This is one of the best ways to make muscle gains, especially in the context of getting stronger.

For each exercise, take a given weight and try to sustain it through the given rep ranges, for the entire number of sets.

If you have a main lift, where you also have sets of 3 repetitions, try and bump those up to 5 repetitions.

Here’s an example:

Exercise: Bench Press

Sets: 4 working sets

Reps: 5,5,3,3

Set 1 – 5 reps, 80 kg

Set 2 – 5 reps, 80 kg

Set 3 – 3 reps, 80 kg

Set 4 – 3 reps, 80 kg

As you progress through this lift, try to complete 4 sets of 5 reps with 80 kg (or whatever your working weight is), by increasing the reps from 3 to 4 and 5, in time, on the last two sets.

Once that happens, bump up the weight with 2-5 kg, and aim to progress up to 4 sets of 5 with that weight.

When you do that, odds are that you will be able to get 5 reps on your first set, followed by sets of 3-4 reps on the last sets.

In time however, you will gain strength and you will be able to increase the repetitions.