High-intensity interval training (HIIT) can lead to greater improvements in cardiorespiratory fitness and mitochondrial density compared to Zone 2 training.

“high-intensity AAL training workout that you're going to have even more improvements in cardiorespiratory Fitness than you would Zone to you can have better improvements in mitochondrial density for example than you would so it it's kind of interesting to look at the benefits of doing something like high intense interval training”