Strength Training and Strength Endurance. What’s the Difference?

Strength Training and Strength Endurance. What’s the Difference?

When your goal is to increase strength, then strength training should be your primary training protocol. Strength training includes free weights, weight machines, body weight or resistance bands that helps build and maintain muscle mass and strength. Strength training also helps build strong bones, minimize the risk of fracture due to osteoporosis, improves heart health and helps with weight loss.

More and more group fitness classes have incorporated weights into their routines. From BodyPump to cycling classes, even Peloton programs, these type of group classes usually include light weights for a high rep count and sustained for a long period of time. This combination is often referred as strength training but is it really strength training? To answer this question, there are two types of training methodologies that need to be understood  – strength training and strength endurance.

Strength Training

Muscle strength, in scientific terms, is a measure of the greatest amount of force that muscles produce during a single maximal effort. In more simple terms, it’s the heaviest amount of weight you can lift or move. So how do you train your muscles to get stronger? This happens with repeated short term contractions against incremental loads. In other words, lifting heavy weights in a progressive manner. The process by which strength gains occur is a complicated physiological process. But in short, when load is applied, reactions occur within muscle cells that allow key muscle fibers to form new muscle fiber strands resulting in an increase in number and size of the muscle fibers. The more muscles fibers there are, the more can be recruited to produce more force, quicker. This recruitment is what helps in building strength.

In strength training, intensity, effort, low reps, progressions and working on the same lifts for the training cycle are important elements for adaptions to occur and to measure improvement. The weight should be challenging and repetitions should be kept to less than 12. Rest time is important and when the goal is to get stronger, research has shown that the appropriate rest time should be 3-5minutes between sets. This is because much of the energy your body consumes during traditional strength training (heavy weight, 8 or less reps) comes from the Adenosine Triphosphate Phosphocreatine system. The ATP-PC system uses phosphagens to produce energy very quickly and without the use of oxygen. Your body has a very small phosphagen reserve, which lasts about 15 seconds. It takes your body about 3 minutes to fully replenish phosphagen stores. And the amount of rest between sets is important as it can influence the efficiency, safety and ultimate effectiveness of a strength training program.

The adaptation of muscle to the overload stress of resistance exercise begins immediately after each exercise, but often takes 3 or more weeks to physically see changes.

Muscle/Strength Endurance

The strength endurance approach will focus on lifting light weights for high number of reps, non-stop and/or with very short rest periods. In technical terms, muscle endurance refers to the ability of a muscle to sustain repeated contractions against resistance for an extended period of time. This means the number of repetitions of a single exercise you can do without needing to stop and rest. While there is some resistance when lifting light weights for volume, this is working on an entirely different system – the cardiovascular system or more commonly known as cardio – improving the ability of the heart to deliver a steady supply of oxygen to working muscle and increasing capillary size to help the heart pump blood more efficiently. However, this doesn’t affect the number or thickness of muscle fibers which is needed for strength improvements.

This type of training usually involves reps of more than 15 with minimal rest or no rest. This increases your breathing and heart rate which is exactly what you need for weight loss! But if strength gains is what you are after, this is not what you want to do.

This isn’t to say that if you are beginner, you should start by trying to lift the heaviest weight possible to get stronger. Or that you should stay away from muscle endurance training if strength is your goal. Or that you should start fast and furious!

If you are a beginner, you will need to start with the appropriate weight to build up your strength without injuring yourself. This also gives you the opportunity to learn how to perfect your form when doing a particular lift. You may need to start with light weights and progressively increase as appropriate. Endurance workouts can help increase your stamina and reduce fatigue during your training. It should be tailored to your fitness level and you may need to start with short training sessions until your stamina and strength improve. A fitness professional can help you develop the best training plan for you.


Strength training and strength/muscle endurance are two very distinct training approaches with very different outcomes. When you include strength training in your exercise program, it helps you build lean muscle, it helps build strength and also improves your metabolism. Repetitions should be kept to less than 12, you should be resting between sets and weight should be progressively increased as you get stronger.

When working on muscle endurance, you are working on improving your conditioning. By lifting light weights and lifting it repetitiously for as long as you can do it, helps your heart get stronger, by pumping blood more efficiently. This approach may  improve muscle definition but does not significantly improve muscle strength. Health benefits associated with muscle endurance training include preventing chronic diseases such as diabetes, blood pressure, reducing your risk of a heart attack, making your immune system stronger, helps with your mood.

Therefore, any group classes that asks you to use light weights or any weights and lift it non stop or with very short rest periods, this is NOT strength training. Rather, it is muscle endurance. And muscle endurance isn’t the same as strength training.