Review 3 – Are We Acknowledging Adaptive Variability Enough?

Today we gonna look at this intervention study comparing different RT methods and their effects on muscle hypertrophy and the associated within and between-subject variability – or in other words how each participant responded to different RT protocols. It is well supported in the literature that it likely doesn’t matter what you do in the gym as long as you go until or close to muscular failure if you wanna get big. Therefore, it’s much rather the inherent intrinsic predisposition to respond to such stimuli that drive the desired adaptation. With that, however, comes an inevitable huge between-subject variability. This leads to the question of how important is the WHAT we do in the gym after all?

Adaptive Variability

Despite the EXP leg shifted way more load (the total training volume in kg) than the CON leg for almost every participant. But when we look at the change in CSA of the vastus lateralis – no difference at all on a group level, and even less than 2% difference within participants between legs. So again, no need to overcomplicate things if muscle size is the goal. Another, even more, fascinating finding, was that the between-subject variability was over 40x higher than the intrasubject variability. Or in other words, both legs adapted fairly similar, independent of what you do, but the results vastly differed to another person, despite the same RT protocol.

Individual Predisposition

Although every textbook or even certain popular RT methods out there are attaching adaptive certainties to different methods, as in doing method X and you’ll get outcome Y, this can’t be true. That’s not how complex systems behave. When we picture the spread of the probability density, we know that everything in biology is fairly normally distributed. So, I argue that better athletes, however you define better, are likely just more responsive to training, and most of them will get better despite our best intentions. I mean, without such a predisposition, even the “best” training won’t turn McLovin into a pro athlete. So, we are fighting an uphill battle there. But on the flip side, we’ve all seen pro athletes succeeding on the highest level DESPITE the training they are doing.

So, my takeaway from this is that maybe we are way too confident in our assumptions about the adaptive outcome as a result of specific training methods. How much time do we then need to invest in designing fancy periodization approaches in excel? Are we really making any difference compared to a simple RHT approach? Really hard training. What do you think?