Evidence map›Paper›PMID 22984247›Full record

ArticleJournal of applied physiology (Bethesda, Md. : 1985)2012

Aerobic exercise training induces skeletal muscle hypertrophy and age-dependent adaptations in myofiber function in young and older men.

Matthew P Harber, Adam R Konopka, Miranda K Undem, James M Hinkley, Kiril Minchev, Leonard A Kaminsky, Todd A Trappe, Scott Trappe

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PubMed Full text at PMC Publisher
In one paragraph

Article in Journal of applied physiology (Bethesda, Md. : 1985), 2012. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 113 papers, 6 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
113citing papers in PubMed, 6 pooled it
12.1field-weighted citation impact, top 1% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

113 citing papers in PubMed, 6 syntheses or guidelines pooled it, 213 citations in OpenAlex.

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  15. Exercise, Exerkines, and Sarcopenia.Diabetes & metabolism journal · 2026
    Review
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53 more citing papers are in PubMed but not listed here.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

8 authors at 1 institution in 1 country.

Matthew P HarberHuman Performance Laboratory, Ball State University, Muncie, Indiana 47306, USA. mharber@bsu.edu
Adam R Konopka
Miranda K Undem
James M Hinkley
Kiril Minchev
Leonard A Kaminsky
Todd A Trappe
Scott Trappe
Ball State University · US

Funding

Myocellular Contractile Function with Exercise Training in Older AdultsR15AG032127 · NIA · BALL STATE UNIVERSITY · PI HARBER, MATTHEW · 2009 to 2009
$178k
NIA NIH HHS AG032127NIA NIH HHS R15 AG032127
6 · The paper itself

Abstract

To examine potential age-specific adaptations in skeletal muscle size and myofiber contractile physiology in response to aerobic exercise, seven young (YM; 20 ± 1 yr) and six older men (OM; 74 ± 3 yr) performed 12 wk of cycle ergometer training. Muscle biopsies were obtained from the vastus lateralis to determine size and contractile properties of isolated slow [myosin heavy chain (MHC) I] and fast (MHC IIa) myofibers, MHC composition, and muscle protein concentration. Aerobic capacity was higher (P < 0.05) after training in both YM (16 ± 2%) and OM (13 ± 3%). Quadriceps muscle volume, determined via MRI, was 5 ± 1 and 6 ± 1% greater (P < 0.05) after training for YM and OM, respectively, which was associated with an increase in MHC I myofiber cross-sectional area (CSA), independent of age. MHC I peak power was higher (P < 0.05) after training for both YM and OM, while MHC IIa peak power was increased (P < 0.05) with training in OM only. MHC I and MHC IIa myofiber peak and normalized (peak force/CSA) force were preserved with training in OM, while MHC I peak force/CSA and MHC IIa peak force were lower (P < 0.05) after training in YM. The age-dependent adaptations in myofiber function were not due to changes in protein content, as total muscle protein and myofibrillar protein concentration were unchanged (P > 0.05) with training. Training reduced (P < 0.05) the proportion of MHC IIx isoform, independent of age, whereas no other changes in MHC composition were observed. These data suggest relative improvements in muscle size and aerobic capacity are similar between YM and OM, while adaptations in myofiber contractile function showed a general improvement in OM. Training-related increases in MHC I and MHC IIa peak power reveal that skeletal muscle of OM is responsive to aerobic exercise training and further support the use of aerobic exercise for improving cardiovascular and skeletal muscle health in older individuals.

Indexed as

Adaptation, PhysiologicalAgedAgingExerciseExercise TestHumansHypertrophyMaleMuscle ContractionMuscle Fibers, SkeletalMuscle ProteinsMuscle, SkeletalMyosin Heavy ChainsYoung AdultMuscle ProteinsMyosin Heavy Chains

Identifiers

PMID22984247
PMCPMC3524668
OpenAlexW2031782697

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.