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Body by Science: A Research Based Program to Get the Results You Want in 12 Minutes a Week?

If you want straight up time efficiency do an HIT protocol. One intense set done to failure will give you most of the gains of a 5×5 but with much time saved. Mike Metzger and Dorian Yates used this method. Body By Science goes into the details on why it works and sample routines. An HIT routine will require less time than you have allocated.