ACE Personal Trainer Practice Exam

What is the recommended resistance percentage range for inducing muscular hypertrophy?

1. 50-60% max resistance

2. 60-70% max resistance

3. 70-80% max resistance

4. 80-90% max resistance

The correct answer is: 70-80% max resistance

The recommended resistance percentage range for inducing muscular hypertrophy is generally considered to be between 70-80% of an individual's one-repetition maximum (1RM). At this intensity level, the muscle fibers are sufficiently recruited and stimulated to promote growth through increased tension and volume during resistance training. When training at 70-80% of maximum resistance, individuals typically perform between 6 to 12 repetitions per set. This rep range is effective for maximizing time under tension, which is a key factor in achieving hypertrophic adaptations, such as increased cross-sectional area of muscle fibers and enhanced metabolic processes within the muscle. Additionally, this resistance level facilitates a balance between mechanical tension and metabolic stress, both of which are important drivers of muscle growth. As a result, this range is well supported by both scientific research and practical application in strength training protocols aimed at increasing muscle size.