Zone 2 Training Benefits

Zone 2 Training

Over the past year or so wearable health technology like a fitbit, Apple Watch or Garmin shows you which training zone you are in currently while exercising. There is a popular movement among endurance athletes towards aiming for ‘zone 2’ training. Zone 2 refers to a level of activity that requires 60-70% of your maximum heart rate, or light to moderate effort as you move. A fast walk or slow jog may be enough for you to get into this zone. 

Physiologically, to be active your body draws on adenosine triphosphate (ATP) to power your muscles and produce movement. To create ATP, your body uses two main energy systems: a slower oxygen requiring system (aerobic) and a faster non-oxygen requiring system (anaerobic). Although both systems are always working in your body, your aerobic system is your main source of ATP, and is most active at lighter intensity. The shift to primarily using the anaerobic system happens at very high, almost maximal exercise. When you are using this system you will know because you will be gasping for breath, and your muscles will often feel a painful, fatigue burning sensation. You are only able to rely primarily on the anaerobic systems for short periods of time, e.g. a final sprint to the finish line and a pedal up a short steep hill.

Why Zone 2?

Although it is tempting to prioritize exercise that leaves you gasping for breath and dripping in sweat, high intensity training may not be optimal for long term functional gains. With longer duration lighter training loads, your body improves its aerobic capacity - your ability to efficiently use oxygen to produce energy. This means that over time, you will be able to produce more energy at a lower effort. This also means that you can gradually improve your non-oxygen threshold, meaning that you can go faster/harder before you shift to anaerobic energy production.

Zone 2 training for a few months will start this shift of numerous improved physiological functions, faster metabolism and reduced injury risk. Finally, athletes who did the majority (~80%) of their training in zone 2 found that they had improved performance during competition. If you’re looking for a new focus in your physical activity, why not give zone 2 training a try and see how it benefits you?