hmmmmm no wonder yr only benching 105kg
Caffeine is a band aid solution, nothing can replace a balanced diet and rest.
Good advice,here is your best advice.
Forget about what everyone says and claims.
Do YOUR OWN RESEARCH.
Learn about clinically proven ingredients that can help "supplement" your training and diet. Look for supplements that have these clinically proven ingredients at the proper dosages.
Remember, that everyone responds differently to training, diet and supplements. you must try it out, and listen to your body.
best of luck!