Training should progress from highly general, such as lifting weights and cardio, to very specific so it includes performing that exercise or skill. To be a good cross country skier, you need to ski. Training mimics the action and skills that will be needed in the game or activity. Over time, you develop muscle memory for specific actions so you can perform them without having to concentrate on them. To give an example during her career Marit Bjørgen reported that around 60% of annual endurance and sprint training hours were ski specific (skiing on snow or roller skis), while the rest was primarily running with similar coordination and movements to skiing.
The LIT work focuses on technique so large quantities have benefits both in terms of capillary densification, which improves the supply of blood and oxygen to muscles and mitochondrial volume expansion giving improved energy storage, but also in improving skills associated with the activity.