One leaves you breathless, the other requires no breath, lol... Aerobic exercise requires oxygen to produce the energy for the workout, increases the cardiovascular capacity, increases the heart rate, will help burn fat at low intensity (e.g.- walking), will burn more carbs at high-intensity, isn't ideal for building muscle, but is good for getting toned. Anaerobic exercise has more to do with working the specific muscles and not so much with pushing oxygen to those muscles in order to perform. Weight training is the primary example of this, where cardiovascular endurance isn't required. This helps with building muscle, burning fat, and increasing strength. For me personally, as much as I want to get bigger muscles, I also get a serotonin boost when I complete a 5 or 10k, a long bike ride, or a strenuous mountain hike, meaning I need a balance of the two. To attain this balance, I moderate my approach to my bootcamps, sometimes minimizing the effort for the cardio and increasing the weights for the strength components, and then I make an effort to spend some time strictly lifting as well with no cardio. Besides, if I do the workout correctly with the intention of losing fat and building muscle, while putting efforts for my cardiovascular wellness, I'll still be on the floor at the end of it catching my breath (haha!)