The slow twitch muscle fibres have a higher count of mitochondria which means it can process quicker, it receives a energy, it receives a good blood supply since it has a high amount of capillaries, which means it has a good supply of oxygen, which helps to maintain the use of the aerobic energy system for longer, making type 1 fibres more effect for endurance, while the type 2 fast twitch have less mitochondria and rely more on glycolysis.