Because doing anaerobic first will consume a lot of glycogen and fat, and muscle glycogen is seriously insufficient at this time. If you do strength training, muscle glycogen can't be supplied and fat can't continue to provide you with energy. Well, at this time, the body will use protein to supply energy, and protein is part of the muscle. This is why you consume a lot of your free muscles to maintain the energy system. So don't do aerobics first, then do strength.
On the contrary, the body's glycogen is completely consumed by the pre-training strength, and the order of the body's energy supply system has directly entered the fat energy supply stage. Aerobic exercise began to consume a lot of fat to supply energy, which greatly kept the muscles from losing and consumed more fat.
Hope to help you, hope to adopt!