This trial is active, not recruiting.

Conditions knee osteoarthritis, symptomatic knee osteoarthritis
Treatments partial blood flow restriction (pbfr), low intensity resistance training
Sponsor University of Iowa
Collaborator The American Geriatrics Society
Start date September 2011
End date November 2011
Trial size 45 participants
Trial identifier NCT01440972, 201109738


The purpose of this study is to asses the efficacy of a 4 week low-intensity resistance training program with concurrent application of partial blood flow restriction (PBFR) to the exercising limbs to improve quadriceps strength and size, leg muscle power, and mobility in women at risk for developing symptomatic knee osteoarthritis. The primary outcome will be change in isotonic double leg-press 1 repetition maximum (1RM) strength. The investigators will test the following hypotheses. In comparison with low-intensity resistance training without use of PBFR, a four-week low-intensity resistance-training program with PBFR will:

Primary Hypothesis: Increase (a) double leg-press 1RM strength and (b) isokinetic knee extensor strength

Secondary Hypotheses:

1. Increase quadriceps muscle volume assessed by MRI

2. Increase lower limb muscle power on (a) double leg-press at 40% 1RM and (b) a timed stair climb

3. Not adversely effect knee pain or quality of life assessed by the Knee injury and Osteoarthritis Outcome Score (KOOS) questionnaire

United States No locations recruiting
Other countries No locations recruiting

Study Design

Allocation randomized
Endpoint classification efficacy study
Intervention model parallel assignment
Masking double blind (subject, investigator, outcomes assessor)
(Active Comparator)
low intensity resistance training
low intensity resistance training without partial blood flow restriction
partial blood flow restriction (pbfr)
low intensity resistance training with partial blood flow restriction 3 times/week for 4 weeks.

Primary Outcomes

Change in isotonic double leg-press 1 repetition maximum strength
time frame: pre-intervention, post-intervention

Secondary Outcomes

Change in quadriceps muscle volume by magnetic resonance imaging
time frame: 4 weeks
Change in lower limb muscle power by a) double leg-press at 40% 1 repetition maximum and b) timed stair climb
time frame: 4 weeks
Change in Knee Injury and Osteoarthritis Outcome Score Pain and Quality of Life subscales
time frame: 4 weeks
Change in isokinetic knee extensor strength
time frame: 4 weeks

Eligibility Criteria

Female participants from 45 years up to 65 years old.

Inclusion Criteria: - Female - Age 45-65 - BMI greater than or equal to 25 kg/m2, or a history of a knee joint injury or surgery, or knee symptoms (pain, aching, or stiffness) on most of the last 30 days, or knee osteoarthritis Exclusion Criteria: - Resistance training at any time in the last 3 months prior to study - Bilateral knee replacement - Lower limb amputation - Lower limb surgery in the last 6 months that affects walking ability or ability to exercise - Back, hip or knee problems that affect walking ability or ability to exercise - Unable to walk without a cane or walker - Inflammatory joint or muscle disease such as rheumatoid or psoriatic arthritis or polymyalgia rheumatica - Multiple sclerosis - Known neuropathy - Self-report of Diabetes - Currently being treated for cancer or having untreated cancer - Terminal illness (cannot be cured or adequately treated and there is a reasonable expectation of death in the near future) - Peripheral Vascular Disease - History of myocardial infarction or stroke in the last year - History of deep venous thrombosis - Chest pain during exercise or at rest - Use of supplemental oxygen - Inability to follow protocol (e.g. lack of ability to attend visits or understand instructions) - Staff concern for subject health (such as history of dizziness/faintness or current restrictions on activity) - Concurrent study participation (such as the MOST study) - Unable to attend more than 2 days within any 1 week or unable to attend 4 or more sessions during the study

Additional Information

Official title Assessment of Efficacy of Low Intensity Resistance Training in Women at Risk for Symptomatic Knee Osteoarthritis
Trial information was received from ClinicalTrials.gov and was last updated in December 2011.
Information provided to ClinicalTrials.gov by University of Iowa.