What is the recommended load percentage for muscular endurance workouts?

• A. 70-85% of 1RM
• B. 40-50% of 1RM
• C. 60-70% of 1RM
• D. 20-30% of 1RM

Answer: (B)

Muscular endurance is built by training lighter loads for a higher number of repetitions, so the muscles learn to sustain work and resist fatigue over many contractions. Using around 40-50% of your 1RM lets you perform a high enough volume (often 12 or more reps per set) with good form while still challenging the muscles enough to provoke adaptations like improved fatigue resistance and local metabolic capacity. Heavier ranges, such as 60-70% or 70-85% of 1RM, are more effective for building strength and muscle size, not endurance, because they require fewer reps and recruit more fast-twitch fibers under heavier load. Very light ranges like 20-30% may be easy to perform and often don’t provide the stimulus needed for endurance adaptations in trained individuals. So the recommended load range for muscular endurance workouts is around 40-50% of 1RM.