How Swimming and Running Affect the Heart Differently
New research from Brazil’s Federal University of São Paulo (UNIFESP) reveals that swimming and running impact the heart at a molecular level in distinct ways, even though both activities improve cardiovascular endurance. Swimming triggers deeper structural changes in the heart and activates specific molecular pathways that remain dormant during running. The study, funded by the FAPESP foundation, was led by Professor André Jorge Serra.
Study Methodology
Using a mouse model, researchers divided the animals into three groups: a sedentary control group, a running group, and a swimming group. The training program lasted 8 weeks, with 60-minute sessions conducted five times per week. Exercise intensity was tracked using VO₂ max, which increased by over 5% in both active groups. However, only the swimming group experienced a significant increase in total heart mass and left ventricular mass. The running group showed no statistically meaningful structural changes in the heart.
Professor Serra noted: 'Swimming and running are both excellent ways to improve cardiorespiratory fitness and protect the heart muscle, but we wanted to determine if one might be even more beneficial than the other.'
At the molecular level, swimming induces stronger alterations in microRNAs associated with cardiac adaptation. The research also analyzed gene expression and protein signaling pathways linked to physiological cardiac hypertrophy. Professor Serra emphasized the significance of the work, stating, 'While several studies have already examined microRNA expression regulated by aerobic exercise in general, little was known about these expression patterns when directly comparing swimming and running within a single experimental model.'
The findings were published in the journal Scientific Reports and could carry important implications for understanding how different types of physical activity influence the cardiovascular system.
These results open new avenues for exploring exercise and its effects on heart health. Understanding the molecular mechanisms behind cardiac adaptation to various forms of exertion may aid in designing more effective training and rehabilitation programs for patients with cardiovascular disease. Future studies could focus on identifying the optimal types of physical activity for improving heart health across different age groups and individual needs.
As research continues to unveil the intricate ways exercise impacts heart health, it's essential to consider how current protein and activity recommendations might need reevaluation. Understanding the nuanced effects of different types of exercise can help individuals make more informed choices for their cardiovascular fitness.