Not pulling more weight than you weigh is one nugget of wisdom that fitness-guru Lyle gives some of the E.T.A.students who visit him: "His big [nugget of wisdom] for a long time was: 'And the Lord said: Let not the weight thou wouldst pull to thyself exceed thine own weight'" (128).
Pages 138-140 feature the urban legend of a bricklayer who, being attached to one end of a rope, is flung about because of the pile of bricks (which is heavier than him) attached to the other.
When Gately is in the hospital and figures that he might die, he claims that the feeling of impending death "[isn't] calm and peaceful like alleged. It [is] more like trying to pull something heavier than you" (973).
It might also relate to the sign on the ETA's milk dispenser, which says "MILK IS FILLING; DRINK WHAT YOU TAKE" (631). The fact that it's in all caps stands out, much the way the different font of the bricklayer memo stands out. While such a sign would most likely say "MILK IS FILLING; TAKE ONLY WHAT YOU CAN DRINK," Wallace flips the second part, making an interesting statement about consumption as well as mother/child relations in the novel's America. The fact that the tennis players drink corporate, powdered milk also reinforces the idea of humans as robotic, consumption machines, particularly Trevor Axford.
The Weight of the Novel Itself
At a meta-level, the novel's weight physically illustrates one of Wallace's key themes: flipping between the narrative and endnotes is not at all unlike the bricklayer moving disastrously up and down the pulley system.
Stephen Burns writes that with regards to Infinite Jest "Wallace's publishers recognized its mass as potential selling-point... Frank Bruni quotes Little, Brown's head of marketing, who revealed that they planned to play the novel's size as indicative of its importance: 'the size lent a certain weight to the book'" (66-7). Although this is obviously a marketing ploy, it does hold truth. The novel's physical size is daunting, but is also a main reason why many people pick it up, perhaps on the (often false, but n this case [in my opnion] true) assumption that physical heft corresponds to intellectual, literary, and in Wallace's case, emotional, spiritual and psychic substance. The novel's length places it inherently in the Big Books category alongside Ulysses, The Brothers Karamazov, and the like, as a novel people want to read, if only to say they did.