Science In Strides
In the world of fitness, the term “training zones” can often seem daunting, encapsulating a range of intensities and outcomes. Today, we’re spotlighting the unsung hero of these zones — Zone 2.
Why?
Because mastering this zone is akin to unlocking a hidden trove of long-term health benefits. The capacity of an athlete to engage in exercise is predicated on their ability to convert chemical energy into mechanical energy. This process requires muscle to produce ATP, the chemical energy necessary for muscle contraction which is mechanical energy. ATP can be synthesized through anaerobic or aerobic metabolism, utilizing fats and carbohydrates as its primary sources.
The intensity of the exercise determines whether fats or carbohydrates are used as the substrate and which energy system will dominate to produce ATP. This is where training zones come into play. Typically, at 55-75% of VO2 max intensity, and individual can generate ATP primarily from fats, known as the “fat-burning zone.” Above 75% of VO2max, carbohydrates become the main substrate because they can produce ATP more rapidly.
Enter Zone 2 training.
Remarkably, in the regimens of most professional endurance athletes, 60-75% of their training falls within this zone. The adage “slow is smooth, smooth is fast” is often cited in weightlifting, but applies here too. Developing a strong aerobic foundation will lead to more significant metabolic benefits and enhanced speed in the future.
Zone 2 training is effective because it enhances the number and efficiency of mitochondria as well as metabolic flexibility, which is why it boosts longevity and overall health. Mitochondria, often described as the cell’s “powerhouse,” are responsible for energy production. Therefore, more mitochondria equate to a greater ability to process glucose and fats. Metabolic flexibility refers to the mitochondria’s capacity to metabolize both fats and glucose. In many metabolic diseases, compromised mitochondrial function can lead to insulin resistance and eventually diabetes. This understanding may explain why extensive cardio and high-intensity interval training might not yield the fat loss one might expect.
Each training methodology has its place and discerning when and how to use them is a key to achieving desired outcomes.
Zone 2 training is not only advantageous for improving your training capabilities, but also beneficial for your long-term health and longevity.
Determining Your Zone 2
Find your heart rate max
HRmax = 207 - (0.7)(age)
Find your heart rate reserve
HRR = HRmax - resting HR
70% of your heart rate reserve is the best estimate for the upper limit of your Zone 2 HR.
Zone 2 upper threshold = 0.7 x HRR + resting HR
Example
Find your max heart rate by this formula
HR max = 207 - (0.7)(26) = ~189 BPM
Find your heart rate reserve
HRR = 189-67 = 122 BPM
Zone 2 upper limit
0.7 x 122 + 67 = ~152 BPM
Looking at the example, once my heart rate goes above roughly 150 - 152 BPM, I am no longer in zone 2 training and my body will go from using fat as its main energy source to carbohydrates.
Now that you’ve calculated the Zone 2 threshold, how do you put it into practical use?
Beginners: spend at least 30 minutes at a time at zone 2
Well Conditioned Athletes: 1-1.5 hours at a time
Aim for 3 days of zone 2 training per week for optimal benefits.
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Curious to experience the zone 2 difference for yourself? Strap on your heart rate monitor and take a step towards healthier training.
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Read to level up your cardio and longevity?
Zone 2 training isn’t just for endurance athletes — it’s a performance and health game-changer for lifters, fighters, and weekend warriors alike. If you’e ready t build an aerobic base without sacrificing strength, get started by emailing me at ThreeWrightLights@gmail.com or DM me “Zone 2 Program” on Instagram @ThreeWrightLights to learn more!
