Muscle Age Clocks: Younger After NR, Partly Older After HIIT
Graded Preliminary — three small studies with 30 to 39 people per group, measured before and after NR or training, with no comparison group on a dummy pill.
- Design
- Non-randomized trial
- Participants
- 106
- Duration
- 5 months
- Funding
- Research Council of Finland, Novo Nordisk Foundation, Sigrid Juselius…
After five months of NR, several epigenetic clocks in muscle read younger, while some ran faster after interval training.
Nicotinamide riboside, or NR, is a building block of vitamin B3. Like hard interval training, it has been proposed as a way to support aging muscles. In muscle, though, the two pointed in opposite directions. After five months of NR, several epigenetic clocks read younger. After four to six weeks of interval training, some clocks ran faster.
Epigenetic clocks estimate biological age from chemical tags on our DNA. The researchers looked at muscle samples from three studies. In one, 30 adult twins aged 30 to 65 took NR, ending at 1,000 milligrams a day. In two others, 39 and 37 people did short, hard intervals three times a week. After NR, three of seven clocks went down, while one went up. After training, the clock that estimates the pace of aging rose in both studies. Another clock fell in the six-week study.
None of the studies compared people with a group on a dummy pill, and the groups were small. The researchers measured clocks, not muscle strength or health. Whether NR actually keeps muscles young cannot be read from this. In muscle cells grown in the lab, NR made no clear difference to the clocks.
Disclaimer: Research summaries are provided for informational purposes only and do not constitute medical advice. Always consult a qualified healthcare professional before making changes to your health routine.