Traps and Deadlifts
Have you ever woken up with sore biceps after a day in which you moved? Thinking back upon the loading and unloading of heavy furniture, you recall your arms being at a 90-degree, locked (isometric) position in order to carry couches up and down stairs and throughout rooms. Although you weren't performing bicep curls with a repeated up and down motion, you were still demanding a lot of work from these muscles through prolonged, strenuous contraction.
(This is our long-winded intro to why deadlifting builds the traps...)
Do you want strong, well-developed traps? (Traps are the new abs. Why wouldn't you want them to be bigger and better?!) Then you must deadlift! Deadlifting arguably helps develop this 3-part muscle more than any other lift on the planet.
The traps, like the biceps in the above example, must operate in a similar manner during this lift. The large muscle group, through isometric contraction, must withstand large amounts of weight pulling down on it and transfer force from the lower back up through the shoulders. They are liken to a beam supporting a bridge. The accumulation of reps, sets, and weight mean greater work; greater work results in a larger, more well-developed support beam for the body -- bigger, better traps!
So the next time you're picking up hundreds of pounds from the floor, just remember, your upper body is doing just as much work as your lower body. The deadlift is a valuable strength- and muscle-building tool for the traps.