Just about every training course written in the early 20th century promoted high-rep exercises using light weight dumbbells or other similarly “light” equipment (if they included any equipment at all — most did not.)
The Henry Higgins Strength and Muscle Course, however, was written somewhere around 1915 and is one of the earliest — if not THE earliest — training course to promote the lifting of heavy weights for the purpose of building great strength.
Henry Higgins, a famous gym owner in the New England area, is said to have met and discussed training methods with such famous oldtime strongmen as Eugen Sandow, Louis Cyr, Franz “Cyclops” Bienkowski, Samson, and Walter Kennedy (among others.)
In fact, using the training methods outlined in this course, the author is said to have once “put up” 254 lbs. with one hand. Higgins also trained a 20 year old Harvard medical student to do a one-hand dumbbell lift of 211 lbs. (at a bodyweight of only 145 lbs.) Another medical student who trained with Higgins succeeded with a 225 lb. lift. With nothing more than a set of gradual, adjustable dumbbells, the author guarantees that his training methods will enable the average trainee to clean and press a 140 lb. dumbbell in less than a year’s time!