The tl;dr is: 1. Apart from ADHD medications, which are very powerful, most drugs and weird obscure supplements have little effect (there are some intriguing but noisy results about peptides). 2. Exercise— especially weightlifting and HIIT— is also very powerful. There's evidence of a dose-response curve where light exercise is good but intense is better. Arguably this is pretty unsurprising, from an evolutionary per…
Also a blind study with these would be hard, as Modafinil has a noticeable effect on heart rate and blood pressure, and general response to stress (at least in my case), and also causes a distinct chemical smell of one's urine.