What is Zone 2 Running?
Running at 60-70% of your heart rate maximum.
Aerobic Adaptations:
- Zone 2 running primarily targets the aerobic energy system, which relies on oxygen to produce energy.
- During this your body increases the delivery of oxygen to working muscles through enhanced cardiac output (heart rate and stroke volume) and improved blood flow to muscles.
- This leads to adaptations such as
- Increased capillarisation (more tiny blood vessels in muscles)
- Mitochondrial density (the powerhouse of cells), which improve your muscles' ability to utilise oxygen efficiently.
Fat Utilisation:
- In Zone 2, your body relies more on fat as a fuel source.
- Aerobic metabolism of fat = sustained energy supply without producing as much lactic acid.
- Training in Zone 2 encourages the body to become more efficient at mobilising and oxidising fat, which can be beneficial for endurance events where glycogen depletion is a concern.
Mitochondrial Biogenesis:
- Mitochondria are the cellular organelles responsible for generating energy in the form of ATP.
- Zone 2 running promotes mitochondrial biogenesis
- the process by which new mitochondria are formed within muscle cells.
- This adaptation
- increases the capacity for aerobic metabolism
- allowing for greater energy production and improved endurance performance.
