Table 5.
Neuromuscular electrical stimulation and magnetic stimulation training.
| Author, year of publication | Number of patients (n) | Mean (SD) FEV1 (%predicted) | Mean (SD) age (y) | Study design | Study intervention | Study duration | Outcome measures | Significant difference within groups post training | Significant change pre to post (% baseline) | Significant difference between groups (% change) |
|---|---|---|---|---|---|---|---|---|---|---|
| Neuromuscular electrical stimulation (NMES) | ||||||||||
| Bourjeily-Habr et al., 200254 | 18 COPD: 9 NMES, 9 control (C) | NMES: 36 (4), C: 41 (4) | NMES: 59 (2), C: 62 (2) | RCT | NMES: 50 Hz for 200 ms every 1500 ms at initial 55 mA–120 mA (intensity increased 5 mA/week) for 20 minutes each limb (quadriceps, hamstrings, and calf muscles). C: no active electrical stimulation | 6 weeks (3x/w) | Maximal quadriceps strength: isokineticb Maximal hamstring strength: isokineticb | NMES (p = 0.004) ns C NMES (p = 0.02) ns C | ↑39% – ↑33.9% – | NMES > C (p = 0.046) NMES > C (p = 0.038) |
| Neder et al., 200255 | 15 COPD: 9 NMES, 6 control first 6 weeks + NMES last 6 weeks (C) | NMES: 38 (10); C: 40 (13) | NMES: 67 (8); C: 65 (5) | RCT | NMES: 50 Hz, pulse width 300–400 µs, 2 seconds on–18 s off (progressed to 10 s on –30 s off) at 10–20 mA (progressed to 100 mA) for 15 minutes each leg (progressed to 30 minutes), quadriceps femoris muscle C: receive NMES after a control period | 6 weeks (5x/w) | Maximal quadriceps strength: isokinetic (70°/second)b Quadriceps strength: isometricb Quadriceps endurance isokinetic: 1 minute maximal number of contractions at angular velocity 70°/second (fatigue index)b | C last 6 weeks (p < 0.05) Not reported NMES ns NMES ns C last 6 weeks C last 6 weeks (p < 0.05) Not reported NMES | ↑e – – – ↓e – | NMES > C (p < 0.05)d ns between groupsd NMES > C (p < 0.05)d |
| Dal Corso et al., 200756 | 17 COPD: assigned to NMES followed by sham or sham followed by NMES | All COPD: 50 (13) | All COPD: 66 (7) | Cross-over RCT (due to no significant effect of treatement sequence all the subjects were seen as a single group) | NMES: 50 Hz, pulse width 400 µs, 2 seconds on–10 seconds off (progressed to 10 seconds on–20 seconds off) at 10 to 25 mA (progressed weekly with 5 mA) for 15 minutes each leg (progressed to 60 minutes), quadriceps femoris muscle. Sham: 10 Hz, pulse width 50 µs at 10 mA for 15 minutes each leg (quadriceps femoris muscle) | 6 weeks (5x/w) | Concentric contraction of quadriceps: isokinetic (60°/second)b Right leg muscle mass (DEXA) | ns ns | – – | – – |
| Napolis et al., 201157 | 30 COPD: assigned to NMES followed by sham or sham followed by NMES | All COPD: 50 (13) | All COPD: 64 (7) | Cross-over RCT | NMES: 50 Hz, 300–400 µs pulse width, 2 seconds on–10 seconds off (progressed to 10 seconds on–20 seconds off) at 15–20 mA (progressed to 60 mA) for 15 minutes each leg (progressed to 60 minutes), quadriceps femoris muscle; Sham: 50 Hz, 200 µs pulse width, 2 seconds on–10 seconds off at 10 mA for 15 minutes each leg (quadriceps femoris muscle) | 6 weeks (5x/w) | Quadriceps strength: isokineticb Quadriceps strength: isometricb | ns NMES ns sham ns NMES ns sham | – – – – | ns between groups Not reported |
| Vivodtzev et al., 201258 | 20 COPD: 12 NMES, 8 sham | NMES: 34 (3) Sham: 30 (4) | NMES: 70 (1) Sham: 68 (3) | RCT | NMES: 50 Hz, 400 µs pulse width, 6 seconds/16 seconds on-off cycle, intensity set at patients tolerance for 35 minutes quadriceps muscle and 25 minutes calf muscle Sham: 5 Hz, 100 µs pulse width | 6 weeks (5x/w) | Quadriceps strength: isometrica Quadriceps endurance: maintain 60% MVC until exhaustion (time to fatigue = time when isometric contraction dropped to 50% MVC)a Midthigh muscle CSA (CT) Calf muscle CSA (CT) | Not reported NMES Not reported sham Not reported NMES Not reported sham Not reported NMES Not reported sham Not reported NMES Not reported sham | ↑11% Not reported ↑37% Not reported ↑6% Not reported ↑6% Not reported | NMES > sham (p < 0.03) NMES > sham (p < 0.03) NMES > sham (p < 0.05) NMES > sham (p < 0.05) |
| Vieira et al., 201459 | 20 COPD: 11 NMES, 9 sham | NMES: 37 (11); Sham: 40 (14) | NMES: 56.3 (11); Sham: 56.4 (13) | RCT | NMES: 50 Hz, 300–400 µs pulse width, 2 seconds on–18 seconds off (progressed to 10 seconds on –30 seconds off) at 15–20 mA (progressed to 100 mA) for 60 minutes twice a day, bilateral quadriceps Sham: no stimulation current | 8 weeks (5x/w) | Thigh circumference (after 4 weeks) | NMES (p < 0.01) ns sham | ↑2.9% – | NMES > sham (p < 0.01)d |
| Maddocks et al., 201660 | 52 COPD: 25 NMES, 27 sham | NMES: 31 (11); Sham: 31 (13) | NMES: 70 (11) Sham: 69 (9) | RCT | NMES: 50 Hz, 350 µs pulse width, 2s/15 seconds on–off (progressed to 10 s on–15 s off) at 0–120 mA (progressed based on patients tolerance) for 30 minutes, bilateral quadriceps muscle Sham: 0–20 mA | 6 weeks (7x/w) | Quadriceps unpotentiated twitch (adjusted for baseline) Quadriceps strength: isometrica Rectus femoris CSA (ultrasound) | NMES (p < 0.05) ns sham NMES (p < 0.05) ns sham NMES (p < 0.05) ns sham | ↑14% – ↑14.8% – ↑19.7% – | NMES > sham (p = 0.045) NMES > sham (p = 0.028) NMES > sham (p = 0.003) |
| Magnetic stimulation training (MST) | ||||||||||
| Bustamante et al., 201061 | 18 COPD: 10 MST, 8 control (C) | MST: 30 (7) C: 35 (8) | MST: 61 (6) C: 62 (8) | RCT | MST: 15 Hz, 2 seconds on, 4 seconds off at intensity 40% (increased by 2–3% every session) for 15 minutes each thigh C: no intervention | 8 weeks (3x/w) | MVC quadriceps: isometrica Quadriceps endurance isometric: maximal sustainable time for leg extensions of the dominant leg bearing 10% of MVC (12 contractions per minute)a Unpotentiated twitch quadriceps | MST (p = 0.005) ns C MST (p = 0.05) ns C ns MST ns C | ↑17.5% – ↑44% – – – | Not reported Not reported Not reported |
ns: not significant; RCT: randomized controlled trial; RM: repetition maximum; FEV1: forced expired volume in 1 second; MVC: maximum voluntary contraction; CSA: cross-sectional area; CT: computed tomography; DEXA: dual energy x-ray absorptiometry.
aMeasured via strain-gauge system.
bMeasured via computerized dynamometer, for example, Biodex.
cMeasured via hand-held dynamometer.
dBetween groups difference based on post training value.
eData not reported.