Protocols aiming to increase muscle mass in persons with motor complete spinal cord injury: a systematic review

Figures & data

Figure 1. Flowchart of study selection procedure (PRISMA).

Table 1. Neuromuscular electrical stimulation-based interventions (n = 13).

Author	Year	Study design (quality)	N	Sex	Age	SCI level	TSI (y)	Measure	Change in SMM/LSTM (IG only)
Studies using neuromuscular electrical stimulation with resistance
Gorgey et al. [33]	2013	RCT (Level 1)	7	M	25–45	C5-T7	>1	MRI	Sartorius: *↑ 46% Adductors: *↔ 20.1% Gracilis: ↔ 15% Hip flexor: ↔ 0.4% Back extensor: ↔ −2.8%
Gorgey et al. [15]	2012	RCT (Level 1)	9	M	35 (mean)	C5-T11	2–26	MRI [DXA]	Quadriceps: *↑ 35% Whole thigh: *↑ 28% Hamstrings: *↑ 16% [Leg: ↔ 10%] [Whole body: ↔ 1%] [Trunk: ↔ 4%]
Ryan et al. [44]	2013	Uncontrolled intervention (Level 3)	14	M (11); F (3)	28–57	C4-T7	2–22	MRI [DXA]	Quadriceps: ↑ 39% Hamstrings: ↔ 7% [Thigh: ↔ 10%]
Gorgey & Shepherd [41]	2010	Case report (Level 4)	1	M	22	C5/6	5	MRI	Right quadriceps: 43% Right adductors: 40% Right sartorius: 38% Right whole thigh: 30% Right gracilis: 20.5% Right hamstrings: 12%
Mahoney et al. [42]	2005	Uncontrolled intervention (Level 4)	5	M	36 (mean)	C5-T10	13	MRI	Left quadriceps: ↑ 38.4% Right quadriceps: ↑ 35%
Gorgey et al. [43]	2017	Within-subject controlled design (Level 4)	5	M	18–49	C6-T11	2–15	MRI	Quadriceps: *↑ 18% Hip adductor: *↑ 13% Whole thigh: *↑ 11% Hamstrings: *↑ 3.5%
Gerrits et al. [45]	2003	Uncontrolled intervention (Level 4)	6	M (5); F (1)	29–56	C5-T9	12	Biopsy	Vastus lateralis: ↔ 9.8%
Gorgey et al. [10]	2016	Case-report (Level 4)	1	M	33	T6	12	DXA	Left leg: 9% Right leg: 4%
Studies using neuromuscular electrical stimulation without resistance
Kern et al. [46]	2005	Case report (Level 4)	1	M	47	T12	1	CT scan	Right quadriceps: 60.8% Left quadriceps: 45.1%
Bogie et al. [49]	2000	Case report (Level 4)	1	M	42	C4	21	CT scan	Right glutaeal: 50% Left glutaeal: 44%
Legg Ditterline et al. [50]	2020	Uncontrolled intervention (Level 4)	6	M (5); F (1)	24–43	C4-C6	3–10	DXA	Legs: ↑ 9% Whole body: ↔ 5%
Erickson et al. [47]	2017	Uncontrolled intervention (Level 4)	14	M (10); F (4)	30–63	C4-T9	13 (mean)	MRI	Right quadriceps: ↔ 6% Left quadriceps: ↔ 1.1%
Martin et al. [48]	1992	Uncontrolled intervention (Level 4)	5	M (3); F (2)	22–38	C6-T4	2–11	Biopsy	Tibialis anterior: 0.7%

C: cervical; CT: computed tomography; DXA: dual x-ray absorptiometry; F: female; IG: intervention group; LSTM: lean soft tissue mass; M: male; MRI: magnetic resonance imaging; RCT: randomised controlled trial; SCI: spinal cord injury; SMM: skeletal muscle mass; T: thoracic; TSI: time since injury.

↑ = significantly increased from baseline (p < 0.05); ↔ = did not change from baseline (p > 0.05); * = significantly higher in the intervention group compared to control group post-intervention (p < 0.05).

Table 2. Functional electrical stimulation cycling-based interventions (n = 14).

Author	Year	Study design (quality)	N	Sex	Age	SCI level	TSI (y)	Measure	Change in SMM / LSTM
Farkas et al. [59]	2021	RCT (Level 1)	13	M (9); F (4)	39 (mean)	T4-T10	NR	DXA	Whole body: ↔ 4.3% Arms: ↔ 1.3% Legs: ↔ 7.4%
Sköld et al. [53]	2002	RCT (Level 2)	15	M	21–48	NR	1–21	DXA	Whole body: ↑ 10%
Gorgey et al. [57]	2016	Longitudinal (Level 2)	9	M	29–61	C5-T10	2–26	DXA	Whole body: ↔ 4.3%
Chilibeck et al. [11]	1999	Longitudinal (Level 3)	6	M (5); F (1)	31–50	C5-T8	3–25	Biopsy	Vastus lateralis: ↑ 23%
Johnston et al. [56]	2016	Uncontrolled intervention (Level 3)	17	M (14); F (3)	23–68	C4-T6	1–27	MRI	Thigh: ↑ 20.4% (20 RPM) Thigh: ↑ 10.7% (50 RPM)
Crameri et al. [14]	2002	Uncontrolled intervention (Level 4)	6	M (5); F (1)	28–43	T4-T12	8–35	Biopsy	Vastus lateralis: 129%
Johnston et al. [55]	2015	Case report (Level 4)	1	M	56	T4	4	MRI	Thigh: 18.9%
Mohr et al. [51]	1997	Uncontrolled intervention (Level 4)	10	M (8); F (2)	27–45	C6-T4	3–23	MRI	Thigh: ↑ 12.1%
Dolbow et al. [60]	2011	Case report (Level 4)	1	M	64	C5	1.5	DXA	Whole body: 8.3%
Dolbow et al. [62]	2014	Case report (Level 4)	1	F	60	T6	2	DXA	Whole body: 7.7% Leg: 4.1%
Dolbow et al. [61]	2012	Case report (Level 4)	1	M	53	C4	33	DXA	Leg: 7.1% Whole body: 3.3%
Dolbow & Credeur [54]	2017	Case report (Level 4)	1	F	31	T10	11	DXA	Leg: 5.3% Whole body: 2.8%
Hjeltnes et al. [52]	1997	Uncontrolled intervention (Level 4)	5	M	28–44	C5-C7	4–23	DXA [CT scan]	Legs: ↑ 4.3% Whole body: ↑ 3% Trunk: ↔ 2.4% [Quadriceps: ↑ 38%] [Gluteus maximus: ↑ 27%] [Hamstrings: ↑ 17%]
Gorgey et al. [58]	2012	Case report (Level 4)	1	M	29	T6	NR	DXA	Whole body: 2%

C: cervical; CT: computed tomography; DXA: dual X-ray absorptiometry; F: female; LSTM: lean soft tissue mass; M: male; MRI: magnetic resonance imaging; NR: not reported; RCT: randomised control trial; SCI: spinal cord injury; SMM: skeletal muscle mass; T: thoracic; TSI: time since injury; RPM: revolutions per minute.

↑ = significantly increased from baseline (p < 0.05); ↔ = did not change from baseline (p > 0.05).

Table 3. Standing and walking-based interventions (n = 8).

Author	Year	Study design (quality)	N	Sex	Age	SCI level	TSI (y)	Measure	Change in SMM / LSTM
de Abreu et al. [12]	2008	RCT (Level 2)	15	M	32 (mean)	C4-C7	2–15	MRI	Quadriceps: ↑ 15.1%
Adams et al. [63]	2006	Case report (Level 4)	1	F	27	C4	5	Biopsy	Vastus lateralis: 27.1%
Beck et al. [64]	2020	Case report (Level 4)	1	M	37	T3	>3	DXA	Whole body: 17.2% (0–6 months) −3.7% (6–12 months)
Terson de Paleville et al. [66]	2019	Case series (Level 4)	4	M	22–31	C5-T5	2 (mean)	DXA	Whole body: 7%
Karelis et al. [67]	2017	Uncontrolled intervention (Level 4)	5	M (4); F (1)	60 (mean)	C7-T10	8 (mean)	DXA [CT scan]	Leg: ↔ 6.7% Appendicular: ↔ 4.7% Trunk: ↔ 3% Whole body: ↔ 1.7% Arm: ↔ 1.1% [Calf: ↔ 16.2%]
Forrest et al. [65]	2008	Case report (Level 4)	1	M	25	C6	1	DXA	Whole body: 5.7% Arms: 1.9% Legs: 10.4% Trunk: 4.5%
Masani et al. [69]	2014	Case series (Level 4)	7	M	24–58	T3-T6	3–29	CT scan	Calf area: ↔ 1.6% Calf density: ↔ 1.2%
Asselin et al. [68]	2021	Uncontrolled intervention (Level 4)	8	M (7); F (1)	34–61	C8-T11	1–14	DXA	Whole body: ↔ 1.0% Arms: ↔ −1.2% Legs: ↔ 1.4% Trunk: ↔ 0.4%

BWSTT: body weight supported treadmill training; C: cervical; CT: computed tomography; DXA: dual x-ray absorptiometry; F: female; LSTM: lean soft tissue mass; M: male; MRI: magnetic resonance imaging; NR: not reported; P: phase; RCT: randomised controlled trial; SCI: spinal cord injury; SMM: skeletal muscle mass; T: thoracic; TSI: time since injury.

↑ = significantly increased from baseline (p < 0.05); ↔ = did not change from baseline (p > 0.05).

Table 4. Pharmacological interventions (n = 3).

Author	Year	Study design (quality)	N	Sex	Age	SCI level	TSI (y)	Measure	Change in SMM / LSTM
Gorgey et al. [70]	2017	Case report (Level 4)	2	M	30–31	T4-T6	4–5	MRI	Right quadriceps: 14% Right thigh: 12.5% Left quadriceps: 10.5% Left thigh: 9%
Gorgey et al. [71]	2019	Case report (Level 4)	1	M	31	T5	7	MRI [DXA]	Thigh: 9% [Whole body: 7.2%]
Halstead et al. [72]	2010	Longitudinal (Level 4)	10	M	23–50	C5-C8	2–26	DXA	Arms: ↔ 5.4% Whole body: ↑ 1.8%

C: cervical; DXA: dual X-ray absorptiometry; LSTM: lean soft tissue mass; M: male; MRI: magnetic resonance imaging; SCI: spinal cord injury; SMM: skeletal muscle mass; T: thoracic; TSI: time since injury.

↑ = significantly increased from baseline (p < 0.05); ↔ = did not change form baseline (p > 0.05).

Table 5. Mixed modality interventions (n = 12).

Author	Year	Study design (quality)	N	Sex	Age	SCI level	TSI (y)	Measure	Change in SMM / LSTM
Holman & Gorgey [35]	2019	RCT (Level 1)	22	M	36 (mean)	C5-T11	9	MRI: TRT + RT vs. TRT	Quadriceps: ↑ 30.8% vs. ↔ % NR
Gorgey et al. [37]	2020	RCT (Level 1)	22	M	36 (mean)	C5-T11	9	Biopsy: TRT + RT vs. TRT	Vastus lateralis: *↑ 27.5% vs. ↔ −9%
Menendez et al. [76]	2016	RCT (Level 1)	17	M (12); F (5)	31–68	C4-T12	4–29	US (Intervention group only)	Left gastrocnemius lateralis: ↑ 22% Right gastrocnemius lateralis: *↑ 18% Right gastrocnemius medialis: ↑ 17% Left gastrocnemius medialis: *↑ 8%
Gorgey et al. [36]	2020	RCT (Level 1)	22	M	36 (mean)	C5-T11	9	MRI: TRT + RT vs. TRT	Glutaeals: ↑ 13.4% vs. ↔ 2.3% Trunk: ↔ 4.9% vs. ↔ −0.7% Lower leg: ↔ −0.2% vs. 2.2%
Gorgey et al. [34]	2019	RCT (Level 1)	22	M	36 (mean)	C5-T11	9	DXA: TRT + RT vs. TRT	Legs: *↑ 12.9% vs. ↔ −1.3% Arms: ↑ 8.2% vs. ↔ 4.2% Whole body: *↑ 5.3% vs. ↔ 1.2% Trunk: *↑ 5.3% vs. ↔ 1.2%
Yarar-Fisher et al. [78]	2018	Uncontrolled intervention (Level 2)	11	M (10); F (1)	36–50	C5-T12	10–30	DXA: EG vs. PG [Biopsy]: EG vs. PG	Whole body: ↔ 1.5% vs. ¯ −2.7% Leg: ↔ 7.9% vs. ↔ −2.1% [Vastus lateralis: ↑ % NR vs. ↔ % NR]
Kern et al. [40]	2005	Uncontrolled intervention (Level 4)	9	M (8); F (1)	20–49	L spine	NR	Biopsy	Vastus lateralis: 151%
Crameri et al. [39]	2004	Within-subject controlled design (Level 4)	6	NR	26–54	C6-T7	3–21	Biopsy: NMES vs. FES	Vastus lateralis: ↑119% vs. ↔ 18.4%
Deley et al. [75]	2015	Case report (Level 4)	1	F	36	T4/5	2	US	Quadriceps: 83% (0–3 months) 136% (0–12 months)
Murphy et al. [38]	1999	Crossover (Level 4)	3	NR	26–48	C6-T4	9–23	Biopsy	Vastus lateralis: 63.4%
Scremin et al. [73]	1999	Uncontrolled intervention (Level 4)	13	M	24–46	C5-L1	2–15	CT scan	Vastus lateralis: ↑ 39% Rectus femoris: ↑ 31% Vastus medialis: ↑ 31% Hamstrings: ↑ 26% Sartorius: ↑ 22%
Frotzler et al. [74]	2008	Longitudinal (Level 4)	11	M (9); F (2)	27–56	T3-T9	3–25	CT scan	Thigh: ↑ 33% (0–6 months) ↑ 34% (0–12 months) ↔ 1% (6–12 months) Tibia: ↔ 7% (0–6 months) ↔ 8% (0–12 months) ↔ 1% (6–12 months)

ACE: arm crank ergometry; C: cervical; CT: computed tomography; DXA: dual X-ray absorptiometry; EG: exercise group; F: female; FES: functional electrical stimulation; L: lumbar; LSTM: lean soft tissue mass; M: male; MRI: magnetic resonance imaging; NMES: neuromuscular electrical stimulation; NR: not reported; PG: protein group; RCT: randomised control trial; RT: resistance training; SCI: spinal cord injury; SMM: skeletal muscle mass; T: thoracic; TRT: testosterone replacement therapy; TSI: time since injury; US: ultrasound.

↑ = significantly increased from baseline (p < 0.05); ↔ = did not change from baseline (p > 0.05); ¯ = significantly decreased from baseline (p < 0.05); * = Significantly greater compared to the control group post-intervention (p < 0.05).

Gorgey AS, Dolbow DR, Cifu DX, et al. Neuromuscular electrical stimulation attenuates thigh skeletal muscles atrophy but not trunk muscles after spinal cord injury. J Electromyogr Kinesiol. 2013;23(4):977–984.

 PubMed Web of Science ®Google Scholar

Gorgey AS, Mather KJ, Cupp HR, et al. Effects of resistance training on adiposity and metabolism after spinal cord injury. Med Sci Sports Exerc. 2012;44(1):165–174.

 PubMed Web of Science ®Google Scholar

Ryan TE, Brizendine JT, Backus D, et al. Electrically induced resistance training in individuals with motor complete spinal cord injury. Arch Phys Med Rehabil. 2013;94(11):2166–2173.

 PubMed Web of Science ®Google Scholar

Gorgey AS, Shepherd C. Skeletal muscle hypertrophy and decreased intramuscular fat after unilateral resistance training in spinal cord injury: case report. J Spinal Cord Med. 2010;33(1):90–95.

 PubMed Web of Science ®Google Scholar

Mahoney ET, Bickel CS, Elder C, et al. Changes in skeletal muscle size and glucose tolerance with electrically stimulated resistance training in subjects with chronic spinal cord injury. Arch Phys Med Rehabil. 2005;86(7):1502–1504.

 PubMed Web of Science ®Google Scholar

Gorgey AS, Lester RM, Wade RC, et al. A feasibility pilot using telehealth videoconference monitoring of home-based NMES resistance training in persons with spinal cord injury. Spinal Cord Ser Cases. 2017;3(1):17039.

 PubMedGoogle Scholar

Gerrits HL, Hopman MTE, Offringa C, et al. Variability in fibre properties in paralysed human quadriceps muscles and effects of training. Pflugers Arch. 2003;445(6):734–740.

 PubMed Web of Science ®Google Scholar

Gorgey AS, Caudill C, Khalil RE. Effects of once weekly NMES training on knee extensors fatigue and body composition in a person with spinal cord injury. J Spinal Cord Med. 2016;39(1):99–102.

 PubMed Web of Science ®Google Scholar

Kern H, Salmons S, Mayr W, et al. Recovery of long-term denervated human muscles induced by electrical stimulation. Muscle Nerve. 2005;31(1):98–101.

 PubMed Web of Science ®Google Scholar

Bogie KM, Reger SI, Levine SP, et al. Electrical stimulation for pressure sore prevention and wound healing. Assist Technol. 2000;12(1):50–66.

 PubMed Web of Science ®Google Scholar

Legg Ditterline B, Harkema SJ, Willhite A, et al. Epidural stimulation for cardiovascular function increases lower limb lean mass in individuals with chronic motor complete spinal cord injury. Exp Physiol. 2020;105(10):1684–1691.

 PubMed Web of Science ®Google Scholar

Erickson ML, Ryan TE, Backus D, et al. Endurance neuromuscular electrical stimulation training improves skeletal muscle oxidative capacity in individuals with motor-complete spinal cord injury. Muscle Nerve. 2017;55(5):669–675.

 PubMed Web of Science ®Google Scholar

Martin TP, Stein RB, Hoeppner PH, et al. Influence of electrical stimulation on the morphological and metabolic properties of paralyzed muscle. J Appl Physiol. 1992;72(4):1401–1406.

 PubMed Web of Science ®Google Scholar

Farkas GJ, Gorgey AS, Dolbow DR, et al. Energy expenditure, cardiorespiratory fitness, and body composition following arm cycling or functional electrical stimulation exercises in spinal cord injury: a 16-week randomized controlled trial. Top Spinal Cord Inj Rehabil. 2021;27(1):121–134.

 PubMed Web of Science ®Google Scholar

Sköld C, Lönn L, Harms-Ringdahl K, et al. Effects of functional electrical stimulation training for six months on body composition and spasticity in motor complete tetraplegic spinal cord-injured individuals. J Rehabil Med. 2002;34(1):25–32.

 PubMed Web of Science ®Google Scholar

Gorgey AS, Graham ZA, Bauman WA, et al. Abundance in proteins expressed after functional electrical stimulation cycling or arm cycling ergometry training in persons with chronic spinal cord injury. J Spinal Cord Med. 2017;40(4):439–448.

 PubMed Web of Science ®Google Scholar

Chilibeck PD, Jeon J, Weiss C, et al. Histochemical changes in muscle of individuals with spinal cord injury following functional electrical stimulated exercise training. Spinal Cord. 1999;37(4):264–268.

 PubMed Web of Science ®Google Scholar

Johnston TE, Marino RJ, Oleson CV, et al. Musculoskeletal effects of 2 functional electrical stimulation cycling paradigms conducted at different cadences for people with spinal cord injury: a pilot study. Arch Phys Med Rehabil. 2016;97(9):1413–1422.

 PubMed Web of Science ®Google Scholar

Crameri RM, Weston A, Climstein M, et al. Effects of electrical stimulation-induced leg training on skeletal muscle adaptability in spinal cord injury. Scand J Med Sci Sports. 2002;12(5):316–322.

 PubMed Web of Science ®Google Scholar

Johnston TE, Marino RJ, Oleson CV, et al. Cycling with functional electrical stimulation before and after a distal femur fracture in a man with paraplegia. Top Spinal Cord Inj Rehabil. 2015;21(4):275–281.

 PubMedGoogle Scholar

Mohr T, Andersen JL, Biering-Sørensen F, et al. Long term adaptation to electrically induced cycle training in severe spinal cord injured individuals. Spinal Cord. 1997;35(1):1–16.

 PubMed Web of Science ®Google Scholar

Dolbow DR, Gorgey AS, Cifu DX, et al. Feasibility of home-based functional electrical stimulation cycling: case report. Spinal Cord. 2012;50(2):170–171.

 PubMed Web of Science ®Google Scholar

Dolbow DR, Gorgey AS, Gater DR, et al. Body composition changes after 12 months of FES cycling: case report of a 60-year-old female with paraplegia. Spinal Cord. 2014;52(S1):S3–S4.

 PubMedGoogle Scholar

Dolbow DR, Gorgey AS, Moore JR, et al. Report of practicability of a 6-month home-based functional electrical stimulation cycling program in an individual with tetraplegia. J Spinal Cord Med. 2012;35(3):182–186.

 PubMed Web of Science ®Google Scholar

Dolbow DR, Credeur DP. Effects of resistance-guided high intensity interval functional electrical stimulation cycling on an individual with paraplegia: a case report. J Spinal Cord Med. 2018;41(2):248–252.

 PubMed Web of Science ®Google Scholar

Hjeltnes N, Aksnes AK, Birkeland KI, et al. Improved body composition after 8 wk of electrically stimulated leg cycling in tetraplegic patients. Am J Physiol Regulat Integr Comp Physiol. 1997;273(3):42–43.

 Web of Science ®Google Scholar

Gorgey AS, Harnish CR, Daniels JA, et al. A report of anticipated benefits of functional electrical stimulation after spinal cord injury. J Spinal Cord Med. 2012;35(2):107–112.

 PubMed Web of Science ®Google Scholar

de Abreu DCC, Cliquet A, Rondina JM, et al. Muscle hypertrophy in quadriplegics with combined electrical stimulation and body weight support training. Int J Rehabil Res. 2008;31(2):171–175.

 PubMed Web of Science ®Google Scholar

Adams MM, Ditor DS, Tarnopolsky MA, et al. The effect of body weight-supported treadmill training on muscle morphology in an individual with chronic, motor-complete spinal cord injury: a case study. J Spinal Cord Med. 2006;29(2):167–171.

 PubMed Web of Science ®Google Scholar

Beck L, Veith D, Linde M, et al. Impact of long-term epidural electrical stimulation enabled task-specific training on secondary conditions of chronic paraplegia in two humans. J Spinal Cord Med. 2020;1:1–6.

 Google Scholar

Terson de Paleville DGL, Harkema SJ, Angeli CA. Epidural stimulation with locomotor training improves body composition in individuals with cervical or upper thoracic motor complete spinal cord injury: a series of case studies. J Spinal Cord Med. 2019;42(1):32–38.

 PubMed Web of Science ®Google Scholar

Karelis AD, Carvalho LP, Castillo MJE, et al. Effect on body composition and bone mineral density of walking with a robotic exoskeleton in adults with chronic spinal cord injury. J Rehabil Med. 2017;49(1):84–87.

 PubMed Web of Science ®Google Scholar

Forrest GF, Sisto SA, Barbeau H, et al. Neuromotor and musculoskeletal responses to locomotor training for an individual with chronic motor complete AIS-B spinal cord injury. J Spinal Cord Med. 2008;31(5):509–521.

 PubMed Web of Science ®Google Scholar

Masani K, Alizadeh-Meghrazi M, Sayenko DG, et al. Muscle activity, cross-sectional area, and density following passive standing and whole body vibration: a case series. J Spinal Cord Med. 2014;37(5):575–581.

 PubMed Web of Science ®Google Scholar

Asselin P, Cirnigliaro CM, Kornfeld S, et al. Effect of exoskeletal-assisted walking on soft tissue body composition in persons with spinal cord injury. Arch Phys Med Rehabil. 2021;102(2):196–202.

 PubMed Web of Science ®Google Scholar

Gorgey AS, Moore PD, Wade RC, et al. Disruption in bone marrow fat may attenuate testosterone action on muscle size after spinal cord injury: a case report. Eur J Phys Rehabil Med. 2017;53(4):625–629.

 PubMed Web of Science ®Google Scholar

Gorgey AS, Lester RM, Ghatas MP, et al. Dietary manipulation and testosterone replacement therapy may explain changes in body composition after spinal cord injury: a retrospective case report. World J Clin Cases. 2019;7(17):2427–2437.

 PubMed Web of Science ®Google Scholar

Halstead LS, Groah SL, Libin A, et al. The effects of an anabolic agent on body composition and pulmonary function in tetraplegia: a pilot study. Spinal Cord. 2010;48(1):55–59.

 PubMed Web of Science ®Google Scholar

Holman ME, Gorgey AS. Testosterone and resistance training improve muscle quality in spinal cord injury. Med Sci Sports Exerc. 2019;51(8):1591–1598.

 PubMed Web of Science ®Google Scholar

Gorgey AS, Graham ZA, Chen Q, et al. Sixteen weeks of testosterone with or without evoked resistance training on protein expression, fiber hypertrophy and mitochondrial health after spinal cord injury. J Appl Physiol. 2020;128(6):1487–1496.

 PubMed Web of Science ®Google Scholar

Menéndez H, Ferrero C, Martín-Hernández J, et al. Chronic effects of simultaneous electromyostimulation and vibration on leg blood flow in spinal cord injury. Spinal Cord. 2016;54(12):1169–1175.

 PubMed Web of Science ®Google Scholar

Gorgey AS, Abilmona SM, Sima A, et al. A secondary analysis of testosterone and electrically evoked resistance training versus testosterone only (TEREX-SCI) on untrained muscles after spinal cord injury: a pilot randomized clinical trial. Spinal Cord. 2020;58(3):298–308.

 PubMed Web of Science ®Google Scholar

Gorgey AS, Khalil RE, Gill R, et al. Low-dose testosterone and evoked resistance exercise after spinal cord injury on cardio-metabolic risk factors: an open-label randomized clinical trial. J Neurotrauma. 2019;36(18):2631–2645.

 PubMed Web of Science ®Google Scholar

Yarar-Fisher C, Polston KFL, Eraslan M, et al. Paralytic and nonparalytic muscle adaptations to exercise training versus high-protein diet in individuals with long-standing spinal cord injury. J Appl Physiol. 2018;125(1):64–72.

 PubMed Web of Science ®Google Scholar

Kern H, Rossini K, Carraro U, et al. Muscle biopsies show that FES of denervated muscles reverses human muscle degeneration from permanent spinal motoneuron lesion. J Rehabil Res Dev. 2005;42(3 Suppl 1):43–53.

 PubMedGoogle Scholar

Crameri RM, Cooper P, Sinclair PJ, et al. Effect of load during electrical stimulation training in spinal cord injury. Muscle Nerve. 2004;29(1):104–111.

 PubMed Web of Science ®Google Scholar

Deley G, Denuziller J, Casillas JM, et al. One year of training with FES has impressive beneficial effects in a 36-year-old woman with spinal cord injury. J Spinal Cord Med. 2017;40(1):107–112.

 PubMed Web of Science ®Google Scholar

Murphy RJL, Hartkopp A, Gardiner PF, et al. Salbutamol effect in spinal cord injured individuals undergoing functional electrical stimulation training. Arch Phys Med Rehabil. 1999;80(10):1264–1267.

 PubMed Web of Science ®Google Scholar

Scremin AME, Kurta L, Gentili A, et al. Increasing muscle mass in spinal cord injured persons with a functional electrical stimulation exercise program. Arch Phys Med Rehabil. 1999;80(12):1531–1536.

 PubMed Web of Science ®Google Scholar

Frotzler A, Coupaud S, Perret C, et al. High-volume FES-cycling partially reverses bone loss in people with chronic spinal cord injury. Bone. 2008;43(1):169–176.

 PubMed Web of Science ®Google Scholar