People are often confused over how many reps to do in their workout routine.  The truth is, it really depends on what your goal is and what muscle group you’re targeting.

Generally, your workout routine should include some mixture of low repetition heavy weight sets and high repetition low weight sets. The number of repetitions should also vary depending on what muscle group you’re targeting. Exercises using muscle groups such as biceps, calves, and abdominals should usually make use of lighter weight for higher repetitions. On the other hand, exercises using larger muscle groups such as legs and back should usually make use of heavier weight for lower repetitions. That being said, three different training styles that incorporate different amounts of weight and repetitions will result in differing athletic ability and physical appearance.

Training for Endurance

Training for endurance is similar to performing an aerobic exercise. Focusing on muscle endurance means picking up lighter weights and performing the movement for 15-20 reps. Another difference is when training for endurance, rest periods are often very short (30-45 seconds) because the idea is to replicate the conditions the body will face during the sport or activity (e.g., marathon, tennis, hockey, hiking, etc.). Training with light weight for high repetitions also tones the body. If proper nutrition is paired with endurance training, muscles will appear firm and defined.

Training for Muscle Size

If you want to gain size, choose a weight that is suitable for 8-12 reps. But if you can easily breeze through 12 reps, it means you’ve chosen a weight that is too light, and if you’ve chosen a weight that you cannot perform six of, that means it’s too heavy.  The goal is to find a weight that is difficult, yet attainable, to push or pull 12 reps of. Rest periods should be no more than 1-2 minutes. Training for muscle size is usually accompanied by healthy weight gain and an increase in muscle density. The result is that muscles look larger and more firm.

Training for Strength

Although you will gain strength utilizing either style mentioned above, the best way to get very strong is to train with very heavy weight for low repetitions. The strongest powerlifters train by performing very heavy weight for low repetitions (usually 1-6 reps) with very long breaks in between (4-8 minutes). But be safe in your approach. Always choose a weight that is difficult, but that’s not going to compromise proper form. Using a heavier weight for a lower number of repetitions doesn’t tone or shape the body in the same way training for endurance or muscle size will. Training for strength will add muscle mass and change the shape of your body, but the change will be slightly less pronounced than other forms of training mentioned above.

Switch up Your Routine

After you’ve committed to a style of training, remember to change it up once in a while. If you’ve been training in an endurance-style for a month and a half, try adding a few sets of heavy weight with lower repetitions to your routine for a few weeks (and vise verse for strength trainers). Since your body will not be used to the change, it will be forced to grow and adapt, making you better along the way.