meeting guidelines over time was largely similar to the patterns in muscle strengthening prevalence (test for trend among those with and without arthritis was p=0.63 and p<0.001, respectively).
      In 2015, the age-standardized percentage of adults with arthritis who were aerobically active was 10 percentage points lower than those without arthritis (p<0.001) (Figure 1, Figure 2). Likewise, the percentage of adults without arthritis who were highly active was also higher than those with arthritis (35.6% [95% CI=34.6%, 36.6%] and 27.7% [95% CI=25.6%, 29.9%], respectively; p<0.001). Correspondingly, relative to those without arthritis, a higher percentage of adults with arthritis was inactive (35.8% [95% CI=33.4%, 38.3%] and 28.5% [95% CI=27.6%, 29.5%]; p<0.001) and insufficiently active (22.3% [95% CI=20.4%, 24.4%] and 19.2% [95% CI=18.5%, 20.0%]; p<0.01).
      Figure 2.
      Figure 2Age-standardizeda prevalence of physical activity levels, by arthritis status, 2015 National Health Interview Survey.
      Note: White bar represents those with arthritis. Gray bar represents those without arthritis. Line is 95% CI.
      aStandardized to 2000 U.S. projected population.
      The age-standardized percentage of adults meeting muscle strengthening guideline was 6 percentage points lower among those with arthritis compared with those without (19.5% [95% CI=17.8%, 21.3%] and 25.9% [95% CI=25.1%, 26.7%]; p<0.001) (Figure 1, Figure 2). Similarly, the percentage of adults with arthritis who fully met guidelines (both aerobic and muscle strengthening) was almost 7 percentage points lower among those with arthritis (15.8%, 95% CI=14.2%, 17.6%) than those without (22.6%, 95% CI=21.9%, 23.4%) (p<0.001) (Figure 1, Figure 2).

      Discussion

      In 2015, 36.2% (19.8 million) of U.S. adults with arthritis met the aerobic physical activity guideline, 17.9% (9.9 million) met the muscle strengthening guideline, and 13.7% (7.5 million) met both guidelines. Although based on different guidelines, the characteristics of adults with arthritis with the highest prevalence of aerobic inactivity in this study were generally similar to those with arthritis in the 2002 NHIS: being older, less educated, and having poorer physical and psychosocial health (e.g., functional limitations, comorbidities, serious psychological distress, social participation restrictions).
      • Shih M.
      • Hootman J.M.
      • Kruger J.
      • Helmick C.G.
      Physical activity in men and women with arthritis National Health Interview Survey, 2002.
      Patterns in meeting aerobic activity guideline across age, sex, highest educational attainment, and BMI in this study were similar to those for U.S. adults overall in the 2008 NHIS.
      • Carlson S.A.
      • Fulton J.E.
      • Schoenborn C.A.
      • Loustalot F.
      Trend and prevalence estimates based on the 2008 Physical Activity Guidelines for Americans.
      Across all years, only one in five adults with arthritis met the muscle strengthening guideline. Muscle strengthening has many overall (e.g., decreased all-cause mortality and bone mineral density loss)
      • Kraschnewski J.L.
      • Sciamanna C.N.
      • Poger J.M.
      • et al.
      Is strength training associated with mortality benefits? A 15 year cohort study of U.S. older adults.
      • Seguin R.
      • Nelson M.E.
      The benefits of strength training for older adults.
      and arthritis-specific (e.g., reduced disability and pain) benefits.
      • Roddy E.
      • Zhang W.
      • Doherty M.
      Aerobic walking or strengthening exercise for osteoarthritis of the knee? A systematic review.
      One can participate in muscle strengthening with limited space and equipment (dumbbells, stretch bands, using own weight) and therefore it may be more accessible for those who cannot leave their home because of limited mobility or problematic weather. Although engaging in both aerobic and strengthening activities is optimal for maximizing physical activity’s benefits, having a choice between aerobic and muscle strengthening exercises may increase adherence to physical activity.
      • Roddy E.
      • Zhang W.
      • Doherty M.
      Aerobic walking or strengthening exercise for osteoarthritis of the knee? A systematic review.
      Thus, increasing awareness about muscle strengthening’s benefits, convenience, and safety may be an important strategy for increasing physical activity.
      In 2015, the percentage meeting each guideline was considerably lower among adults with arthritis compared with those without; this difference has been reported previously.
      • Shih M.
      • Hootman J.M.
      • Kruger J.
      • Helmick C.G.
      Physical activity in men and women with arthritis National Health Interview Survey, 2002.
      • Fontaine K.R.
      • Haaz S.
      Risk factors for lack of recent exercise in adults with self-reported, professionally diagnosed arthritis.
      • Hootman J.M.
      • Macera C.A.
      • Ham S.A.
      • Helmick C.G.
      • Sniezek J.E.
      Physical activity levels among the general U.S. adult population and in adults with and without arthritis.
      Across the 8 years studied here, the percentage of adults with arthritis meeting aerobic guideline increased slightly (3 percentage points and statistically significant test for trend), whereas the percentage meeting muscle strengthening and full guidelines remained the same. By contrast, adults without arthritis experienced larger and statistically significant increases for each guideline. Adults with arthritis report both generic and arthritis-specific barriers to physical activity (e.g., functional limitations, fear that physical activity will worsen pain).
      • Stone R.C.
      • Baker J.
      Painful choices: a qualitative exploration of facilitators and barriers to active lifestyles among adults with osteoarthritis.
      • Wilcox S.
      • Der Ananian C.
      • Abbott J.
      • et al.
      Perceived exercise barriers, enablers, and benefits among exercising and nonexercising adults with arthritis: results from a qualitative study.
      • Iversen M.D.
      • Scanlon L.
      • Frits M.
      • Shadick N.A.
      • Sharby N.
      Perceptions of physical activity engagement among adults with rheumatoid arthritis and rheumatologists.
      Multiple evidence-based strategies for promoting and supporting physical activity among adults with arthritis exist, but the minimal increase in this study suggests that these approaches are underused. Although there is currently no evidence that specific medical interventions increase physical activity (e.g., a recent meta-analysis of people with osteoarthritis found no increase in physical activity after total knee or hip arthroplasty
      • Arnold J.B.
      • Walters J.L.
      • Ferrar K.E.
      Does physical activity increase after total hip or knee arthroplasty for osteoarthritis? A systematic review.
      ), healthcare providers may increase physical activity among adults with arthritis through medical management of physical activity barriers (e.g., pain), counseling all patients with arthritis to engage in physical activity to manage their arthritis symptoms,

      Bartlett S. Role of Exercise in Arthritis Management. Managing Your Arthritis. www.hopkinsarthritis.org/patient-corner/disease-management/role-of-exercise-in-arthritis-management/. Published 2011. Accessed January 19, 2017.

      and referring patients to community, evidence-based physical activity programs. Though the percentage of healthcare providers who recommend physical activity to their patients with arthritis is rising, currently two in five do not receive this recommendation.
      National Center for Health Statistics
      Arthritis, osteoporosis, and chronic back conditions. Healthy People 2020 Midcourse Review.
      Patients report that insufficient support from healthcare providers is a barrier to physical activity,
      • Wilcox S.
      • Der Ananian C.
      • Abbott J.
      • et al.
      Perceived exercise barriers, enablers, and benefits among exercising and nonexercising adults with arthritis: results from a qualitative study.
      • Iversen M.D.
      • Fossel A.H.
      • Daltroy L.H.
      Rheumatologist-patient communication about exercise and physical therapy in the management of rheumatoid arthritis.
      which is consistent with primary care providers’ and rheumatologists’ reports that they do not discuss physical activity with their patients for multiple reasons, including limited appointment time.
      • Iversen M.D.
      • Scanlon L.
      • Frits M.
      • Shadick N.A.
      • Sharby N.
      Perceptions of physical activity engagement among adults with rheumatoid arthritis and rheumatologists.
      • AuYoung M.
      • Linke S.E.
      • Pagoto S.
      • et al.
      integrating physical activity in primary care practice.
      Exercise Is Medicine® guidelines, developed to help healthcare providers address barriers and increase physical activity among their patients, include the recommendation that healthcare providers refer their patients to exercise professionals or local community programs.

      American College of Sports Medicine (ACSM). Exercise is Medicine. Healthcare Providers׳ Action Guide. http://exerciseismedicine.org/assets/page_documents/Complete%20HCP%20Action%20Guide_2016_01_01.pdf. Accessed May 26, 2016.

      Evidence-based physical activity programs (e.g., Walk with Ease, EnhanceFitness),

      CDC. Intervention Programs. Physical Activity Programs. www.cdc.gov/arthritis/interventions/physical-activity.html. Published 2016. Accessed July 25, 2016.

      designed to address arthritis-specific barriers, are available in many communities throughout the U.S. Public health professionals can support healthcare providers by ensuring that people with arthritis and healthcare providers are aware of these programs and striving to ensure complete geographic coverage of these programs in the U.S.
      In 2015, one in four U.S. adults with arthritis were highly aerobically active compared with approximately one in three without arthritis. Currently, there is no evidence that adults with arthritis who are highly active (i.e., >300 moderate equivalent minutes) experience greater arthritis-specific benefits than those who are sufficiently active. However, being highly active confers other benefits, including reduced condition-specific mortality (e.g., cardiovascular disease, specific types of cancer [e.g., breast]
      • Li T.
      • Wei S.
      • Shi Y.
      • et al.
      The dose-response effect of physical activity on cancer mortality: findings from 71 prospective cohort studies.
      ) and all-cause mortality.
      • Arem H.
      • Moore S.C.
      • Patel A.
      • et al.
      Leisure time physical activity and mortality: a detailed pooled analysis of the dose-response relationship.
      In this study, approximately three quarters of those with arthritis had at least one comorbidity and the prevalence of meeting aerobic and muscle strengthening guidelines decreased with increasing number of comorbidities. Thus, although many adults with arthritis may have a higher need for the benefits of being highly active, they are less likely to experience these effects than those without arthritis.

      Limitations

      This study’s limitations include the following. First, NHIS data are cross-sectional and therefore causal relationships cannot be inferred. Second, physical activity was self-reported and may be overestimated.
      • Sallis J.F.
      • Saelens B.E.
      Assessment of physical activity by self-report: status, limitations, and future directions.
      In two studies comprising middle-aged and older adults with osteoarthritis, the percentage meeting aerobic physical activity guideline, when human movement was measured with an accelerometer, was 7.3%−12.9% and 6.3%−7.7% among men and women, respectively.
      • Dunlop D.D.
      • Song J.
      • Semanik P.A.
      • et al.
      Objective physical activity measurement in the osteoarthritis initiative: are guidelines being met?.
      • White D.K.
      • Tudor-Locke C.
      • Felson D.T.
      • et al.
      Do radiographic disease and pain account for why people with or at high risk of knee osteoarthritis do not meet physical activity guidelines?.
      These percentages are considerably smaller than the 41.9% meeting aerobic guideline in this study. Another possible source of overestimation: Whereas 2008 Guidelines do not include “light-intensity” activities, moderate activity in the NHIS uses a single question to measure both “light-intensity” and “moderate-intensity” activity. Third, NHIS data do not reflect whether reported muscle strengthening activities involved the seven major muscle groups specified in the 2008 Guidelines and may overestimate the prevalence of meeting muscle strengthening guideline.
      • Loustalot F.
      • Carlson S.A.
      • Kruger J.
      • Buchner D.M.
      • Fulton J.E.
      Muscle-strengthening activities and participation among adults in the United States.
      Fourth, the physical activity measure captures leisure time activity only, which does not account for physical activity during work or transportation. Last, arthritis was self-reported. A clinic-based validation study of this question reported 77%−84% sensitivity and 59%−71% specificity, indicating likely misclassification of arthritis. Although the effect of this misclassification on this study’s estimates is unclear, the study conclusion would likely be similar in the absence of misclassification: A high percentage of adults with arthritis do not meet current aerobic or muscle strengthening guidelines.
      A strength of this study was the data source, a population-based survey that measures numerous health status and behavior characteristics, including physical activity. The large sample size generated statistically precise estimates. The NHIS’ ongoing nature allowed study of 8 consecutive years. These are presumptively the first population physical activity estimates among U.S. adults with arthritis based on the 2008 Guidelines.

      Conclusions

      Overall, the results indicate that although approximately one in three and one in five U.S. adults with arthritis are meeting aerobic and muscle strengthening guidelines, respectively, a substantial percentage of U.S. adults with arthritis engage in no leisure time physical activity each week. Public health professionals and healthcare providers have an important role in helping people with arthritis increase physical activity levels, thus ensuring that they experience physical activity’s numerous generic and arthritis-specific benefits.

      Acknowledgments

      The authors thank Jeffrey Sacks, MD, MPH for his thoughtful review of the manuscript.
      The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.
      No financial disclosures were reported by the authors of this paper.

      Supplementary material

      References

        • U.S. DHHS
        2008 Physical Activity Guidelines for Americans.
        U.S. DHHS, Washington, DC2008
      1. Physical Activity Guidelines Advisory Committee. Physical Activity Guidelines Advisory Committee Report, 2008. http://health.gov/paguidelines/report/. Accessed May 26, 2016.

        • Ambrose K.R.
        • Golightly Y.M.
        Physical exercise as non-pharmacological treatment of chronic pain: why and when.
        Best Pract Res Clin Rheumatol. 2015; 29: 120-130https://doi.org/10.1016/j.berh.2015.04.022
      2. CDC. Healthy People 2010. www.cdc.gov/nchs/healthy_people/hp2010.htm. Published November 8, 2011. Accessed December 14, 2016.

        • Work Group recommendations: 2002 Exercise and Physical Activity Conference, St. Louis, Missouri
        Session V: evidence of benefit of exercise and physical activity in arthritis.
        Arthritis Rheum. 2003; 49: 453-454https://doi.org/10.1002/art.11125
        • U.S. DHHS
        Healthy People 2010: Understanding and Improving Health. 2nd edition. U.S. Government Printing Office, Washington DC2000
        • Shih M.
        • Hootman J.M.
        • Kruger J.
        • Helmick C.G.
        Physical activity in men and women with arthritis National Health Interview Survey, 2002.
        Am J Prev Med. 2006; 30: 385-393https://doi.org/10.1016/j.amepre.2005.12.005
        • Arem H.
        • Moore S.C.
        • Patel A.
        • et al.
        Leisure time physical activity and mortality: a detailed pooled analysis of the dose-response relationship.
        JAMA Intern Med. 2015; 175: 959-967https://doi.org/10.1001/jamainternmed.2015.0533
      3. CDC. NHIS Survey Description: 2015 National Health Interview Survey (NHIS). ftp://ftp.cdc.gov/pub/Health_Statistics/NCHS/Dataset_Documentation/NHIS/2015/srvydesc.pdf. Published June 2016. Accessed July 1, 2016.

        • U.S. DHHS
        Physical Activity Guidelines for Americans.
        (October) U.S. DHHS, Washington, DC2008
        • Klein R.J.
        • Schoenborn C.A.
        Age adjustment using the 2000 projected U.S. population.
        Healthy People 2010 Stat Notes. 2001; : 1-10
        • Research Triangle Institute
        SUDAAN Language Manual. 11 ed. Research Triangle Institute, Research Triangle Park, NC2012
        • Carlson S.A.
        • Fulton J.E.
        • Schoenborn C.A.
        • Loustalot F.
        Trend and prevalence estimates based on the 2008 Physical Activity Guidelines for Americans.
        Am J Prev Med. 2010; 39: 305-313https://doi.org/10.1016/j.amepre.2010.06.006
        • Kraschnewski J.L.
        • Sciamanna C.N.
        • Poger J.M.
        • et al.
        Is strength training associated with mortality benefits? A 15 year cohort study of U.S. older adults.
        Prev Med. 2016; 87: 121-127https://doi.org/10.1016/j.ypmed.2016.02.038
        • Seguin R.
        • Nelson M.E.
        The benefits of strength training for older adults.
        Am J Prev Med. 2003; 25: 141-149https://doi.org/10.1016/S0749-3797(03)00177-6
        • Roddy E.
        • Zhang W.
        • Doherty M.
        Aerobic walking or strengthening exercise for osteoarthritis of the knee? A systematic review.
        Ann Rheum Dis. 2005; 64: 544-548https://doi.org/10.1136/ard.2004.028746
        • Fontaine K.R.
        • Haaz S.
        Risk factors for lack of recent exercise in adults with self-reported, professionally diagnosed arthritis.
        J Clin Rheumatol. 2006; 12: 66-69https://doi.org/10.1097/01.rhu.0000208611.19231.f0
        • Hootman J.M.
        • Macera C.A.
        • Ham S.A.
        • Helmick C.G.
        • Sniezek J.E.
        Physical activity levels among the general U.S. adult population and in adults with and without arthritis.
        Arthritis Rheum. 2003; 49: 129-135https://doi.org/10.1002/art.10911
        • Stone R.C.
        • Baker J.
        Painful choices: a qualitative exploration of facilitators and barriers to active lifestyles among adults with osteoarthritis.
        J Appl Gerontol. 2015; (In press. Online August 27)https://doi.org/10.1177/0733464815602114
        • Wilcox S.
        • Der Ananian C.
        • Abbott J.
        • et al.
        Perceived exercise barriers, enablers, and benefits among exercising and nonexercising adults with arthritis: results from a qualitative study.
        Arthritis Rheum. 2006; 55: 616-627https://doi.org/10.1002/art.22098
        • Iversen M.D.
        • Scanlon L.
        • Frits M.
        • Shadick N.A.
        • Sharby N.
        Perceptions of physical activity engagement among adults with rheumatoid arthritis and rheumatologists.
        Int J Clin Rheumtol. 2015; 10: 67-77https://doi.org/10.2217/ijr.15.3
        • Arnold J.B.
        • Walters J.L.
        • Ferrar K.E.
        Does physical activity increase after total hip or knee arthroplasty for osteoarthritis? A systematic review.
        J Orthop Sports Phys Ther. 2016; 46: 431-442https://doi.org/10.2519/jospt.2016.6449
      4. Bartlett S. Role of Exercise in Arthritis Management. Managing Your Arthritis. www.hopkinsarthritis.org/patient-corner/disease-management/role-of-exercise-in-arthritis-management/. Published 2011. Accessed January 19, 2017.

        • National Center for Health Statistics
        Arthritis, osteoporosis, and chronic back conditions. Healthy People 2020 Midcourse Review.
        National Center for Health Statistics, Hyattsville, MD2016 (Accessed January 13, 2017)
        • Iversen M.D.
        • Fossel A.H.
        • Daltroy L.H.
        Rheumatologist-patient communication about exercise and physical therapy in the management of rheumatoid arthritis.
        Arthritis Care Res. 1999; 12: 180-192https://doi.org/10.1002/1529-0131(199906)12:3<180::AID-ART5>3.0.CO;2-#
        • AuYoung M.
        • Linke S.E.
        • Pagoto S.
        • et al.
        integrating physical activity in primary care practice.
        Am J Med. 2016; 129: 1022-1029https://doi.org/10.1016/j.amjmed.2016.02.008
      5. American College of Sports Medicine (ACSM). Exercise is Medicine. Healthcare Providers׳ Action Guide. http://exerciseismedicine.org/assets/page_documents/Complete%20HCP%20Action%20Guide_2016_01_01.pdf. Accessed May 26, 2016.

      6. CDC. Intervention Programs. Physical Activity Programs. www.cdc.gov/arthritis/interventions/physical-activity.html. Published 2016. Accessed July 25, 2016.

        • Li T.
        • Wei S.
        • Shi Y.
        • et al.
        The dose-response effect of physical activity on cancer mortality: findings from 71 prospective cohort studies.
        Br J Sports Med. 2016; 50: 339-345https://doi.org/10.1136/bjsports-2015-094927
        • Sallis J.F.
        • Saelens B.E.
        Assessment of physical activity by self-report: status, limitations, and future directions.
        Res Q Exerc Sport. 2000; 71: 1-14https://doi.org/10.1080/02701367.2000.11082780
        • Dunlop D.D.
        • Song J.
        • Semanik P.A.
        • et al.
        Objective physical activity measurement in the osteoarthritis initiative: are guidelines being met?.
        Arthritis Rheum. 2011; 63: 3372-3382https://doi.org/10.1002/art.30562
        • White D.K.
        • Tudor-Locke C.
        • Felson D.T.
        • et al.
        Do radiographic disease and pain account for why people with or at high risk of knee osteoarthritis do not meet physical activity guidelines?.
        Arthritis Rheum. 2013; 65: 139-147https://doi.org/10.1002/art.37748
        • Loustalot F.
        • Carlson S.A.
        • Kruger J.
        • Buchner D.M.
        • Fulton J.E.
        Muscle-strengthening activities and participation among adults in the United States.
        Res Q Exerc Sport. 2013; 84: 30-38https://doi.org/10.1080/02701367.2013.762289