oru.sePublikasjoner
Endre søk
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Skeletal Muscle Mass & Function in Older Women: Health-Enhancing Influences of Combined Resistance Exercise & Diet
Örebro universitet, Institutionen för hälsovetenskaper.
2017 (engelsk)Doktoravhandling, med artikler (Annet vitenskapelig)
Abstract [en]

Ageing is accompanied by a progressive decline in skeletal muscle mass and strength which may lead to impaired ability to perform activities of daily living in older adults. Although the exact cause of the gradual decline in muscle mass is unknown, identifying efficient strategies aiming to prevent age-related loss of muscle mass and strength is important in order to promote healthy ageing. The overall aim of this thesis was to explore the effects of resistance training alone or combined with a healthy diet on skeletal muscle mass and function of healthy recreationally active older women and to determine mechanisms by which elevated systemic inflammation may contribute to the age-related decline of muscle mass in older adults. The combination of resistance training and a healthy diet induced gains in leg lean mass as well as greater gains in dynamic explosive force than resistance training alone in healthy recreationally active older women. The observed gains in leg lean mass were accompanied by increases in the size of type IIA muscle fibres together with down-regulation in gene expression of a pro-inflammatory factor (IL-1β) and upregulation in gene expression of a regulator of cellular growth (mTOR) in skeletal muscle of older women. Additionally, reduced muscle protein synthesis and size of muscle cells may mediate the detrimental effects of elevated circulating markers of inflammation on muscle mass in older adults. In conclusion, the present thesis depicts mechanistic links between elevated systemic marker of inflammation and muscle mass and provides new information on the effects of combined resistance training and healthy diet on muscle mass and strength in a group of healthy recreationally active older women. This knowledge is instrumental for development of strategies aiming to prevent age-related loss of muscle mass and function.

sted, utgiver, år, opplag, sider
Örebro: Örebro University , 2017. , 79 s.
Serie
Örebro Studies in Sport Sciences, ISSN 1654-7535 ; 26
Emneord [en]
Healthy ageing, Chronic inflammation, C-reactive protein, Omega-3 fatty acids, Resistance training, Physical function
HSV kategori
Identifikatorer
URN: urn:nbn:se:oru:diva-61234ISBN: 978-91-7529-218-2 (tryckt)OAI: oai:DiVA.org:oru-61234DiVA: diva2:1146669
Disputas
2017-12-12, Örebro universitet, Hörsal G, Gymnastikhuset, Fakultetsgatan 1, Örebro, 09:00 (svensk)
Opponent
Veileder
Tilgjengelig fra: 2017-10-03 Laget: 2017-10-03 Sist oppdatert: 2017-11-23bibliografisk kontrollert
Delarbeid
1. Influence of combined resistance training and healthy diet on muscle mass in healthy elderly women: a randomized controlled trial
Åpne denne publikasjonen i ny fane eller vindu >>Influence of combined resistance training and healthy diet on muscle mass in healthy elderly women: a randomized controlled trial
Vise andre…
2015 (engelsk)Inngår i: Journal of applied physiology, ISSN 8750-7587, E-ISSN 1522-1601, Vol. 119, nr 8, 918-925 s.Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

The delivery of efficient nonpharmacological treatment to prevent the loss of muscle mass in older adults is a major challenge, and information on the combined effects of training and diet is particularly important. Here we aimed to evaluate the effects of 24 wk of resistance training combined with a healthy dietary approach (n-6/n-3 ratio < 2) in a population of healthy and physically active older women (65-70 years). The three-armed randomized controlled trial included a resistance training + healthy diet group (RT-HD), a resistance training group (RT), and controls (CON). All subjects included in the study were physically active and had low levels of serum inflammatory markers. In accordance with the dietary goals, the n-6/n-3 ratio dietary intake significantly decreased only in RT-HD by 42%. An increase in 1 repetition maximum in leg extension occurred in RT (+20.4%) and RT-HD (+20.8%), but not in CON. Interestingly, leg lean mass significantly increased only in RT-HD (+1.8%). While there were no changes in serum C-reactive protein and IL-6 levels, a significant decrease in serum level of the pro-inflammatory precursor arachidonic acid (-5.3 +/- 9.4%) together with an increase in serum n-3 docosahexaenoic acid (+8.3%) occurred only in RT-HD. Altogether, this study demonstrates that the effects of resistance training on muscle mass in healthy older adults can be optimized by the adoption of a healthy diet.

sted, utgiver, år, opplag, sider
American Physiological Society, 2015
Emneord
aging, C-reactive protein, exercise, fatty acids, inflammation, skeletal muscle
HSV kategori
Forskningsprogram
Fysiologi
Identifikatorer
urn:nbn:se:oru:diva-46442 (URN)10.1152/japplphysiol.00066.2015 (DOI)000362959800009 ()26338453 (PubMedID)2-s2.0-84946046698 (Scopus ID)
Merknad

Funding Agency:

Swedish National Center for Research in Sports P2012/0102 P2014-0117

Tilgjengelig fra: 2015-11-10 Laget: 2015-11-10 Sist oppdatert: 2018-01-10bibliografisk kontrollert
2. Lower limb explosive strength capacity in elderly women: effects of resistance training and healthy diet
Åpne denne publikasjonen i ny fane eller vindu >>Lower limb explosive strength capacity in elderly women: effects of resistance training and healthy diet
2017 (engelsk)Inngår i: Journal of applied physiology, ISSN 8750-7587, E-ISSN 1522-1601, Vol. 123, nr 1, 190-196 s.Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

The effects of 24 wk of resistance training combined with a healthy diet on lower limb explosive strength capacity were investigated in a population of healthy elderly women. Participants (n = 63; 67.5 ± 0.4 yr) were randomized into three groups; resistance training (RT), resistance training and healthy diet (RT-HD), and control (CON). Progressive resistance training was performed at a load of 75-85% one-repetition maximum. A major adjustment in the healthy dietary approach was an n-6/n-3 polyunsaturated fatty acid (PUFA) ratio below 2. Lower limb maximal strength, explosive force capacity during dynamic and isometric movements, whole body lean mass, and physical function were assessed. Whole body lean mass significantly increased by 1.5 ± 0.5% in RT-HD only. Isometric strength performance during knee extension as well as the performance in the five sit-to-stand and single-leg-stance tests increased similarly in RT and RT-HD. Improvements in dynamic peak power and time to reach peak power (i.e shorter time) during knee extension occurred in both RT (+15.7 ± 2.6 and -11.0 ± 3.8%, respectively) and RT-HD (+24.6 ± 2.6 and -20.3 ± 2.7%, respectively); however, changes were significantly larger in RT-HD. Similarly, changes in peak force and rate of force development during squat jump were higher in RT-HD (+58.5 ± 8.4 and +185.4 ± 32.9%, respectively) compared with RT (+35.7 ± 6.9 and +105.4 ± 22.4%, respectively). In conclusion, a healthy diet rich in n-3 PUFA can optimize the effects of resistance training on dynamic explosive strength capacity during isolated lower limb movements and multijoint exercises in healthy elderly women.

NEW & NOTEWORTHY Age-related decline in lower limb explosive strength leads to impaired ability to perform daily living tasks. The present randomized controlled trial demonstrates that a healthy diet rich in n-3 polyunsaturated fatty acid (n-3 PUFA) enhances resistance training-induced gains in dynamic explosive strength capacity during isolated lower limb movements and multijoint exercises in healthy elderly women. This supports the use of strategies combining resistance training and dietary changes to mitigate the decline in explosive strength capacity in older adults.

sted, utgiver, år, opplag, sider
American Physiological Society, 2017
Emneord
aging, muscle mass, omega-3 fatty acids, physical function, rate of force development
HSV kategori
Identifikatorer
urn:nbn:se:oru:diva-60897 (URN)10.1152/japplphysiol.00924.2016 (DOI)28473614 (PubMedID)
Tilgjengelig fra: 2017-09-19 Laget: 2017-09-19 Sist oppdatert: 2017-11-23bibliografisk kontrollert
3. Mechanisms mediating skeletal muscle hypertrophy in older women following resistanceexercise combined to healthy diet
Åpne denne publikasjonen i ny fane eller vindu >>Mechanisms mediating skeletal muscle hypertrophy in older women following resistanceexercise combined to healthy diet
Vise andre…
(engelsk)Manuskript (preprint) (Annet vitenskapelig)
HSV kategori
Identifikatorer
urn:nbn:se:oru:diva-62773 (URN)
Tilgjengelig fra: 2017-11-23 Laget: 2017-11-23 Sist oppdatert: 2017-11-23bibliografisk kontrollert
4. Mechanistic Links Underlying the Impact of C-Reactive Protein on Muscle Mass in Elderly
Åpne denne publikasjonen i ny fane eller vindu >>Mechanistic Links Underlying the Impact of C-Reactive Protein on Muscle Mass in Elderly
Vise andre…
2017 (engelsk)Inngår i: Cellular Physiology and Biochemistry, ISSN 1015-8987, E-ISSN 1421-9778, Vol. 44, nr 1, 267-278 s.Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

BACKGROUND/AIMS: Mechanisms underlying the relationship between systemic inflammation and age-related decline in muscle mass are poorly defined. The purpose of this work was to investigate the relationship between the systemic inflammatory marker CRP and muscle mass in elderly and to identify mechanisms by which CRP mediates its effects on skeletal muscle, in-vitro.

METHODS: Muscle mass and serum CRP level were determined in a cohort of 118 older women (67±1.7 years). Human muscle cells were differentiated into myotubes and were exposed to CRP. The size of myotubes was determined after immunofluorescent staining using troponin. Muscle protein synthesis was assessed using stable isotope tracers and key signalling pathways controlling protein synthesis were determined using western-blotting.

RESULTS: We observed an inverse relationship between circulating CRP level and muscle mass (β= -0.646 (95% CI: -0.888, -0.405) p<0.05) and demonstrated a reduction (p < 0.05) in the size of human myotubes exposed to CRP for 72 h. We next showed that this morphological change was accompanied by a CRP-mediated reduction (p < 0.05) in muscle protein fractional synthetic rate of human myotubes exposed to CRP for 24 h. We also identified a CRP-mediated increased phosphorylation (p<0.05) of regulators of cellular energy stress including AMPK and downstream targets, raptor and ACC-β, together with decreased phosphorylation of Akt and rpS6, which are important factors controlling protein synthesis.

CONCLUSION: This work established for the first time mechanistic links by which chronic elevation of CRP can contribute to age-related decline in muscle function.

sted, utgiver, år, opplag, sider
Karger, 2017
Emneord
AMPK, Ageing, Akt/mTOR, CRP, Chronic Inflammation, Myoblast, Old women, Protein Synthesis, Skeletal Muscle Cell
HSV kategori
Identifikatorer
urn:nbn:se:oru:diva-62772 (URN)10.1159/000484679 (DOI)29130969 (PubMedID)2-s2.0-85033489852 (Scopus ID)
Tilgjengelig fra: 2017-11-23 Laget: 2017-11-23 Sist oppdatert: 2017-12-07bibliografisk kontrollert

Open Access i DiVA

Cover(75 kB)1 nedlastinger
Filinformasjon
Fil COVER01.pdfFilstørrelse 75 kBChecksum SHA-512
cf60a11113ca2f9e56d929742383451f0a3e825c88757e6614b3f7fab08b6201c43e714e69e88fcd6592d0901c83bf5b403c720c81990c42c8bb3e2eb8b6afdd
Type coverMimetype application/pdf
Spikblad(184 kB)5 nedlastinger
Filinformasjon
Fil SPIKBLAD01.pdfFilstørrelse 184 kBChecksum SHA-512
a46df612a3293d06bad05a7be762dcbecd328564b3527de7894d40233c7bce6db8fe93c49d0e87a1eb48a35de9852d0213589b919f640aa2c5b4abfcc363d26c
Type spikbladMimetype application/pdf
Skeletal Muscle Mass & Function in Older Women: Health-Enhancing Influences of Combined Resistance Exercise & Diet(1234 kB)14 nedlastinger
Filinformasjon
Fil FULLTEXT01.pdfFilstørrelse 1234 kBChecksum SHA-512
8e8f01b8ca79af6d6ff126b14c1d8a78816e514e28528fd2a56b9ca9e7007b03078e97b3529997b4f71bd5ca5966451b5954ed6812c14839795a4c8266af0cde
Type fulltextMimetype application/pdf

Personposter BETA

Strandberg, Emelie

Søk i DiVA

Av forfatter/redaktør
Strandberg, Emelie
Av organisasjonen

Søk utenfor DiVA

GoogleGoogle Scholar
Totalt: 14 nedlastinger
Antall nedlastinger er summen av alle nedlastinger av alle fulltekster. Det kan for eksempel være tidligere versjoner som er ikke lenger tilgjengelige

isbn
urn-nbn

Altmetric

isbn
urn-nbn
Totalt: 413 treff
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf