title: The effect of strength training volume on satellite cells, myogenic regulatory factors, and growth factors.
abstract: The aim of this work was to study the effect of training volume on activation of satellite cells. Healthy untrained men were randomly assigned into two groups. The 3L-1UB group (n = 10) performed three-set leg exercises and single-set upper body exercises, and the 1L-3UB group (n = 11) performed single-set leg exercises and three-set upper body exercises. Both groups performed three sessions (80-90 min) per week for 11 weeks. Biopsies were taken from m. vastus lateralis and m. trapezius. The number of satellite cells, satellite cells positive for myogenin and MyoD, and the number of myonuclei were counted. Homogenized muscle was analyzed for myogenin and MyoD, and extracted ribonucleic acid (RNA) was monitored for selected growth factor transcripts. Knee extensor strength increased more in the 3L-1UB group than in the 1L-3UB group (48 ± 4% vs 29 ± 4%), whereas the strength gain in shoulder press was similar in both training groups. The number of satellite cells in m. vastus lateralis increased more in the 3L-1UB group than in the 1L-3UB group. The number of myonuclei increased similarly in both groups. The messenger RNA expression of growth factors peaked after 2 weeks of training. In conclusion, increasing training volume enhanced satellite cell numbers in the leg muscle, but not in the upper body muscle.
authors.affiliation: Faculty of Education, Østfold University College, Halden, Norway; Norwegian School of Sport Sciences, Oslo, Norway.
authors.forename: K E
authors.initials: KE
authors.lastname: Hanssen
authors.forename: N H
authors.initials: NH
authors.lastname: Kvamme
authors.forename: T S
authors.initials: TS
authors.lastname: Nilsen
authors.forename: B
authors.initials: B
authors.lastname: Rønnestad
authors.forename: I K
authors.initials: IK
authors.lastname: Ambjørnsen
authors.forename: F
authors.initials: F
authors.lastname: Norheim
authors.forename: F
authors.initials: F
authors.lastname: Kadi
authors.forename: J
authors.initials: J
authors.lastname: Hallèn
authors.forename: C A
authors.initials: CA
authors.lastname: Drevon
authors.forename: T
authors.initials: T
authors.lastname: Raastad
mesh_terms: D000328:Adult; D064131:Back Muscles / Q000033:anatomy & histology* / Q000378:metabolism; D015153:Blotting, Western; D015444:Exercise / Q000502:physiology; D016222:Fibroblast Growth Factor 2 / Q000235:genetics; D017228:Hepatocyte Growth Factor / Q000235:genetics; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000235:genetics; D008297:Male; D018485:Muscle Fibers, Skeletal / Q000166:cytology*; D053580:Muscle Strength; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000378:metabolism; D017570:MyoD Protein / Q000378:metabolism; D018006:Myogenic Regulatory Factors / Q000378:metabolism; D018008:Myogenin / Q000378:metabolism; D055435:Myostatin / Q000235:genetics; D052097:Quadriceps Muscle / Q000033:anatomy & histology* / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis*; D055070:Resistance Training / Q000379:methods*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D032496:Satellite Cells, Skeletal Muscle / Q000166:cytology*; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics
chemical_list: C066855:HGF protein, human; C583557:IGF1 protein, human; C525911:MSTN protein, human; C503799:MYOG protein, human; D017570:MyoD Protein; C057363:MyoD1 myogenic differentiation protein; D018006:Myogenic Regulatory Factors; D018008:Myogenin; D055435:Myostatin; D012333:RNA, Messenger; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D016222:Fibroblast Growth Factor 2; D017228:Hepatocyte Growth Factor; D007334:Insulin-Like Growth Factor I