Any advise when it comes to pre-workout supplements?

Pre-workout supplements are optional; prioritize good sleep, nutrition, and consistent training, and consider non-stimulant options if caffeine is undesirable—especially for late workouts. 1

1. Citrulline, arginine, nitric oxide, or beetroot: These can be alternatives to caffeine; beetroot has the most consistent evidence here, particularly for moderate- to longer-duration endurance performance. 2
2. Citrulline and cold sores: If you’re prone to cold sores, be cautious with citrulline—especially at high doses—because activating the arginine pathway may worsen them. 3
3. Alpha GPC and other nootropics: They may support focus, but human exercise-performance evidence is limited. Consider reserving them for especially challenging sessions rather than using them every workout. 4
4. Rhodiola: It may lessen perceived fatigue and support recovery. A typical amount discussed is 100–200 mg about 10–20 minutes before exercise; start with the lowest effective dose. 5