In this METABOLIC EXERCISE mini course, we will discuss how different exercise intensities work together to fill in bottlenecks of your metabolic flow for maximal efficiency in training adaptation to get the most out of your effort.
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In this METABOLIC EXERCISE mini course: every system works efficiently when supply and demand are matched. Cardiovascular fitness determines your supply, muscle fitness your demand, and how much you move throughout the day how much you keep your engine idling. Endurance, strength, and regularity of movement therefore contribute to entirely different aspects of your metabolic flow.
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In this METABOLIC EXERCISE mini course: recovery from exercise benefits your fitness and health, whereas the exercise itself damages your body. Without recovering from and adapting to the exercise insult, it is just an insult that actually lowers your body’s ability to burn both sugars and fats compared to doing nothing at all: see the graph in the thumbnail published in Cell Metabolism.
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In this METABOLIC EXERCISE mini course: strengthening and high-intensity training create an adaptation to increased demand, whereas endurance exercise increases the efficiency of supply. The type of exercise that will increase your metabolic rate the most is therefore dependent on what aspect of your supply-demand fitness is most lacking. If it is the Caloric demand, strengthening will help you more. If it is the supply of nutrients and oxygen, the supply (cardio) will help you more. If it is that you are sedentary most of the day (regardless of how hard you exercise), then it is regular muscle activation throughout the day that will keep your muscles idling instead of completely shutting down that should be your focus. What helps you the most is fixing whatever is your metabolic bottleneck.
Step 4 of 6
In this METABOLIC EXERCISE mini course: Endurance exercise has four training zones. The lowest intensity can be maintained for well over an hour and is the best for the cardiovascular system because it causes minimal insult requiring recovery. The highest intensity you could maintain for about one hour is the “threshold” intensity that triggers the fight-flight system to increase fitness adaptation. The 10-minute intensity maximizes the delivery and use of oxygen, and therefore fats; I call this “long sprints.” The 1-minute intensity (anything less than about 3 min) triggers ATP loss in muscles, activation AMPK, increasing fat burning for the next several days. This is why HIT, HIIT, or “sprints” increase fat burning so much after exercise even though they mostly burn sugars during the exercise itself.
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In this METABOLIC EXERCISE mini course: strengthening also has four training zones, just like endurance exercise. The highest power output is not at the highest resistance, but rather the highest resistance at which you can maintain your normal movement cadence (movement rate), which generates the greatest POWER output. Higher resistance generally forces you to move against the resistance a bit slower, so this maximizes FORCE (instead of power). Power is your functional athletic work capacity, whereas your maximum force is your maximum strength. Higher repetitions, (against lower resistance) greater than 10 repetitions per set increase the muscle’s ability to efficiently use fuel, which is “muscular endurance.” As resistance lowers further, the number of repetitions per set goes to dozens or even hundreds, slowly increasing the contribution of cardiovascular endurance to the muscular endurance adaptation.
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In this METABOLIC EXERCISE mini course: movement, meaning any muscle activation, or even just muscle activation without obviously moving, pulls the motor proteins (myosin) out of the super relaxed state (SRX). The SRX is when the motor proteins bind to each other and therefore stop idling as they burn Calories. Activating muscle pulls the motor proteins out of the SRX so they are ready to activate movement again, which is the “twitch potential” that makes a warm up so critical to having full force output in the first repetition of a working set. Activating muscle (even if you don’t stand up out of a chair) keeps muscle idling for as much as an hour afterwards, burning more Calories that entire time. This video provides practical guidelines for implementing the minimal recommendations for strength and endurance exercise, as well as regular movement through the day.