National Academy of Sports Medicine (NASM) Group Fitness Instructor Practice Exam 2025 – All-in-One Guide to Achieve Certification Success!

The recommended repetition range for endurance training in a strength-based class is typically between 12 to 20 repetitions. This range is optimal for promoting muscular endurance, which is the ability of a muscle to sustain repeated contractions over time without fatigue.

When aiming for muscle endurance, the higher repetition ranges allow for lighter weights to be used, which reduces the risk of injury while still effectively challenging the muscles. This approach is particularly valuable in group fitness settings, where participants may have varying fitness levels and strengths.

Additionally, training in this repetition zone helps improve metabolic conditioning and promotes adaptations such as increased capillary density and enhanced oxidative capacity in the muscles. This is crucial for any group fitness instructor aiming to design classes that not only improve strength but also support participants' overall endurance and fitness goals.