Effects of Intermittent Versus Continuous Blood Flow Restriction Training on Pain, Functional Ability, Muscle Strength and Exercise Perception Among Female Patients With Grade II Knee Osteoarthritis

NCT07722975 | Completed DMC

• 1 other identifier: UBAS/ERB/26/04/012
• Study Type: interventional
• Target: 84
• Locations: 1 country
• Sites: 1

Brief Summary

This study holds significant clinical, academic, and practical importance in the field of musculoskeletal rehabilitation. Clinically, it addresses a critical need to identify an effective and tolerable strengthening strategy for females with early-stage knee osteoarthritis. By directly comparing intermittent and continuous BFR protocols, the findings will provide physiotherapists with evidence-based guidance for optimizing exercise prescription while minimizing discomfort and improving adherence.Academically, this research contributes to the limited body of literature comparing different BFR application strategies in knee osteoarthritis. The inclusion of exercise perception outcomes adds valuable insight into patient-centered rehabilitation, which is often underrepresented in clinical trials.From a practical and societal perspective, identifying a more tolerable BFR approach may enhance long-term exercise participation, delay disease progression, and reduce healthcare burden associated with knee osteoarthritis. The findings may also support the integration of low-load BFR training into rehabilitation programs in resource-limited clinical settings.

Conditions

Knee Osteoarthristis

Keywords

Blood Flow Restriction (BFR); Intermittent BFR; Continuous BFR; Exercise Perception; Functional Ability

Outcome Measures

Primary Outcomes (3)

• Manual Muscle Testing (MMT)

  Quadriceps strength will be assessed using standardized isometric testing procedure. It grades muscle strength on a 0-5 scale based on the ability to move a joint against gravity and external resistance. A grade of 0 indicates no visible or palpable muscle contraction, while 1 (Trace) represents a slight contraction without actual movement. Grade 2 (Poor) describes the ability to move the joint through its full range only when gravity is eliminated, whereas Grade 3 (Fair) allows movement through the full range against gravity but without resistance. Grade 4 (Good) indicates movement against moderate resistance, and Grade 5 (Normal) reflects full range of motion against maximal resistance, representing normal muscle strength

  baseline, 6 weeks (post intervention), 12 weeks (follow up)

• Numeric Pain Rating Scale (NPRS)

  The NPRS is a10-point scale (0-10) used to quantify pain intensity. Pain severity will be interpreted as no pain (0), mild pain (1-3), moderate pain (4-6), and severe pain (7-10).

  baseline, 6 weeks (post intervention), 12 weeks( followup)

• Modified Borg Scale

  It is used to assess ratings of exercise-related perceived exertion. The scale ranges from (0 to 10), where 0 means no breathlessness at all and 10 means maximium breathlessness. According to this, 0-2 for Minimal exertion, 3-4 for Moderate (often target for rehab), 5-6 for Hard and 7-10 is for Very hard to maximal

  baseline, 6 weeks( post intervention), 12 weeks (follow up)

Study Arms (2)

Intermittent blood flow

EXPERIMENTAL

Participants will perform low-load resistance exercises at 20-30% of one-repetition maximum (1RM) combined with intermittent BFR application. Cuff pressure will be applied during exercise sets and released during rest intervals. Each session will include a 10-minute warm-up , followed by a 30-minute structured exercise program and a 15-minute cool-down. Sessions will be conducted 2-3 times per week for a duration of 8-12 weeks, with progressive overload applied as tolerated.

Other: Intermittent blood flow training (iBFR)

Continuous blood flow training

EXPERIMENTAL

Participants will perform the same low-load resistance exercise protocol (20-30% 1RM) with continuous BFR application. Cuff pressure will be maintained throughout both exercise and rest periods. Exercise selection, session structure (warm-up, training, cool-down), frequency (2-3 sessions/week), and duration (8-12 weeks) will be identical to Group A to ensure comparability between groups

Other: Continuous blood flow training (cBFR)

Interventions

Continuous blood flow training (cBFR) OTHER

Hamstrings stretching, 3 repetitions of 30 s, Bridge with isometric contraction of the transversus abdominis-CORE training, 3 repetitions of 30 s, Hip abduction with weights (side lying), 3 sets of 10 repetitions, Calm exercises (side lying) with an elastic band, 3 sets of 10 repetitions, Calf raises with weights (standing), 3 sets of 10 repetitions, Sensori motor training (standing) at mini-trampoline, 3 repetitions of 30 s, Leg press (machine), 0-60°, 4 sets of 10 repetitions, Seated knee extension, 90-0° of knee flexion, 4 sets of 10 repetitions. In the cBFR group, the Intensity of excersise will be 20-30% of 1RM with BFR cuffs ,Frequency: 3 sessions per week for 12 weeks. Each session comprises a 10-min warmup with static cycling, a 30-min exercise program, and a 15-min cool down. BFR cuff from Hhccteo company will be used. The parameters will be pressure: 130-150 mmHg, cuff width 5-7 cm. Progressive overload will be applied by gradually increasing repetitions or load as tolerated

Continuous blood flow training

Intermittent blood flow training (iBFR) OTHER

Hamstrings stretching, 3 repetitions of 30 s, Bridge with isometric contraction of the transversus abdominis-CORE training, 3 repetitions of 30 s, Hip abduction with weights , 3 sets of 10 repetitions, Calm exercises with an elastic band, 3 sets of 10 repetitions, Calf raises with weights , 3 sets of 10 repetitions, Sensori-motor training at mini-trampoline, 3 repetitions of 30 s, Leg press, 0-60°, 4 sets of 10 repetitions, Seated knee extension , 90-0° of knee flexion, 4 sets of 10 repetitions. In the iBFR group, the cuff is deflated during each set's rest period and is quickly reinflated to the target pressure 20-30 s into the rest, ensuring the entire rest period does not exceed 45 s . Intensity: 20- 30% of 1RM with BFR cuffs, Frequency: 3 sessions per week for 12 weeks. Each session comprises a 10-min warm up with static cycling, a 30-min exercise program, and a 15-min cool down. BFR cuff from Hhccteo company will be used. pressure:130-150 mmHg, cuff width 5-7cm

Intermittent blood flow

Eligibility Criteria

• Age: 40 Years - 49 Years
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Female patients aged 40-49 years.
• Diagnosed with Grade II knee osteoarthritis (radiographically confirmed).
• Moderate to severe pain (NPRS 4-7).
• Ability to participate in exercise programs.

You may not qualify if:

• Severe cardiovascular disease.
• Uncontrolled hypertension.
• Recent knee surgery or intra-articular injection.
• Active cancer or metastatic disease

Sponsors & Collaborators

• Lahore University of Biological and Applied Sciences: lead

Study Sites (1)

Social Security Hospital, Lahore

Lahore, Punjab Province, 05450, Pakistan

Location

Related Publications (5)

• Freitas EDS, Miller RM, Heishman AD, Aniceto RR, Silva JGC, Bemben MG. Perceptual responses to continuous versus intermittent blood flow restriction exercise: A randomized controlled trial. Physiol Behav. 2019 Dec 1;212:112717. doi: 10.1016/j.physbeh.2019.112717. Epub 2019 Oct 17.

  PMID: 31629764 BACKGROUND

• Harper SA, Roberts LM, Layne AS, Jaeger BC, Gardner AK, Sibille KT, Wu SS, Vincent KR, Fillingim RB, Manini TM, Buford TW. Blood-Flow Restriction Resistance Exercise for Older Adults with Knee Osteoarthritis: A Pilot Randomized Clinical Trial. J Clin Med. 2019 Feb 21;8(2):265. doi: 10.3390/jcm8020265.

  PMID: 30795545 BACKGROUND

• Sorensen B, Aagaard P, Hjortshoj MH, Hansen SK, Suetta C, Couppe C, Magnusson SP, Johannsen FE. Physiological and clinical effects of low-intensity blood-flow restricted resistance exercise compared to standard rehabilitation in adults with knee osteoarthritis-Protocol for a randomized controlled trial. PLoS One. 2023 Dec 14;18(12):e0295666. doi: 10.1371/journal.pone.0295666. eCollection 2023.

  PMID: 38096198 BACKGROUND

• Centner C, Wiegel P, Gollhofer A, Konig D. Effects of Blood Flow Restriction Training on Muscular Strength and Hypertrophy in Older Individuals: A Systematic Review and Meta-Analysis. Sports Med. 2019 Jan;49(1):95-108. doi: 10.1007/s40279-018-0994-1.

  PMID: 30306467 BACKGROUND

• Hughes L, Paton B, Rosenblatt B, Gissane C, Patterson SD. Blood flow restriction training in clinical musculoskeletal rehabilitation: a systematic review and meta-analysis. Br J Sports Med. 2017 Jul;51(13):1003-1011. doi: 10.1136/bjsports-2016-097071. Epub 2017 Mar 4.

  PMID: 28259850 BACKGROUND

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Masking Details: outcome assessor will be blind about participants allocation; this will ensure that their evaluations are objective and not influenced by knowledge of which treatment group participants belong to. Participants in both groups will be masked to the treatment of the other group by scheduling their sessions at different times
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: This study will use a parallel-group randomized controlled design, with participants randomly allocated into two intervention groups. Group A (Intermittent Blood Flow Restriction - iBFR): participants will perform low-load resistance exercises (20-30% 1RM) with BFR cuffs (130-150 mmHg) applied during exercise and released during rest intervals. Group B (Continuous Blood Flow Restriction - cBFR): participants will perform the same exercise protocol with cuff pressure maintained throughout both exercise and rest periods. Both groups will receive identical exercise programs including leg press, knee extension, hip abduction, calf raises, and core exercises, along with standard physiotherapy care. Sessions will be conducted 2-3 times per week for 8-12 weeks. Participants will be randomly assigned into two parallel groups without crossover to ensure unbiased comparison of outcomes.

Study Record Dates

• First Submitted: July 20, 2026
• First Posted: July 23, 2026
• Study Start: May 1, 2026
• Primary Completion: July 10, 2026
• Study Completion: July 20, 2026
• Last Updated: July 23, 2026

Record last verified: 2026-07

Data Sharing

• IPD Sharing: Will not share

Locations

PA (1)