Pre-Workout

Three ingredients carry most of the evidence: caffeine at 3 to 6 milligrams per kilogram of bodyweight for output and perceived effort, beta-alanine at 3.2 to 6.4 grams daily for sets lasting one to four minutes, and citrulline malate at 6 to 8 grams for blood flow. Anything dosed below those thresholds, or hidden inside a proprietary blend, is there for the label.

Only a stimulant-free one. Caffeine has a half-life of roughly five to six hours, so a 6pm dose still has meaningful caffeine in your system at midnight. Lost sleep costs more than the session gains. Use a zero-stim pump product for evening training.

That is paraesthesia from beta-alanine. It is harmless, it fades with regular use, and it is unrelated to how well the product works. Splitting the dose reduces it.

Creatine. It builds genuine strength over weeks and works whether or not you feel anything. Pre-workout is an acute boost for the session in front of you. If you are buying one, buy creatine.

The ingredients are, but daily caffeine builds tolerance within two to three weeks. Cycle stimulant pre-workout to your two or three hardest sessions a week and train the rest without it.

Yes — the formulas are identical and the dosing is by bodyweight, not sex. Start with half a scoop to gauge caffeine tolerance.