Muscle growth is a complex process, specially when you are just starting out. There’s a lot of information out there, and some of it contradicts itself, so it is not unusual to be confused about how you should go about it. One common misconception is that you should do a very high number of reps. This usually means that you will pick up lighter weights to do so. In reality it is better to do heavier loads of weight, for less repetitions.

High Reps vs Heavy Weight: The Science

To be able to see which of this tactics had better results, researches got together a group of young men and devised a program for them, which would test this two different tactics on each person’s two different legs. One leg would do lighter sets with higher number of repetitions, and the other heavier sets. This was done over 12 weeks.

Results found that both tactics had succeeded in increasing the muscle mass of the participants. However, they also observed that the leg that had done the heavier loads of weight for less repetitions had increase more muscle mass than the other. In fact, in any one of the participants, the legs with higher reps reported an muscle increase of 0.8%-2% while the ones with heavier weights 7%-14%.

With these results, it is clear that, if you are looking for efficiency, you should be doing heavier weights.

How to choose your weight

Now that we have ascertained that you should favour heavier weights, there’s only the question of how heavy should they be. A lot of beginners try to get someone who knows to tell them exactly how much they should be lifting, but the reality is that it is best for you to figure this out on your own. To do this is really simple: in any set, you should be doing 8-12 reps. No more, no less than that. If you are not able to do 8, then the weights are too heavy. If you are easily doing more than 12, increase your load.