Why Cardiovascular Training Matters for Strength, Recovery & Longevity

The Vitality Collective Podcast is a health and fitness podcast focused on strength, longevity, and real-world performance, bridging the gap between health and performance. Hosted by Dr. Jeremy Bettle, PhD—an internationally recognized expert in Human Performance with over 20 years of experience working with elite athletes and high performers—this podcast brings world-class expertise straight to you. Built from elite sport and applied to real life, it breaks down what actually drives resilience, health, performance, and long-term capability. Designed for high performers, professionals, and anyone who wants to stay strong, capable, and injury-free while balancing real life. This health and wellness podcast explores how to build strength, prevent injury, improve cardiovascular fitness, optimize sleep and nutrition, support cognitive performance and brain health, and maintain emotional and social well-being through expert interviews, applied breakdowns, and proactive, real-world strategies. Whether you're training, recovering from injury, or trying to stay consistent while balancing work, family, and life, this podcast gives you a clear, practical path forward.   Guest Bio Dr. Mike Axler is an Assistant Professor of Exercise Science with a PhD in Kinesiology and Applied Physiology. He brings a unique blend of academic expertise and real-world performance experience, having worked as a Division I strength and conditioning coach while also competing in nearly 70 marathons and 20 ultramarathons. Mike is the founder of Axler Concierge Coaching and the host of the Simple Science Podcast, where he breaks down complex topics in exercise, nutrition, and human performance into practical, actionable insights. His research focuses on nutritional epidemiology and applied physiology, with ongoing collaborations spanning wearable technology companies and clinical settings. Driven by both curiosity and personal challenge, he is currently pursuing the goal of running marathons in all 50 U.S. states and on every continent. Links Simple Science Podcast: YouTube Spotify Instagram: @mikeaxler.phd Three Actionable Takeaways Do something physically challenging today that is slightly harder than yesterday. It does not have to be dramatic. If you walked 4,000 steps yesterday, walk 4,050 today. If you ran a six-minute mile, try for 5:59. Progress is the direction, not the distance. Challenge your mind with something new and unfamiliar every day. Ask an AI for a random fact, learn how to say a word in another language, or try a physical skill you have not done before. Neuroplasticity requires novelty and effort. Every time you sit down to eat, put a protein source and a fruit or vegetable on your plate alongside whatever else you are having. You do not have to overhaul your diet. Just anchor every meal to those two things. Key Insights The ATP-PC (phospholytic) system powers the first roughly 10 seconds of any maximal effort. After that, the glycolytic system takes over. The aerobic system becomes dominant when intensity drops to a level the body can sustain -- and it is the only system that runs on stored fat. Aerobic training builds mitochondrial density and capillary density inside muscle fibers. More and healthier mitochondria mean faster ATP regeneration during rest intervals, which translates directly to shorter recovery time between strength sets. Cardiac output equals heart rate multiplied by stroke volume. Consistent zone two training increases left ventricular stroke volume, meaning the heart pumps more blood per beat and does not need to beat as fast. A lower resting heart rate is evidence of this adaptation -- and it compounds over decades. During aerobic exercise, the body draws on both stored glycogen and stored triglycerides (fat). During anaerobic exercise, it burns only carbohydrates.