Paralytic and nonparalytic muscle adaptations to exercise training versus high-protein diet in individuals with long-standing spinal cord injury

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Yarar-Fisher C., Polston K. F. L., Eraslan M., Henley K. Y., Kinikli G. İ., Bickel C. S., ...Daha Fazla

JOURNAL OF APPLIED PHYSIOLOGY, cilt.125, ss.64-72, 2018 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 125
  • Basım Tarihi: 2018
  • Doi Numarası: 10.1152/japplphysiol.01029.2017
  • Dergi Adı: JOURNAL OF APPLIED PHYSIOLOGY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.64-72
  • Anahtar Kelimeler: diet, exercise, fiber type, skeletal muscle, spinal cord injury, HUMAN SKELETAL-MUSCLE, ELECTRICAL-STIMULATION, RESISTANCE EXERCISE, OLDER-ADULTS, MYOFIBER HYPERTROPHY, PARAPLEGIC SUBJECTS, GLUCOSE-TOLERANCE, BED REST, YOUNG, MEN
  • Hacettepe Üniversitesi Adresli: Evet

Özet

This study compares the effects of an 8-wk isocaloric high-protein (HP) diet versus a combination exercise (Comb-Ex) regimen on paralytic vastus lateralis (VL) and nonparalytic deltoid muscle in individuals with long-standing spinal cord injury (SCI). Fiber-type distribution, cross-sectional area (CSA). levels of translation initiation signaling proteins (Erk-1/2, Akt, p70S6K1, 4EBP1, RPS6, and FAK), and lean thigh mass were analyzed at baseline and after the 8-wk interventions. A total of 11 participants (C5-T12 levels, 21.8 +/- 6.3 yr postinjury; 6 Comb-Ex and 5 HP diet) completed the study. Comb-Ex training occurred 3 days/wk and consisted of upper body resistance training (RT) in addition to neuromuscular electrical stimulation (NMES)-induced-RT for paralytic VL muscle. Strength training was combined with high-intensity arm-cranking exercises (1-min intervals at 85-90%, (V) over dotO(2peak)) for improving cardiovascular endurance. For the HP diet intervention, protein and fat each comprised 30%. and carbohydrate comprised 40% of total energy. Clinical tests and muscle biopsies were performed 24 h before and after the last exercise or diet session. The Comb-Ex intervention increased Type IIa myofiber distribution and CSA in VL muscle and Type I and IIa myofiber CSA in deltoid muscle. In addition, Comb-Ex increased lean thigh mass, (V) over dotO(2peak), and upper body strength (P < 0.05). These results suggest that exercise training is required to promote favorable changes in paralytic and nonparalytic muscles in individuals with long-standing SCI, and adequate dietary protein consumption alone may not be sufficient to ameliorate debilitating effects of paralysis.

This study compares the effects of an 8-wk isocaloric high-protein (HP) diet versus a combination exercise (Comb-Ex) regimen on paralytic vastus lateralis (VL) and nonparalytic deltoid muscle in individuals with long-standing spinal cord injury (SCI). Fiber-type distribution, cross-sectional area (CSA), levels of translation initiation signaling proteins (Erk-1/2, Akt, p70S6K1, 4EBP1, RPS6, and FAK), and lean thigh mass were analyzed at baseline and after the 8-wk interventions. A total of 11 participants (C5-T12 levels, 21.8 ± 6.3 yr postinjury; 6 Comb-Ex and 5 HP diet) completed the study. Comb-Ex training occurred 3 days/wk and consisted of upper body resistance training (RT) in addition to neuromuscular electrical stimulation (NMES)-induced-RT for paralytic VL muscle. Strength training was combined with high-intensity arm-cranking exercises (1-min intervals at 85-90%, V̇o2peak) for improving cardiovascular endurance. For the HP diet intervention, protein and fat each comprised 30%, and carbohydrate comprised 40% of total energy. Clinical tests and muscle biopsies were performed 24 h before and after the last exercise or diet session. The Comb-Ex intervention increased Type IIa myofiber distribution and CSA in VL muscle and Type I and IIa myofiber CSA in deltoid muscle. In addition, Comb-Ex increased lean thigh mass, V̇o2peak, and upper body strength ( P < 0.05). These results suggest that exercise training is required to promote favorable changes in paralytic and nonparalytic muscles in individuals with long-standing SCI, and adequate dietary protein consumption alone may not be sufficient to ameliorate debilitating effects of paralysis. NEW & NOTEWORTHY This study is the first to directly compare the effects of an isocaloric high-protein diet and combination exercise training on clinical and molecular changes in paralytic and nonparalytic muscles of individuals with long-standing spinal cord injury. Our results demonstrated that muscle growth and fiber-type alterations can best be achieved when the paralyzed muscle is sufficiently loaded via neuromuscular electrical stimulation-induced resistance training.