Taking a preworkout AND carnitine? It is important to get the timing of each supplement right to get the best results with both. Watch as Phil explains the best way to combine them. , #preworkout Oxyenergys L Carnitine. My go to pre post workout supplement. Pre workout I usually take it before my workout session for energy production. Post workout Ill take it the day after my workout Liquid L Carnitine Energy, Metabolism & Fat Burning L Carnitine Amazon.com: PROSUPPS L Carnitine 3000 Stimulant Free Liquid Shots (31 Servings, Berry) and Mr. Hyde Signature Series Pre Workout Energy Powdered Drink (30 Servings, Watermelon) Bundle : Health & Household