If weight-loss is the goal of your workout, then finding and maintaining your workout in that zone will optimize the amount of fat you burn in your workout session. Steepshot | IPFS | Google Play

When you exercise within your Fat Burner Zone, about 50% of all burned calories come from stored energy, aka 'fat reserves'. However, at higher intensity exercise only around 40% of all burned calories

One of the most important reasons to exercise are the immediate effects on the brain. A single workout session immediately increases the amount of neurotransmitters like dopamine, serotonin, and noradrenaline.