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Inroad vs Effort

I’ve read about studies that demonstrate similar gains in muscular size & strength between groups using lighter weights with higher repetitions and groups using heavier weights and lower reps when sets are taken to failure. If inroad were the determining factor, would we not expect the lighter weight group to have experienced greater gains, since they would have achieved a higher level of inroad? Is there something else in play, or am I misunderstanding inroad as Dr. Darden is using it in the new 30-10-30 book?

Like this study?
(and note, it’s all 4 sets, what they mean by ‘high volume’ is 4 sets of 30 is way more reps (volume) than 4 sets of 8.

however, MYO remained elevated (199%) above rest at 24 h only in 30FAIL.


These results suggest that low-load high volume resistance exercise is more effective in inducing acute muscle anabolism than high-load low volume or work matched resistance exercise modes.

It would be interesting to see a study with a selected standardized group of natural trainees, comparing HVT with extreme HIT 30-10-30.

As much as I wish I understood any of that, it’s out of my wheelhouse. What’s the findings? My question has more to do with lighter loads to failure vs heavy loads to failure & similar increases in size & strength & not really about volume. The fact that size & strength increases are similar for light loads as they are for heavy loads when effort is equal seemingly contradicts the viewpoint that inroad is more important than effort.

the findings were that lighter loads had almost double the growth response of heavier loads at the same volume. So that study anyway, would confirm that deeper inroad is more stimulating

Gotcha. Thanks.

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Even after bugging people to death on this forum for a while now on some of these same things I’m still in the same boat that you are about not understanding this inroad stuff and how it works but it does seem to! My 30 10 30 workouts are not near as brutal as how I worked out before with 2 sets of 10 or so to failure but I’m making progress weight and reps wise much faster than I did the old way, at least for the time being.

But they didn’t measure hypertrophy, they measured muscle protein synthesis, which isn’t always a proxy for hypertrophy.

One way to explain the result: low load high volume > more reps > more muscle damage > more protein synthesis to deal with the greater level of damage.

Now if damage were for sure the trigger for hypertrophy, then you make the case. But I don’t think that is the case. Maybe protein synthesis is increased just enough to compensate for the extra damage, but no additional muscle tissue is added?

It has been known for awhile that eccentric resistance training stimulates more muscle protein synthesis than concentric training. At one point that was thought to be proof that eccentric contractions produced more hypertrophy. But some more recent studies have found that the increased MPS is almost entirely driven by the extra damage done to the muscle, and doesn’t necessarily produce any more super compensation.

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Inroad is just fatigue, the momentary weakening of a muscle as it works. The decline in force output is due to a lot of stuff: depletion of local stores of ATP, phosphocreatine and glucose, accumulation of metabolic byproducts, local and central neurological fatigue, and probably other stuff that I don’t understand very well, like Calcium ion leakage into the muscle fibers.

Momentary Muscular Failure is really just Task Failure: As you perform an exercise with a fixed amount of resistance, the working muscles fatigue and produce less force. At some point, the force output from the muscle drops below the resistance provided by the weight or the machine, and movement stops. Depending on the nature of the exercise, the failure may occur at roughly the same point, and that is often then labeled as a “sticking point” for the exercise. But if the machine has a resistance curve that is well matched to the muscle, the location for failure may seem or feel a little more random.

Not all methods of resistance training lead to momentary muscle failure: If you are working against a motorized resistance, or straining against a stationary object (overcoming isometrics) then your muscle keeps weakening and weakening until the discomfort becomes too great to take, and you just give up. Drop sets accomplish the same thing albeit with breaks to allow the weight to be changed.

My point is that there are a variety of ways to inroad deeply without necessarily hitting failure. Dr Darden believes his 30-10-30 provides another way.

What seems to be unique about hitting failure is that the nervous system really ramps up and starts hammering on those poor tired muscles, firing nerve impulses again and again, with a growing degree of futility. That is stressful to the nervous system, and that can take some extra time to recover from.


Al- True… but… we know more PS is at least a possible indicator of increased hypertrophy. If you read the study you see a lot more was also of the sarcoplasmic fraction which isn’t related to damage.

Yes, if RBE hasn’t occurred, then PS is higher due to damage. Same with ecc training, the first couple workouts the PS is much higher and the ‘extra’ is for repair not growth.
I myself though highly doubt damage would be higher with a 30RM over an 8RM…

The question is whether inroad should be the objective. If it were the trigger for hypertrophy we should expect subjects using lighter weight with higher reps to have significantly more gains in size & strength than subjects using heavier weight and fewer reps, since they would have achieved deeper inroad. But the studies indicate no significant difference in strength & size gains when effort is the same. That seems to suggest that effort, whether to failure or not, is more a factor in stimulating hypertrophy than inroad.

Al- Yes agree on that, but ‘inroad’ as it’s coined is momentary force loss, it, I’m sure, isn’t a trigger but what causes that force loss may be highly related to the stimulation. If we think about what hypertrophy is ‘for’… it’s to make up for a loss of force during a fatiguing task. For survival.
If a task causes so much weakness that the suvival might be threatened, an increase in the number of fibrils would lower that risk if that same task were repeated.

gatorcpa- that study I posted was showing exactly that, that the lower load (which would be a deeper inroad) does increase the growth stimulus a lot. Also, newer studies on trained people show going to failure increases hypertrophy more than not going to failure (deeper inroad).
(see Brad Shoenfeld’s latest meta on this very thing)

There is also an interesting Russian theory on the energetic theory for muscle hypertrophy. I even wrote an article on that years ago. It states the depth of ATP loss, which surpresses mTOR, is the sitmulus as mTOR rebounds much higher and in proportion to that depth, afterwards.

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NWlifter and Average Al, this stuff is great , I just wish I understood you better. Most of it flys over my head !

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== Scott ==
So does this study suggest that higher reps of 30 have more potential for hypertrophy than lower reps of 8 of the same volume ?

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That’s basically my belief at the moment: inroad is an inevitable side of effect of doing whatever you need to do to trigger growth. Since inroad is basically fatigue, and muscles inevitably fatigue when you force them to work hard by any training method, inroad will always have some association with training adaptations. But correlation doesn’t always mean causation.

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If deep inroad were the key, then extended drop sets would be the ultimate training method. Go close to failure, reduce the weight, go close to failure, reduce the weight again, go close to failure again. Rinse and repeat until you can barely move. And what you’ll likely get is not gains, but hospitalized for rhabdomyolysis.

== Scott==
How do we define effort vrs inroad ? How do we know when the effort we put forth from two different methods is the same like lower reps vrs higher reps ?

Scott, yes that is what ‘that’ study actually measured in those subjects, almost double the stimulation. Same volume, 4 sets, but high reps instead of lower reps.

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