Muscle RNA responses to combined training plus polyphenols in adults aged 55–70
In 38 adults aged 55–70, 12 weeks of supervised resistance plus high-intensity interval training produced mostly small muscle RNA changes; polyphenol supplements did not meaningfully alter the response. [1]
Automatic summary · not editorially reviewed
The key findings
Thirty-eight adults aged 55–70 years (17 polyphenol, 21 placebo) with paired muscle RNA data took part in a randomized, double-blind trial of 30 days of supplementation followed by 12 weeks of supervised resistance plus high-intensity interval training with continued supplementation. [1]
The group-by-time comparison found 14 significant transcripts, eight also passing the effect-size criterion, with low or sparse expression and high inter-individual variability and no coherent supplementation-related response. [1]
In the pooled before–after analysis, 60 transcripts were significant and seven also passed the effect-size criterion; most significant transcripts had small estimated effects, and enrichment analyses found no robust pathway-level adaptations. [1]
The source at a glance
- Study type / format
- Randomized, double-blind trial (abstract)
- Population / context
- 38 middle-aged and older adults aged 55–70 years (17 polyphenol, 21 placebo) with paired skeletal muscle RNA-sequencing data
- Summary based on
- Study abstract
- Original publication
- October 1, 2026
Randomized trial in adults aged 55–70
The trial enrolled 38 middle-aged and older adults aged 55–70 years, 17 taking polyphenols and 21 taking placebo, all with paired muscle RNA data. It was randomized and double-blind. Participants took supplements for 30 days, then completed a supervised 12-week programme of resistance training plus high-intensity interval training while continuing supplements. Muscle samples from the vastus lateralis, a thigh muscle, were taken before and after training. Analyses were adjusted for age, sex and muscle fibre type composition.
Supporting source [1]
Few transcript changes, no clear polyphenol effect
Before training, the polyphenol and placebo groups differed in only three transcripts meeting the significance threshold, and only HMOX1 also passed the effect-size criterion. The comparison of change over time between groups found 14 significant transcripts, eight also passing the effect-size criterion; these signals showed low or sparse expression and high variability between individuals, without a coherent pattern linked to supplementation. In the pooled before–after analysis, 60 transcripts were significant, seven also passing the effect-size criterion, including higher CLLU1, PRND and LOX and lower MYH1. Most significant transcripts had small estimated effects.
Supporting source [1]
No robust pathway-level signal in this abstract
The authors conclude that 12 weeks of combined training produced a mainly low-magnitude transcriptional response in muscle. Some transcript changes were consistent with processes of extracellular matrix remodelling and contractile regulation, but functional enrichment analyses found no robust pathway-level adaptations, which limits conclusions about coordinated biological pathways. The authors state that polyphenol supplementation did not meaningfully influence the transcriptional response to training. This summary is based on the abstract only; the full text was not reviewed.
Supporting source [1]
How to interpret this
Abstract only; the full text was not reviewed. The abstract reports no follow-up beyond the 12-week programme and no data on muscle function or clinical outcomes. Transcript-level findings with small effects and no robust pathway enrichment cannot establish coordinated biological adaptations or causal effects of training or polyphenols.
Based on the study abstract; the full paper, tables and supplementary data were not reviewed.
Source & supporting passages
Guadalupe-Grau A, Gudra D, Lismane D, Raudeniece J, Akuratere G, Viksne K, Gailite L, Vilne B, Pivovarova-Ramich O, Flensted-Jensen M, Dela F, Reihmane D. · europepmc.org · October 1, 2026