title: The effects of high-intensity and low-intensity cycle ergometry in older adults with knee osteoarthritis.
abstract: BACKGROUND
  People with osteoarthritis (OA) of the knee experience pain and deconditioning that lead to disability. This study challenged the clinical belief that repetitive lower extremity exercise is not indicated in persons with knee OA. The effects of high-intensity and low-intensity stationary cycling on functional status, gait, overall and acute pain, and aerobic capacity were examined.
  
  
  METHODS
  Thirty-nine adults (71+/-6.9 years old) with complaints of knee pain and diagnosis of OA were randomized to either a high-intensity (70% heart rate reserve [HRR]) or low-intensity (40% HRR) exercise group for 10 weeks of stationary cycling. Participants cycled for 25 minutes, 3 times per week. Before and after the exercise intervention they completed the Arthritis Impact Measurement Scale 2 for overall pain assessment, underwent timed chair rise, 6-minute walk test, gait, and graded exercise treadmill tests. Acute pain was reported daily with a visual analog scale and the Western Ontario and McMaster Universities Osteoarthritis Index scale.
  
  
  RESULTS
  Analysis of variance revealed that participants in both groups significantly improved in the timed chair rise, in the 6-minute walk test, in the range of walking speeds, in the amount of overall pain relief, and in aerobic capacity. No differences between groups were found. Daily pain reports suggested that cycling did not increase acute pain in either group.
  
  
  CONCLUSIONS
  Cycling may be considered as an alternative exercise modality for patients with knee OA. Low-intensity cycling was as effective as high-intensity cycling in improving function and gait, decreasing pain, and increasing aerobic capacity.
authors.affiliation: Department of Physical Therapy, Beaver College, Glenside, Pennsylvania 19038, USA. kline@castle.beaver.edu
authors.forename: K K
authors.initials: KK
authors.lastname: Mangione
authors.forename: K
authors.initials: K
authors.lastname: McCully
authors.forename: A
authors.initials: A
authors.lastname: Gloviak
authors.forename: I
authors.initials: I
authors.lastname: Lefebvre
authors.forename: M
authors.initials: M
authors.lastname: Hofmann
authors.forename: R
authors.initials: R
authors.lastname: Craik
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D000375:Aging; D000704:Analysis of Variance; D001642:Bicycling / Q000502:physiology; D016552:Ergometry; D005080:Exercise Test; D005081:Exercise Therapy; D005260:Female; D005684:Gait / Q000502:physiology; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology*; D008297:Male; D020370:Osteoarthritis, Knee / Q000503:physiopathology / Q000534:rehabilitation*; D010101:Oxygen Consumption / Q000502:physiology; D010146:Pain / Q000503:physiopathology; D010147:Pain Measurement; D011187:Posture / Q000502:physiology; D016138:Walking / Q000502:physiology