You go to the gym with one end goal: to build muscle strength. You start to lift your dumbbells and ask yourself how many reps you're "supposed" to do. In a new video from Picture Fit, a YouTube channel dedicated to health and fitness, the answer comes down to your goals, whether it's to build strength, to build muscle, or increase muscle endurance.

To build strength, completing around 1 to 5 reps can stimulate a more efficient neuromuscular drive, (better signal firing rates from the brain to the muscle) and myofibrillar hypertrophy (more force-generation components in muscle fiber known as actin and myosin) for stronger muscles. Picture Fit suggests going at a quick temp, such as a 1-second down and 1-second up cadence, and resting at least 3 minutes in between reps.

Six to 12 is the recommended reps for muscle growth; this range stimulates myofibrillar hypertrophy, too, but not to its full potential. Instead, it stimulates another type of hypertrophy known as sarcoplasmic hypertrophy. This fuels the muscle cell with more cellular fluid, called glycogen (aka stored carbohydrates), and more organelles. Most of these mean a larger albeit not technically stronger muscle.

This may explain why bodybuilders have larger muscles, but are typically weaker compared to professional weight lifters. Doing these reps at a slow and controlled tempo, such as 3-seconds down and 2-seconds up with no more than 90 seconds rest in between reps, is recommended for those focused on growth.

Lastly, if you're looking for more endurance in your workout, it's recommended to do high-intensity reps. This range can be anywhere between 15 to upward 100 reps, and will typically stress out your energy system rather than the muscle itself. This will allow the body to become more energy efficient by adapting to the metabolic stress. High-rep endurance training might not help you lift heavier, but you will be able to lift lighter weights for much longer while using less energy.

Remember, when choosing a rep range, make sure you also choose an appropriate weight. If you feel like you can do at least 3 more reps toward the end of your set, pick up something heavier; if you can't, go lighter.