muscle strength is the repetitive movement by maxing what you can lift whereas muscle endurance is the repetitive movement by counting the number of reps
yes you should do both but after you have started training for at least a several weeks before maxing out; after the time has elapsed you test your RM and then 6-12 weeks into your workout you can retest yourself to check your progress
it is good to know where you stand in both of these categories not only to track your progress but to ensure that you are getting out of your workout what you intend to.
-strength training develops both muscular strength and endurance: when the muscles are stressed by a greater load than they are used to they adapt and improve their function (to get the most out of it design it to where you achieve maximum fitness benefits with minimum risk of injury)
-the American College of Sports Medicine recommends a frequency of at least two days per week for weight training; allowing your muscles at least one day of rest between workouts
- the amount of weight you lift in weight training exercises should be equivalent to intensity in cardiorespiratory endurance training
-choose a weight heavy enough to fatigue your muscles but light enough to complete the repetitions with good form
-fewer reps should be done with heavier weights and more reps with lighter weight