FoundMyFitness Podcast Episode #090: How Exercise Prevents & Reverses Heart Aging with Dr. Benjamin Levine, M.D.
Release Date: May 28, 2024
Dr. Rhonda Patrick welcomes Dr. Benjamin Levine, a leading expert in cardiovascular physiology, to discuss groundbreaking research on how exercise can prevent and even reverse aspects of heart aging. Dr. Levine, the founding director of the Institute for Exercise and Environmental Medicine at UT Southwestern in Dallas, shares insights from his extensive studies on cardiovascular adaptation, the impact of sedentary lifestyles, and optimal exercise protocols for maintaining heart health into late adulthood.
1. The Impact of Sedentary Behavior and Bed Rest on Heart Health
Dr. Levine begins by highlighting the detrimental effects of prolonged inactivity on cardiovascular health. Referencing the renowned Dallas Bed Rest study from the 1960s, he explains how three weeks of bed rest led to significant heart atrophy and reduced maximal oxygen uptake, a key marker of cardiovascular fitness.
Dr. Levine [08:22]: “The heart just shrunk in bed rest... probably the single most important thing that happens, at least to the heart.”
He reveals that the negative impacts of short-term bed rest can be worse than 30 years of natural aging in terms of physical work capacity.
Dr. Levine [06:33]: “Not a single person... was in worse shape after 30 years of aging than they were after three weeks of bed rest.”
2. Reversing Heart Aging Through Structured Exercise
Dr. Levine discusses his landmark trial where sedentary individuals underwent a structured, graduated training regimen totaling five to six hours of physical activity per week over two years. The regimen included high-intensity interval training, light aerobic activities, and strength training. The results were remarkable, demonstrating a reversal of up to 20 years of heart aging.
Dr. Levine [27:39]: “We were able to reverse the effects of sedentary aging by sustained training at the right dose, at the right time period in the aging process.”
3. Lifetime Exercise: Consistency is Key
Analyzing retrospective data from the Cooper Clinic, Dr. Levine emphasizes that consistent exercise over a lifetime—specifically four to five days per week—significantly staves off cardiac stiffening and heart shrinkage associated with aging. Casual exercisers (two to three days/week) saw minimal benefits, underscoring the necessity of commitment.
Dr. Levine [08:22]: “A lifetime of endurance training at a level commensurate with being a competitive athlete was sufficient to prevent that aspect of cardiovascular aging.”
4. Exercise as Personal Hygiene for Heart Health
Dr. Levine advocates for treating exercise as a fundamental aspect of personal hygiene, akin to brushing teeth or taking a shower. He outlines an optimal exercise prescription that blends resistance, aerobic, and endurance training to maintain a youthful heart:
- One long session per week (e.g., an hour-long enjoyable activity)
- One high-intensity session per week (e.g., Norwegian 4x4 intervals)
- Two to three moderate-intensity sessions
- One to two strength training days
Dr. Levine [70:08]: “If you do one high intensity session a week and mix it up, that’s what the human body is best at adapting to.”
5. Balancing Exercise Intensity and Duration
Addressing concerns about extreme exercise, Dr. Levine explores the balance between beneficial and potentially risky activities. He discusses studies linking high volumes of endurance exercise to increased coronary artery calcification and a higher risk of atrial fibrillation (afib) in veteran athletes. However, he clarifies that moderate to high-intensity exercise, when balanced with appropriate recovery, continues to confer significant cardiovascular benefits without substantially increasing risks for most individuals.
Dr. Levine [139:16]: “I think, you know, particularly as we've talked about the optimal dose for health and joy and wellness, you know, is up to three hours is what's recommended. Up to three to five hours probably gets you most of the bang for your buck.”
6. Recovery and Overtraining: Listening to Your Body
Emphasizing the importance of recovery, Dr. Levine warns against overtraining, which can lead to diminished performance, increased resting heart rate, and fatigue. He recommends monitoring early morning heart rates as indicators of overtraining and ensuring adequate rest between intense workouts.
Dr. Levine [103:41]: “Recovery is a essential part of training... they were all over trained with marked reduction in performance, increasing resting heart rate, fatigue, every sign of overtraining.”
7. Sex Differences in Cardiovascular Adaptations
Dr. Levine touches on the biological differences between men and women in response to exercise, primarily driven by hormonal influences like testosterone in men. He notes that while both sexes benefit from exercise, men generally achieve higher levels of cardiovascular fitness due to physiological factors.
Dr. Levine [120:34]: “Testosterone builds muscle, reduces fat, builds blood volume, makes the heart bigger, makes the body bigger... That's why we have women's sports, right?”
8. Exercise, Coronary Plaque, and Atrial Fibrillation Risks
Discussing coronary plaque, Dr. Levine explains that while extreme endurance exercise may be associated with increased calcified plaques, overall cardiovascular health remains better in active individuals. He also addresses the nuanced relationship between high-intensity training and atrial fibrillation, concluding that for most recreational exercisers, the benefits outweigh the risks.
Dr. Levine [127:43]: “The bigger the heart is, but is decreased the thicker the heart is. So traditionally, purely strength trained athletes tend to have thicker hearts and what we call concentric hypertrophy as opposed to dilated hearts, which we call eccentric hypertrophy.”
9. VO2 Max and Longevity
Exploring the link between VO2 max (maximal oxygen uptake) and longevity, Dr. Levine explains that higher VO2 max is associated with lower mortality risk. He attributes this to factors such as improved heart size and compliance, better endothelial function, and enhanced autonomic nervous system balance.
Dr. Levine [54:22]: “The heart's adaptive, it gets bigger and more flexible, allowing for greater stroke volume, and that plays a critical role in determining VO2 max.”
10. Final Insights: Sustaining Health Through Exercise
Concluding the discussion, Dr. Levine reiterates the importance of integrating varied exercise routines into daily life to maintain cardiovascular health and delay heart aging. He emphasizes that while exercise cannot completely halt the aging process, it significantly enhances health span and functional capacity.
Dr. Levine [103:24]: “We have to include women in all our studies. It is essential. But I don't think women should think they are special in terms of their adaptation to exercise.”
Key Takeaways:
- Consistency Matters: Exercising four to five days a week is essential for preventing heart aging.
- Balanced Exercise Regimen: Incorporate a mix of high-intensity, moderate-intensity, and strength training for optimal heart health.
- Recovery is Crucial: Adequate rest between intense workouts prevents overtraining and supports cardiovascular adaptations.
- Understand Risks: While extreme endurance exercise may carry some risks, the overall benefits of regular physical activity far outweigh potential downsides for most individuals.
- VO2 Max as a Health Marker: Higher VO2 max correlates with lower mortality, making it a valuable indicator of cardiovascular fitness and longevity.
Dr. Benjamin Levine's research underscores the profound impact of structured, consistent exercise on reversing aspects of heart aging. By adopting a well-rounded exercise routine and prioritizing recovery, individuals can significantly enhance their cardiovascular health and extend their health span.