New research reported in ScienceDaily points to a lasting payoff from childhood exercise. In a study of guinea fowl, birds that grew up carrying extra weights were later able to carry comparable loads more easily than birds without that early training, suggesting that physical demands during development can change how the body handles exertion in adulthood.
Although the work was done in birds, the researchers see it as a clue to human fitness. If early activity leaves a physiological trace, it could help explain why some adults find exercise less exhausting and why childhood inactivity might have costs that show up years later.
Because only one source was reviewed, there are no conflicting findings to compare. The study's implications for people remain suggestive rather than proven.