Table 1.
Characteristics of the studies included in the review.
| Author/Year | Study Design | Participants Characteristics | Intervention/Rehabilitation Protocol | Pressure (mmHg) | Measure Time Points | Outcome Measures, Units |
|---|---|---|---|---|---|---|
| Ferraz et al., 2018 [25] | RCT | - OA - Women - n = 48 - 3 groups: CG1: HI-RT (80% 1MR) MY: 59.9 ± 4 n = 16 CG2: LI-RT (30% 1MR) MY: 60.7 ± 4 n = 16 IG: LI-RT + BFR (30% 1MR + BFR) MY: 60.3 ± 4 n = 16 |
12 weeks, 2 times per week Bilateral leg press and knee extension exercises - 1st week: HI-RT = 4 × 10 (50%) LI-RT = 4 × 15 (20% 1MR) LI-RT + BFR = 4 × 15 (20% 1MR) - 2nd week: HI = 4 × 10 (80% 1MR) LI = 4 × 15 (30% 1MR) LI-RT + BFR = 4 × 15 (30% 1MR) - 5th week: HI = 5 × 10 (80% 1MR) LI = 5 × 15 (30% 1MR) LI-RT + BFR = 5 × 15 (30% 1MR) 1 rest between sets BFR is kept through exercise and rest |
70% BFR Media: 97.4 ± 7.6 mmHg |
12 weeks | Strength: - 1MR leg press - 1MR knee extension CSA quadriceps: - CT Function: - TST (s) - TUG (s) - Sub scale WOMAC functional capacity (17 items, 0–68 points) Quality of life: - WOMAC (0–100 points) - SF-36 (0–100) Pain: - Sub scale WOMAC pain (5 items, 0–20 points) |
| Harper et al., 2019 [26] | RCT pilot |
- OA - Men and women - n = 35 - 2 groups: CG: MIRT (60% 1MR) n = 19 (15 women and 4 men) MY: 69.1 ± 7.1 IG: BFR (20% 1MR) n = 16 (10 women and 6 men) MY: 67.2 ± 5.2 |
12 weeks, 3 times per week 4 exercises: leg press, leg extension, calf flexion and leg flexion. Repetitions were carried out until muscular fatigue. CG: 60% 1MR IG: 20% 1MR with BFR BFR is kept through exercise and deflates in the rest periods |
Individualized to each patient | 12 weeks | Strength: - isokinetic extensor strength (Nm) Function: - SPPB (0–12 points) - walking speed (m/s) Disability and function: - LLFDI (0-100 points) Pain: - Sub scale of pain WOMAC (0–20) |
| Segal et al., 2015 [28] | RCT | - OA - Women - n = 45 - 2 Groups: CG: low load (30% 1MR) n = 24 MY: 54.6 ± 6.9 IG: BFR + low load n = 21 MY: 56.1 ± 5.9 |
4 weeks, 3 times per week 4 set of bilateral leg press (1× 30 and 3× 15 reps with 30 s rest between sets) CG: 30% 1MR IG: 30% 1MR with BFR Pressure is maintained during exercise and rest (5 min of occlusion during exercise and 1.5 min of rest) |
160–200 mmHg | 4 weeks | Strength - isokinetic bilateral press strength (kg/kg) - max. isokinetic extensor strength (Nm/kg) Pain: - KOOS scale (0–100 points) |
| Segal et al., 2015 [27] | RCT | - OA - Men - n = 42 - 2 groups: CG: low load (30% 1MR) n = 22 MY: 56.1 ± 7.7 IG: BFR + low load n = 20 MY: 58.4 ± 8.7 |
4 weeks, 3 times per week 4 set of bilateral leg press (1× 30 and 3× 15 reps with 30 s rest between sets) CG: 30% 1MR IG: 30% 1MR with BFR Pressure is maintained during exercise and rest (5 min of occlusion during exercise and 1.5 min of rest) |
160–200 mmHg | 4 weeks | Strength: - isokinetic bilateral press strength (kg/kg) - max. isokinetic extensor strength (Nm/kg) Pain: - KOOS scale (0–100 points) |
| Bryk et al., 2016 [29] | RCT | - OA - Women - n = 34 - 2 Groups: CG: heavy load (70% 1MR) n = 17 MY: 60.4 ± 6.7 IG: BFR + low load (30% 1MR) n = 17 MY: 62.3 ± 7.0 |
6 weeks, 3 times per week Strengthening and stretching of LE CG: Quadriceps strengthening 70% 1MR IG: Quadriceps strengthening 30% 1MR with BFR Pressure is held only during exercise |
200 mmHg | 6 weeks | Strength: - MVIC Pain: - NPRS (0–10 cm), 2 measures: 1. Pain intensity 2. Pain during exercise. Function: - Lequesne questionnaire (0–20 points) - TUG (s) |
| Curran et al., 2020 [30] | RCT | - ACL reconstruction - Men (n = 15) and women (n = 19) - n = 34 4 Groups: CG1: concentric n = 8 (3 men and 5 women) MY: 6.1 ± 2.6 G2: eccentric n = 8 (2 men and 5 women) MY: 18.8 ± 3.9 IG1: BFR + concentric n = 9 (5 men and 4 women) MY: 15.3 ± 0.9 IG2: BFR + eccentric n = 9 (5 men and 4 women) MY: 16.0 ± 1.7 Later: 2 groups: CG: non-BFR n = 16 (5 men and 11 women) MY: 17.4 ± 3.5 IG: BFR n = 18 (10 men and 8 women) MY: 15.7 ± 1.3 |
8 weeks, 2 times per week 5 sets of 10 reps 2 min rest between sets. Isokinetic leg press concentric or eccentric 70% 1MR with or without BFR. Training starts 10 weeks after surgery. CG: Heavy load 70% 1MR, concentric or eccentric IG: Heavy load 70% 1MR concentric or eccentric with BFR Pressure is held only during exercise and released during rest and between sets 4 measurements: 1. Pre-operative (2 weeks before surgery) 2. Pre-intervention 3. Post-intervention (2 weeks after finishing the intervention) 4. Return to activity (RTA) |
80% BFR (110–186 mmHg) | 20 weeks | Strength: - Quadriceps MVIC - Quadriceps isokinetic strength - 1MR leg press Function: -IKDC scale (0–100 points) |
| Iversen et al., 2016 [31] | RCT blind | - ACL reconstruction (athletes) - n = 24 subjects - ACL injury with less than 6 months pre-surgery. - 2 groups: CG: exercise n = 12 (7 men and 5 women) MY: 29.8 ± 9.3 IG: BFR + exercise n = 12 (7 men and 5 women) MY: 25.9 ± 7.4 |
2 weeks 5 set of 20 reps quadriceps exercises with or without BFR. IG: bent trunk 45°, 5 reps, 2 times per day. Quadriceps exercise with occlusion (isometric contractions, progressing to knee extension and leg raise with knee straight. 20 reps every 5 min of occlusion. (100 reps per session, 200 per day). Intervention 2 weeks after surgery. CG: Same exercises without BFR Pressure is held during exercise (5 min) and released during rest (3 min) |
130–180 mmHg (first day 130 mmHg. 10 mmHg increase every two days until reaching 180 mmHg) | 16 days post-surgery | Quadriceps CSA: MRI (2 days before surgery and 16 days after surgery) |
| Ohta et al., 2003 [32] | RCT prospective | - ACL with semitendinosus auto graft - n: 44 patients (25 men and 19 women) -Age 18–52 years -2 groups: CG: exercise: n = 22 (12 men and 10 women) MY: 30 ± 9.7 IG: BFR + exercise n = 22 MY: 28 ± 9.7 |
16 weeks Week 1: both groups just exercise Week 2: IG exercise with BFR Exercise: leg raise with knee extension and hip abduction for 5 s 20 reps Exercises twice a day, 6 times per week for 8 weeks after the surgery (weeks 2–4 add 1 kg to the foot; weeks 5–8 add 2 kg Hip adduction exercise (hold ball between two knees) and squat exercise for 5 s 20 reps 2 times per day, 6 times per week. weeks 1–12 post-surgery, 16 weeks post ACL reconstruction. Exercises LE. 1–3 sets × day. 6 times per week. 20–60 reps. 14 weeks (first 2 weeks after surgery without BFR) Occlusion during training for a maximum of 15 min, then rest without inflation for 15–20 min |
180 mmHg | 16 weeks post-surgery | Measurements before and 16 weeks after surgery. Muscle strength: Isokinetic and isometric knee extensors and flexors: Dynamometer CSA of extensor and flexor muscles + adductor muscles: MRI |
| Hughes et al., 2018 [33] | RCT | - ACL with semitendinosus auto graft - n = 30 - Age: 23–39 years (23 men and 7 women) - 3 groups: CG1: No injured BFR + low-load exercise (30% 1MR) (NI-BFR). n = 10 (10 men) MY: 28 ± 5 CG2: ACL surgery with heavy-load exercises (70% 1MR). (ACLR-HL) n = 10 (7 men and 3 women) MY: 31 ± 7 IG: ACL surgery with BFRv+ low-load exercise (30% 1MR) (ACLR-BFR) n = 10 (6 men and 4 women) MY: 29 ± 5 |
Single session 5 min warm-up of pedal stroke followed by 10 reps of one-sided press with self-selected weight and 5 min of rest. ACL patients work on the operated side and patients without ACL work with the dominant limb. NI-BFR (CG1) and ACLR-BFR (IG) did 4 sets (30, 15, 15 and 15 reps, with 30 s rest between sets) unilateral leg press 30% 1MR from 0° to 90° ROM with 1 s concentric/1 s eccentric with BFR 80%. - ACLR-HL group unilateral leg press (3× 10 reps with 30 s rest between sets) form 0°–90° ROM 70% 1MR BFR during exercise and rest |
NI-BFR: 173 mmHG ACLR-BFR: 186 mmHG |
23 days post-surgery | Pain: - Muscular (0–11 points) - Knee: pain scales Muscle pain was evaluated in all 3 groups. Knee pain was evaluated in ACLR-BFR and ACLR-HL groups |
| Hughes et al., 2019 [34] | RCT | - ACL surgery - n: 28 Selected in a previous study (Hughes et al. 2018) - 2 groups: CG: HL-RT heavy load 70% 1MR n = 14 (10 men and 2 women) MY: 29 ± 7 IG: BFR-RT low load (30% 1MR) n = 14 (7 men and 5 women) MY: 29 ± 7 |
8 weeks, 16 sessions, 2 times per week Evaluation to start 48 h after the surgery. Unilateral leg press. Familiarization session with 5 min warm-up with unloaded bike. CG: 3× 10 reps. 30 s rest between sets, unilateral leg press, from 0°–90°, 70% 1M IG: 4 sets (30, 15, 15 and 15 reps) unilateral leg press Both limbs were trained. Occlusion was applied during exercise and rest time. |
- 80% BFR - 150 mmHg operated lower limb - 157 mmHg healthy lower limb |
8 weeks | Pain: - Muscular: Borg scale (last session measurement) - Knee: pain scales. 24 h after the session and during the session. Measurement of the average of the last sessions. |
Abbreviations: RCT, randomized controlled trial; OA, osteoarthritis; ACL, anterior cruciate ligament; ACLR, anterior cruciate ligament reconstruction; BFR, blood flow restriction; 1MR, 1 maximum repetition; MY, mean years; CG, control group; IG, intervention group; HI-RT, high-intensity resistance training; LI-RT, low-intensity resistance training; MRI, magnetic resonance imaging; CT, computed tomography; WOMAC, Western Ontario and McMaster Universities Osteoarthritis Index; TST, timed-stands test; TUG, Timed Up and Go; CSA, quadriceps cross-sectional area; SF-36, Short Form-36 health questionnaire; MIRT, moderate-intensity resistance training; SPPB, Short Physical Performance Battery; LLFDI, Late Life Functional And Disability Instrument; KOOS, Knee Injury and Osteoarthritis Outcome Score; NPRS, Numeric Pain Rating Scale; MVIC, maximum voluntary isometric contraction; IKDC, International Knee Documentation Committee; SEBT, star excursion balance test; LE, lower extremity; BFR-RE, blood flow restriction resistance exercise; NI-BFR, non-injured BFR-RE; ACLR-BFR, ACLR patients’ blood flow restriction resistance exercise; ACLR-HL, ACLR patients heavy-load resistance exercise; ROM, range of motion; BFR-RT, blow flow restriction resistance training; HL-RT, heavy-load resistance training.