Structured high- and moderate-intensity exercise over two years reversed heart stiffening in previously sedentary middle-aged adults, improving cardiovascular fitness and potentially reducing future heart failure risk, showing it’s never too late to start exercising.
January 2018 – Circulation
Key takeaways
- Middle-age is the ideal window: Starting a consistent exercise routine in midlife, around ages 45 to 64, taps into a critical period of retained cardiac adaptability. At this stage, the heart can still remodel and regain flexibility, meaning the effects of sedentary ageing aren’t yet fixed. This makes midlife a powerful opportunity to intervene before structural stiffening becomes harder to reverse later in life
- Consistent training remodels the heart: Undertaking two years of structured aerobic training, including high-intensity intervals, led to significant changes in heart structure. Specifically, the heart’s left ventricle became larger and more compliant, allowing it to fill more effectively without increasing internal pressure. This enhanced diastolic function supports better circulation, oxygen delivery, and resilience under stress, cornerstones of long-term cardiovascular health
- Improved fitness lowers heart failure risk: Participants in the exercise group saw an 18% increase in VO₂max, a key indicator of cardiovascular efficiency and predictor of all-cause mortality. This improvement directly correlates with reduced risk of heart failure, especially heart failure with preserved ejection fraction (HFpEF), which is increasingly common with age and currently lacks robust treatment options. Exercise, therefore, offers a powerful preventative tool rooted in measurable biological change
- Almost everyone benefits from training: The programme achieved a 88% adherence rate and showed that virtually every participant improved heart function and fitness, regardless of starting level. Unlike shorter or less intense interventions, this long-term, progressive training regimen produced consistent, universal benefits, dispelling the myth of the “non-responder” and proving that it’s never too late to start seeing meaningful, physiological results from exercise
Read the article at: Howden, Erin J., et al. “Reversing the Cardiac Effects of Sedentary Aging in Middle Age: A Randomized Controlled Trial.” Circulation, vol. 137, no. 15, 2018, pp. 1549–1560. https://doi.org/10.1161/CIRCULATIONAHA.117.030617.
