Here’s my protein ‘recipe’ for a less painful workout and overall strength:

During the day, 1g protein/ lb bodyweight.

3-5g creatine 30 minutes before working out.

1/2 to 1 ‘serving’ of a BCAA supplement (leucine, isoleucine, and valine) up to 30 after working out.
Other amino acids can actually interfere w/ BCAA effectiveness, so I avoid the ‘extra mega everything’ kinds of supplements.

At bedtime, 1 serving of a casein protein shake. Adding it can improve muscle building, and casein is slow-digesting so in theory better for overnight recovery than a faster digesting one.

Oh, and I’ve gained about 2kg while wearing looser clothing. I have measurable strength gains in the last couple of months.