ACE Personal Trainer Practice Exam 2026 – 400 Free Practice Questions to Pass the Exam

The engagement of clients in aerobic interval training occurs primarily during the Aerobic Efficiency Training phase. This phase focuses on improving the body's ability to utilize oxygen more efficiently, which can be achieved through higher-intensity intervals.

In this phase, clients are typically able to handle bouts of higher intensity activity interspersed with lower-intensity recovery periods. These intervals allow for an increase in cardiovascular fitness while preparing the body for more advanced training. Aerobic interval training effectively enhances aerobic capacity and contributes to overall fitness progression.

The other phases each have distinct training goals that do not focus on interval training in the same manner. During Aerobic Base Training, the emphasis is on building a foundation of fitness with steady-state aerobic activities. Aerobic Endurance Training works on increasing overall endurance through longer continuous workouts, while Aerobic Power Training focuses on developing the ability to sustain higher intensity efforts for short periods. These training goals do not prioritize the interval training structure as seen in the Aerobic Efficiency Training phase.