Neuromuscular electrical stimulation resistance training enhances oxygen uptake and ventilatory efficiency independent of mitochondrial complexes after spinal cord injury: a randomized clinical trial.
J Appl Physiol (1985)
; 131(1): 265-276, 2021 07 01.
Article
en En
| MEDLINE
| ID: mdl-33982590
ABSTRACT
The purpose of the study was to determine whether neuromuscular electrical stimulation resistance training (NMES-RT)-evoked muscle hypertrophy is accompanied by increased VÌo2 peak, ventilatory efficiency, and mitochondrial respiration in individuals with chronic spinal cord injury (SCI). Thirty-three men and women with chronic, predominantly traumatic SCI were randomized to either NMES-RT (n = 20) or passive movement training (PMT; n = 13). Functional electrical stimulation-lower extremity cycling (FES-LEC) was used to test the leg VÌo2 peak, VÌE/VÌco2 ratio, and substrate utilization pre- and postintervention. Magnetic resonance imaging was used to measure muscle cross-sectional area (CSA). Finally, muscle biopsy was performed to measure mitochondrial complexes and respiration. The NMES-RT group showed a significant increase in postintervention VÌo2 peak compared with baseline (ΔVÌo2 = 14%, P < 0.01) with no changes in the PMT group (ΔVÌo2 = 1.6%, P = 0.47). Similarly, thigh (ΔCSAthigh = 19%) and knee extensor (ΔCSAknee = 30.4%, P < 0.01) CSAs increased following NMES-RT but not after PMT. The changes in thigh and knee extensor muscle CSAs were positively related with the change in VÌo2 peak. Neither NMES-RT nor PMT changed mitochondrial complex tissue levels; however, changes in peak VÌo2 were related to complex I. In conclusion, in persons with SCI, NMES-RT-induced skeletal muscle hypertrophy was accompanied by increased peak VÌo2 consumption which may partially be explained by enhanced activity of mitochondrial complex I.NEW & NOTEWORTHY Leg oxygen uptake (VÌo2) and ventilatory efficiency (VÌE/VÌco2 ratio) were measured during functional electrical stimulation cycling testing following 12-16 wk of either electrically evoked resistance training or passive movement training, and the respiration of mitochondrial complexes. Resistance training increased thigh muscle area and leg VÌo2 peak but decreased VÌE/VÌco2 ratio without changes in mitochondrial complex levels. Leg VÌo2 peak was associated with muscle hypertrophy and mitochondrial respiration of complex I following training.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Traumatismos de la Médula Espinal
/
Terapia por Estimulación Eléctrica
/
Entrenamiento de Fuerza
Tipo de estudio:
Clinical_trials
Límite:
Female
/
Humans
/
Male
Idioma:
En
Revista:
J Appl Physiol (1985)
Asunto de la revista:
FISIOLOGIA
Año:
2021
Tipo del documento:
Article