Volume is a key driver of muscle hypertrophy. More reps lead to more volume, but not all reps are created equal. In this article, we will know that the closer a rep is to failure, the more effective it is at building muscle. Some studies have shown that lifters who perform more effective reps build more muscle, even when similar volumes are used. Effective reps also seem more efficient, reducing workout time by about half. Mechanistically, effective reps build more muscle because they increase metabolic stress. Rest- pause or drop sets can be used to maximize effective reps, but lifters new to using them should monitor their progress carefully to avoid overtraining.
Are all reps created equal?
Some studies have shown that volume is a key driver of muscle growth. Reps increase volume. Are all reps created equal? No, that they are not, and that reps closer to failure are more effective at building muscle.
Take the following example:
Workout A: 1 set of 5 reps @ 85% 1RM (to failure)
Workout B: 5 sets of 1 rep @ 85% 1RM (far from failure)
For both workouts, a total of 5 reps @ 85% 1RM are performed. So, the volume is exactly the same. Would both workouts cause identical muscle hypertrophy? No, that they would not, because the reps of workout A are taken closer to failure than the reps of workout B. To be exact, 4 of the 5 reps are more effective at building muscle, because they are performed closer and closer to failure. The closer a rep is to failure, the more effective it is at building muscle, and that “effective reps” are reps closer to failure.
So what exactly are effective reps?
(1) Failure is “the point during a set when muscles can no longer produce the necessary force to concentrically lift a given load” (Schoenfeld, 2010).
(2) Effective reps are reps closer to failure.
(3) The closer a rep is to failure, the more effective it is at building muscle.
Evidence for the theory of effective reps
In a study, two groups of lifters did the same training protocol (3- 5 sets @ 10RM). There was just one difference between groups: lifters in group 2 rested for 30 seconds at the midpoint of each set. So, volume was equal between groups, but more “effective reps” were performed by lifters in group 1. As the theory of effective reps would predict, lifters in group 1 gained significantly more muscle cross-sectional area than lifters in group 2.
Research by Gieβsing et al. (2016) also supports this theory. In that study, lifters who trained to failure gained more lean mass than lifters who did not. Volume was similar between groups.
How might we explain that reps closer to failure are more effective?
The most likely mechanism is metabolic stress. Reps closer to failure increase metabolic stress in two ways. First, they produce more metabolites of anaerobic glycolysis, “which theoretically augments post-exercise anabolism” (Schoenfeld, 2016). Second, they restrict blood flow longer. This leads to “greater acute hypoxia in the working muscles, which may further contribute to hypertrophic adaptations” (Schoenfeld, 2016).
What’s the best way to apply the theory of effective reps?
1. First, get familiar with rest-pause or drop sets. I prefer rest-pause sets because I find they’re more convenient (no need to change the weight you lift during your set). Try them out during an experimental session.
2. Next, choose one exercise you’re familiar with, and that you can execute to failure repeatedly safely. A machine chest press might be a good option.
3. Next, replace 3 normal sets by 1 rest-pause or drop set for that exercise.
a. For drop sets, I would recommend decreasing your load by 20% 3 times.
b. Based on my own experience, for rest-pause sets, I would recommend doing reps to failure, resting for 40 seconds, doing more reps to failure, resting for 40 more seconds, and doing yet again more reps to failure. In other words, use two 40-second rests. I’ve found 40 seconds works better than the 10-20 seconds used in the literature for intermediates and advanced lifters who handle heavier weights (resting for 20 seconds did not allow us to perform more than 1-2 extra reps).
4. Carefully monitor your progress. Are you making gains using rest-pause or drop sets? Better or worse gains than when you did normal sets? Also, are you saving time? The theory predicts that you should make similar or better gains with less workout time. If that turns out to be true, you may want to use rest-pause or drop sets more and more.
5. Continue monitoring your progress as you slowly transition to using rest-pause or drop sets on more (or even all) of your exercises. Watch for overtraining, and make sure you continue making similar or better gains across the board.
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