sensation, pump, soreness, feeling, orgasm, throbbing, twitching, pain are not indicator of growth.

Muscle size will increase as you become "stronger" in moderate rep ranges. For example, if you used to do 10 reps of 50 kg (110 lbs) on the bench press and by the end of the year you can do 100 kg (220 lbs) for 10 reps, your chest size will increase.

If you are lifting 20kg (44 lbs) for 10 reps today and 20kg (44 lbs) for 10 reps by the end of the year, you've made no progress, you'll see no muscle growth. You may have got leaner and see some definition but actual muscle size would have not changed

When should you add reps or weight to the bar? Every session? Every week? Or every month? Well, the goal isn’t to add something to the bar every week. Add weight or reps when you become comfortable with the load and it no longer serves as a "stimulus." You'll become comfortable with a load as adaptation occurs.

Suppose you're bench pressing 60kg (132 lbs) for 6–10 reps, stopping 2 reps shy of failure (2 RIR) each set. Over time, as you adapt, that same weight starts feeling easier. By the time you hit 10 reps, you're now 4 reps shy of failure (4 RIR) well beyond the recommended proximity to failure. The guideline calls for staying within 0–3 RIR to ensure sufficient stimulus for growth. At 4 RIR, the set loses its effectiveness. And since you're already at the top of your rep range (10 reps), you can't just add more reps. Instead, it's time to bump up the weight on the bar to restore that challenging edge. But if you were doing 9 sets at 4 RIR you'll respond by adding 1 more rep, making it 10 reps. This is basically "double progression", where you first add reps untill you reach the top of the recommended rep range, after that you add weight but only when the current set stops being sufficient training stimulus.

As you progress and grow stronger, you may only be able to add weight to the bar every few weeks or months. The goal is to become stronger over time in moderate rep ranges, and muscle size increase will come as a result of this.

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