These supplements might contain things like caffeine, taurine, beta-alanine, creatine, things that end in 'een', chemicals that can make you more alert and get your blood pumping.
'No no, dunnot say that, sir. 'Tan't kep' up that way. Not that way. 'Tis kep' down that way. I'm a weaver, I were in a fact'ry when a chilt, but I ha' gotten een to see wi' and eern to year wi'.