It seems odd...
that the dose wasn't pre-calculated based on population averages and simply adjusted once the subject's body mass was measured.
I used to do this sort of shit as a student during my first two years. It was mainly the RAF who were interested in the effects of various things that their pilots might get up to. I had to, on various occasions, not all at the same time, eat a 1kg bar of Dairy Milk / a carob alternative with a clothes peg on my nose so I couldn't tell the difference, drink 6 cups of tea (caffeinated or decaffeinated) in the hour prior to the test, drink 4 cups of coffee likewise, starve myself of all but water for 24 hours prior to the test, eat normally for 24 hours or overeat (they gave me a menu and a box of food for these), sleep for varying numbers of hours in the 48 hours before a standard reactions test and, for want of a better word, copulate at least 6 times in the 24 hours before the test, do it just the once, or abstain.
And when you're paid to take part in experiments like that as an impoverished student, you tend to take them up on the offer.
Biting the hand that feeds IT
