As you start to learn more about fitness and resistance training, there can be a lot of terms and methods that are outright confusing. You may have heard about muscular strength and muscular endurance and found yourself wondering what exactly the difference is between the two, and you're not alone.
"Muscular strength is the maximal load that a muscle can move," Joseph Signorile, PhD, a professor in the department of kinesiology and sport sciences at the University of Miami, told POPSUGAR. It's measured with an isometric contraction (the muscle is activated, but it isn't lengthened or shortened, for example, holding a plank) or by someone performing a one-rep max (1RM), the heaviest weight they can lift for one rep, of a specific exercise, Dr. Signorile said.
"Muscular endurance is the amount of repetitions that an individual can do of any type of an activity . . . and the amount of fatigue they show in doing that number of repetitions," he explained. An example of muscular endurance would be seeing how many reps of squat jumps you can do nonstop before you are fatigued and have to stop.
If you're trying to improve your strength, Dr. Signorile recommends completing three to four sets of three to six reps per exercise for tissue adaptation, "where the muscle tissue and connective tissue can get used to the amount of weight that you're giving them." To prevent injury, the weight shouldn't be close to your 1RM when you begin to focus on strength, and it will vary from person to person. For muscle endurance, he recommends doing three to four sets of 20 reps, minimum, but this may also vary based on your physical abilities and the expert you work with.
Typically for strength, Ashley Fluger, CSCS, an exercise physiologist at the Hospital For Special Surgery's Tisch Sports Performance Center, said to focus on fewer reps, anywhere between eight and 10 reps, and for muscular endurance, higher repetitions in the 10- to 20-rep range.
Muscle strength and endurance are both very important to focus on, Fluger explained. You may focus on one more than the other, but that split will be contingent upon your needs and goals, Dr. Signorile said. He did explain that, "If an individual increases their muscle strength, they will increase their muscular endurance at the same weight that they're using." Fluger agreed, adding, "as you increase someone's muscular endurance, there also are strength gains."
When it comes to specific programming for workouts focused on muscular endurance and muscular strength, Fluger emphasized the importance of working with a professional to help you establish a baseline, in addition to completing a fitness assessment since everyone's physical ability and background vary.