“
TL;DR
This preclinical mouse study found that exercise performed in the early active period led to a 7.8% increase in absolute heart weight, while exercise in the late active period did not cause significant cardiac hypertrophy.
Scientific Reports · 9 authors, 2 centres
This summary was generated by AI from a single paper. It has not been reviewed by a clinician and is not clinical advice. Verify against the source before acting on it.
This preclinical mouse study found that exercise performed in the early active period led to a 7.8% increase in absolute heart weight, while exercise in the late active period did not cause significant cardiac hypertrophy.
The central finding was that exercise in the early active period resulted in a significant 7.8% increase in absolute heart weight, indicating physiologic cardiac hypertrophy, whereas exercise in the late active period did not. There was a trend for increased cardiomyocyte cross-sectional area in the early exercise group. Additionally, the study found that late active period exercise increased expression of the clock gene Per1 in the heart and shifted the phase of daily activity rhythms. A limitation noted is that the final two weeks of exercise involved similar running distances, suggesting the hypertrophy difference may not be solely due to exercise volume. The findings suggest the time of day an exercise stimulus is applied can influence specific cardiovascular adaptations.