ISSA Trainer Practice Exam 2026 – Complete Study Resource

Anaerobic exercise is characterized by the body's ability to perform work without relying on oxygen for energy production. This form of exercise typically occurs during high-intensity activities that last for a short duration, like sprinting or weightlifting. During these activities, the energy required is derived from the breakdown of glucose or creatine phosphate, which are stored in the muscles, rather than from oxygen-dependent metabolic pathways. As a result, anaerobic exercise leads to the accumulation of lactic acid due to the incomplete combustion of glucose, which can result in muscle fatigue.

Understanding this definition is crucial for fitness professionals as it helps them design effective training programs that utilize different energy systems based on the goals of their clients. By focusing on anaerobic exercise, trainers can help improve strength, power, and overall athletic performance for activities that require short bursts of energy.