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.