oru.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Impact of testosterone therapy and strength training on muscle fibercross-sectional area, myonuclei and satellite cells in older men
Örebro University, School of Health Sciences.
2018 (English)Student thesis
Abstract [en]

Background: Sarcopenia is associated with age-related deterioration of muscle mass andstrength. Testosterone therapy has been offered as a counter-acting measure to deterioration ofmuscle mass and strength. Strength training is known to improve muscle mass and strength, thuscounteracting age-related deterioration of muscle mass and strength. Furthermore, testosteronetherapy has also been shown to have positive effects on muscle mass and strength. However, theeffects of testosterone therapy and strength training in previously trained older adults are lessknown and the combined effects of strength training plus testosterone are less known.

Aim: The aim of this study is two-fold 1) to evaluate the efficacy of 24 weeks of strengthtraining or testosterone therapy on changes in muscle fiber CSA, satellite cells and myonuclei inolder men with low bioavailable testosterone levels and 2) to evaluate in a group of alreadystrength trained subjects, whether 12 weeks with strength training alone or strength training plustestosterone can affect the same muscular parameters.

Method: Older men, 60-78 years old, were randomized into 1) placebo, 2) testosterone or 3)strength training group for 24 weeks. Strength training group was further divided at week 12 intostrength training plus placebo or strength training plus testosterone for the remaining 12 weeks.Subjects followed a progressive strength training program at 6 to 10 RM. Testosterone treatmentconsisted of 50 mg/day of testosterone. Muscle strength (10-RM) and lean body mass (LBM)were measured with standardized procedures. Using muscle biopsies from vastus lateralis musclefiber cross-sectional area (CSA), number of satellite cells and myonuclei were measured usingimmunohistochemistry.

Results: All parameters remained unchanged for the placebo group. Testosterone groupsignificantly increased LBM, type IIA muscle fiber CSA and satellite cells in type IIA musclefibers, but not muscle strength or myonuclear number. Strength training improved musclestrength, muscle fiber CSA (type I and IIA), satellite cell number (type IIA), myonuclear number(type I and IIA) and LBM at week 24. In already strength trained subjects, there were nosignificant differences in any muscular parameters between strength training alone and strengthtraining plus testosterone.

Conclusion: The findings from this study support a greater myogenic effect of resistance training compared totestosterone treatment in older adults and does not support the notion that strength training plustestosterone would be superior to strength training alone.

Keywords: sarcopenia, testosterone, strength training, muscle fiber, myonuclei, satellite cells

Place, publisher, year, edition, pages
2018.
Identifiers
URN: urn:nbn:se:oru:diva-74814OAI: oai:DiVA.org:oru-74814DiVA, id: diva2:1331264
Examiners
Available from: 2019-06-26 Created: 2019-06-26

Open Access in DiVA

No full text in DiVA

By organisation
School of Health Sciences

Search outside of DiVA

GoogleGoogle Scholar

urn-nbn

Altmetric score

urn-nbn
Total: 14 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf