Muscular Strength, Power and Endurance: What's the Difference?

Strength and power are two types of muscular abilities that are sometimes used interchangeably. But though they're similar, there are distinctions when you say someone is strong versus powerful.

Strength is the ability to move heavy weight and power is the ability to move weight with speed.

Another type of muscular ability is endurance, or the ability to perform many repetitions of an exercise.

Understanding the difference between strength, power and endurance can help you select exercises and strategies to achieve your fitness goals.

While excelling in some sports requires a greater proportion of one type of muscular ability, most sports require all three. Your ability to move weight, move it with speed and continue moving it for extended periods of time will help you be a better all-around athlete.

The definition of muscular strength is a muscle's capacity to exert brute force against resistance. Your ability to bench press a barbell weighing 200 pounds for one repetition is a measure of your muscular strength. In daily life, you need muscular strength to, say, pick up a heavy box.

Strength versus power: The two are often confused, but the main difference is speed, according to ExRx.net. Unlike power, strength requires no quick movements to produce force and is instead expressed by slower, controlled movements.

For example, a strong person may take 3 to 5 seconds to stand up during a barbell squat, but a powerful person can stand back up in 1 second. The most common sports where strength is required include weightlifting, football, wrestling, boxing, track and field and rowing.

Strength can be measured based on the amount of weight lifted for a single rep. This is referred to as a one-rep max, or 1RM. Upper-body and lower-body strength are measured separately. Strength tests include the bench press for upper body, the squat for lower body and the deadlift for lower back and leg assessments.

Relative strength is a measure of strength based on body size, expressed by a ratio of weight lifted to body weight. For example, if two people lifted the same weight, the person who weighs less has greater relative strength.

Adding a dose of speed to strength can make you feel like superhero performing superhuman feats. But being strong doesn't always translate to being powerful. According to Sports Fitness Advisor, you can be exceptionally strong, but if you cannot contract your muscles quickly, then you're not powerful.

The definition of muscular power is explosiveness, the ability to move weight with speed, according to the American Council on Exercise (ACE). For example, a strong lower body can do a heavy squat slowly, but it can't necessarily generate the power to do the same lift with speed. The definition of power is producing the greatest amount of force in the shortest possible time.

With the exception of powerlifting, most power exercises — vertical jumps, lateral hops, kettlebell swings and more — are performed repetitively to improve speed, stamina and reflexes. Common power sports include Olympic weightlifting, track and field, boxing, football and ice hockey.

Muscular endurance is strength over time, and it refers to the ability to perform a specific muscular action for a prolonged period of time. For example, your ability to run a marathon or to pump out 50 body-weight squats is a product of good muscular endurance. (The difference between muscular strength and muscular endurance is the amount of weight you can lift versus how many times you can move that weight without tiring.)

You also use muscular endurance in your daily life when you rake leaves or walk up long flights of stairs.

Endurance sports include distance cycling and running, track and field, swimming, skiing and rowing.

Endurance training has significant cardiovascular health benefits over resistance, or strength training. Though both increase your maximum oxygen uptake, the increases from strength training are less.

Also, though endurance training leads to decreases in resting heart rate and in systolic and diastolic blood pressure, strength training has little effect on them. Both may be incorporated into treatment and prevention programs for diabetes, and both can be used to increase metabolism and reduce weight.

Despite such benefits of strength training, the sharp increase in blood pressure after single-repetition exercises may be dangerous if you have a cardiovascular condition. Talk to your doctor before taking on a strength or endurance training program.

Strength training alone can only get you so far in maximizing your athletic abilities. While you can build strength without higher power training, you're less likely to gain power with only strength training. So if you're doing activities that require quick bursts of energy (sprinting, HIIT, etc.), you should combine muscular strength and power training.

In a notable June 2007 study in ‌Medicine and Science in Sports and Exercise‌, researchers found that subjects who performed 12 weeks of power and strength training had greater improvements in jump height and more power output in jump squats than those who just did strength training.

But training is also sport-specific, not one-size-fits-all. Your individual training program should reflect the weight and rep demands of your sport or fitness goals. It can be helpful to consult a coach or personal trainer to get help assessing your strength, power and endurance. They can also help you set reasonable goals and provide you with a training plan for reaching them.

Training is specific to your goals, per the ACE. The number of sets, reps and speed will vary between strength, power and endurance training.

Building strength requires progressive overload (gradually increasing the amount of resistance) at a higher weight and lower reps, performed with control. Aim for 2 to 6 sets of 1 to 5 reps with a lifting intensity of 85 to 100 percent of your 1RM, according to the NASM. Take longer rest periods between sets — 2 to 5 minutes — to give your muscles a chance to recover and prepare for the next set.

Power training is similar to strength training, but the speed is increased and there's less rest between sets. You'll perform explosive movements geared to specific skill development.

You may also use supersets or circuits, which are a series of 2 to 5 muscular strength and power moves performed back-to-back. A general goal is 3 to 5 sets of 1 to 3 reps at 80 to 85 percent of your 1RM.

Endurance training is based on progressively increasing the time you do an exercise. Workouts consist of lower weights and higher reps, typically 3 sets of 15 to 25 reps at 20 to 70 percent of your 1RM. Shorter rest periods between sets — 30 to 60 seconds — increase fatigue levels for the next set and help improve your endurance over time.

Putting emphasis on strength, power or endurance training depends on your goals. Certain athletes, such as powerlifters, football players and rugby players, need strength and bulk to perform their sports.

Athletes such as tennis players, basketball players and martial artists are best served by focusing on both endurance and strength training. They need power in short spurts to return a shot or sprint down a court.

Endurance training is best for triathletes, distance runners and rowers.