Anaerobic strength is musculoskeletal force that does not require oxygen; energy for anaerobic strength comes primarily from the glycolytic pathway. It involves the development of severe oxygen debt, as the emphasis is on repetitive muscular capacity without entering into the aerobic phase of energetics. Examples of this are found in wrestling, boxing, and high-repetition training (greater than 20 reps). The two types of anaerobic strength are speed-endurance and strength-endurance.