Is there a magical rep range or workout routine?

Muscle growth: Most research shows that 6–20 reps per set is the most efficient way to build muscle, with bodybuilders often favoring 8–12 reps per set
Strength: 4–5 reps per set can help you get stronger
Endurance: 15–20 reps per set can help with endurance
Multi-joint movements: These movements recruit more muscle mass than single-joint moves, so you can lift heavier weights

If your objective is strength or power (think: heavy lifting), the textbook advice is to perform 3 to 5 sets of 2 to 6 reps per exercise. For hypertrophy (building muscle), the sweet spot is 3 to 4 sets of 6 to 12 reps. And if your objective is muscular endurance, shoot for 2 to 3 sets of 12 to 20 reps.

Is there a magical rep range or workout routine?

There is a fine line between both hi and low repetitions, and you should not always use high or heavy weights, because if you concentrate on only heavy weights then you will strangle your body. You need to chock your body with higher repetitions and lower weight on a two weeks off, two week off basis, what we mean is that you can use 2 weeks super heavy while you shift to a two week lighter weight training but with many more repetitions, you will see how your body react to this and you will be happy with the results!

If muscle growth is your main objective, then be sure that a good deal of your workouts are done using reps in the sweet spot for muscle growth—8-12 reps. That being said, you don’t want to ALWAYS train in the 8-12 rep range. Sticking with a rep range for too long will only lead to stagnation and limit your results. That is why you also need to train with heavy weight and lighter reps (fewer than 8 reps per set and as few as 2 per set) and also very light for higher reps (more than 12 reps and even as high as 30 reps on some sets) to keep progressing and keep muscles growing. Plus, using a wider range of reps provides your muscles and your overall body more benefits, like greater strength and greater endurance.