National Academy of Sports Medicine (NASM) Performance Enhancement Specialist (PES) certification Practice Exam

The recommended intensity range for resistance exercises aimed at hypertrophy is typically 75-85% of an individual's one-repetition maximum (1RM). Training within this intensity range is effective for stimulating muscle growth because it creates sufficient mechanical tension and metabolic stress, both of which are key factors in promoting hypertrophic adaptations.

At 75-85% of 1RM, the weight is heavy enough to challenge the muscles significantly while still allowing for a moderate number of repetitions, typically between 6 to 12 reps per set. This range strikes a balance between volume and intensity, facilitating the optimal sarcoplasmic and myofibrillar hypertrophy desired in bodybuilding and strength training contexts.

Other intensity ranges, such as 50-65% or 65-75%, while beneficial for other training adaptations like muscular endurance or initial strength gains, may not provide the same level of stimulus required for maximal hypertrophy. The higher range of 85-95% would typically be associated with training focused on strength or power, which emphasizes lower repetitions and higher loads, making it less ideal for hypertrophic goals.