What this means
Researchers studied muscle from younger and older people, some fit and some less fit, before and after one bout of exercise. Half of the age-related muscle differences were missing in trained older adults.
Plain-English summary written by an AI model from the abstract. The original is below.
- Who it was tested in
- Muscle samples from young and older adults with differing physical function
- Kind of research
- A study
The science
- Original title
- Delayed molecular aging, preservation of energy metabolism and enhanced exercise response in exercise-trained human muscle.
- Authors
- Janssens GE, Trętowicz MM, Grevendonk L et al.
- Journal
- Nature aging
- Published
- Jul 3, 2026
- Study type
- Study · in humans
- PMID
- 42399371 ↗
Abstract
Exercise is fundamental to healthy aging, yet how it mitigates age-related molecular changes and how fitness level shapes exercise responses remain unclear. To address these questions, we performed transcriptomics, lipidomics and metabolomics on skeletal muscle of young and older adults with differing physical function, both before and after an acute bout of submaximal exercise. At baseline, older adults exhibited reduced expression of genes associated with cellular respiration and energy metabolism compared to young adults with comparable activity levels. Here we found that 50% of these age-related differences were absent in trained older adults, resulting in profiles resembling those of young adults. Although all participants displayed transcriptional immune and stress responses upon acute exercise, the magnitude of these responses in older adults was positively correlated with their physical fitness. Integrated multiomic analyses further revealed links among mitochondrial respiration, lipid metabolism, stress responses and NAD+ biology. These findings demonstrate that sustained physical training transforms age-related molecular profiles and provide a molecular atlas for study of fitness-dependent aging mechanisms.
Janssens GE, Trętowicz MM, Grevendonk L et al. Delayed molecular aging, preservation of energy metabolism and enhanced exercise response in exercise-trained human muscle. Nature aging. 2026. doi:10.1038/s43587-026-01150-x. PMID: 42399371. https://pubmed.ncbi.nlm.nih.gov/42399371/
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