Because they use oxygen to let the muscle generate energy.

At the beginning of cardio exercises, glycogen gets divided in order to make glucose but if there is absolutely no glucose present, it would result in fat beginning to decompose. The decomposition of fat is a process that takes its period and also bring about performance levels going down. When the physical body starts to use extra fat as a fuel, it causes what marathon runners call hitting the wall. There are numerous of different types of cardio exercises and the normal aerobic exercises are ones that are performed at degrees of intensity which may be termed high and for a long time.Bureau of Mines there are about 100 mineral fibers that are ‘asbestos-like’ fibers but only six of them are recognized and regulated by the US government. When mentioning asbestos, most of the time these 6 fibrous minerals are being referred to. The six asbestos minerals recognized by the government are: – tremolite asbestos – actinolite asbestos, – anthophyllite asbestos, – chrysotile asbestos, – amosite asbestos, – crocidolite asbestos. These six types are broadly classified into two groups: 1 Serpentine group consisting only of the chrysolite asbestos , 2 Amphibole group consisting of the remaining five different asbestos.