Volume intervals require what?

The concept of volume intervals in fitness training specifically relates to the total amount of work performed, which is most commonly quantified by the number of repetitions of an exercise. Volume is a critical factor in resistance training and group fitness because it helps to determine the intensity and overall effectiveness of the workout.

When we look at volume intervals, they often emphasize the number of repetitions completed within a given timeframe or session. This allows trainers to structure their workouts to target specific fitness goals, such as building muscular endurance or increasing strength. Ensuring a specific number of repetitions can help achieve these goals by effectively challenging the muscles, while also allowing for systematic progression in a training program.

The other options do not align specifically with the definition of volume intervals. While the number of exercises could be important in a workout, volume intervals primarily focus on the repetitions. A fixed duration for the entire workout is more about the time aspect rather than volume, and while increased rest time might play a role in workout structure, it is not a requirement of volume intervals. Thus, focusing on a set number of repetitions of an exercise encapsulates the essence of what volume intervals require in a fitness context.