Exercise and food restriction in rats.
Level 5 - mechanism / opinion, no new human data
Animal research and narrative review
PubMed 1542046 · doi:10.1093/jn/122.suppl_3.774
What was done
Reviewed findings from studies evaluating the effects of voluntary wheel running, food restriction, and their combination on the average survival, maximal lifespan, and mortality trajectories of male specific-pathogen-free Long-Evans rats.
What was found
Voluntary wheel running extended average survival compared with sedentary ad libitum-fed controls but did not increase maximal lifespan. Sedentary food-restricted rats weight-matched to runners lived longer than runners and achieved maximal lifespan extension. Combining wheel running with food restriction (~30% below ad libitum) increased mortality over the first ~50% of the mortality curve up to ~900 days of age. Runners surviving past ~900 days had survival similar to sedentary food-restricted controls and retained the increase in maximal lifespan. Exact sample sizes and numerical lifespan values were not provided in the abstract.
Why it matters
This work demonstrates in a rodent model that physical exercise and caloric restriction modulate longevity through distinct patterns, and that combining high activity with caloric restriction may increase early-life mortality risk.
Limits
Findings are limited to male Long-Evans rats under laboratory conditions and cannot be directly translated to humans or female animals. The abstract provides narrative generalizations without sample sizes, exact statistical comparisons, effect sizes, variance estimates, or cause-of-death analyses.
Cited by
- supports In animals, exercise alone without calorie restriction or intermittent fasting produces only a minimal lifespan extension (around 5%).