Final answer:
To train for muscular endurance, you should perform 12-15 reps at 60-70% of your max, which helps muscles adapt to sustained effort and improves their ability to contract over a long period without fatigue.
Step-by-step explanation:
If you wanted to strength train specifically for muscular endurance, the suggested approach is to perform 12-15 reps at 60-70% of your max. This rep range and intensity level is ideal for improving the ability of a muscle to continue to contract over a long duration without fatigue. When training for muscular endurance, the goal isn't to lift the heaviest weight possible but to increase the time your muscles can perform a certain action.
For instance, when you're lifting weights as part of an endurance-focused program, you're not necessarily trying to increase your max lift or muscle size significantly. Rather, you're aiming to complete more repetitions with a moderate load. This approach helps your muscles adapt to sustained effort, which is beneficial for activities that require long-term muscle contractions.