Dear navigator,
The first or last rep, which is the most productive? Or perhaps, the reps between the alpha and omega? We shall take productive here to mean "efficient for causation of muscle growth".
HIT advocates argue that the last rep must be the most productive because one is at their momentary weakest and thus, most growth is stimulated when blasting through that last rep because it is at that weakest moment that inroads are made into reserves, etc. We do know that training to failure may work half well for strength gains but not so good for any growth, if at all. And in the long-term, training to failure is a slow, painful plateau of non-growth, joint/soft-tissue strain and the need for ever increasing amounts of weight just to reach failure but for what....? Would this be efficient for causation of muscle growth? No. Not when research has shown that size can precede strength and should precede strength if hypertrophic specificity is the end one wishes to seek. Muscle eventually becomes resistant to growth stimulus, whatever increase in strength is largely neural, without any concomitant increase in size. Why lift humongous amounts of weights only for little growth? It is more efficient to lift lesser amounts of weights for the same or more growth. This is the dilemma of HIT. Strategic Deconditioning will re-sensitize the muscles to growth stimulus.
For those who argue the first rep is the most productive, again, we ask, productive in what context? Weightlifters, powerlifters and all such strength athletes are concerned with demonstration of strength. To date, there is no contest where they have to rep it out to get a medal. Theirs is but a question of rep maxes, and the person with the biggest lift (in single or by aggregate of different lifts) is the winner. And thus, they train for their event in such fashion - Max singles, multiple sets and long rest periods between sets. For them, it's the first rep that counts because each attempt (usually, competitions allows for 3 attempts per lift) allows for only one rep. Would such style of lifting be efficient for causation of muscle growth? No. Indeed, these guys do get big and strong as a consequence of their lifting, not so much due to their wanting to get big and strong. Their style of training is aimed at honing skill in lifting the most weight at one go. Furthermore, weightlifters build skill in lifting the weight in an efficient line of thrust, locking out at the joints, wearing lifting shirts and all such means of reducing mechanical load on muscles while hoisting large amounts of weight - all this is aimed at lifting more weight for less effort i.e. efficiency in lifting weights. It is not in any way efficient for causation of muscle growth.
The principles of HST are well elucidated in the FAQ and elsewhere on the HST site. It is not training to failure that promotes growth. It is not the first rep that elicits growth. In HST, there is no focus on any particular rep but instead, each and every rep has purpose and value as a means of eliciting mechanical stress, metabolite build-up etc. Thus, in HST, every rep counts and one would be prudent in making sure all reps are executed in good form.
To end, there is truth in saying that the in-between reps are beneficial. Without the first rep there cannot be the last, and without the last rep there cannot be the in-betweens. It is the harmonization of HST principles put forward so succinctly, eloquently yet scientifically that makes Bryan's brain-child a worthwhile piece of science, but more so, a work of art.
Godspeed, and happy HSTing
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