Training and Muscle Fiber Composition

[martinelli]

Hey, guys. I have a question about the influence of one's muscle fiber composition on his or her tendency to hypertrophy from a purely aesthetic standpoint (I admit that I also posted this in the "Workout Programs" section, but I would like to maximize feedback, so sorry).

In other words, this is my question: How might differing ratios of Type I (slow-twitch), Type IIA (fast-twitch and intermediate with both aerobic and glycolytic capacity), and Type IIB (fast-twitch) fibers noticeably affect a bodybuilder's physique?

I ask this question despite the fact that the research literature shows that it is the fast-twitch fibers that display the greatest likelihood of undergoing hypertrophy. It should be easy to conclude that training should be geared toward greater expression of both of the Type II fibers in order to enhance one's physique (namely, HIIT cardio, explosive concentrics, olympic lifting, and so forth).

My problem is that the literature has also found that in bodybuilders, it is the slow-twitch fibers that display the greatest degree of hypertrophy. This is due to the nature of bodybuilding training.

This flies in the face of more traditional figures in the iron game, such as Madcow2, who argue that a readjusted focus on progressively heavier weights, coupled with some minimal volume, is going to drive more hypertrophy in the long run. But anecdotal reports (including what I have observed in my friends) and assertions made by even Mark Rippetoe, who despises bodybuilding, have shown that hypertrophy-specific training (this is not a plug for Bryan Haycock's program of the same name) produces this effect of exaggerating one's visible gains to the point that it is common to believe that a bodybuilder can lift very heavy weights, when another person of comparatively less mass may actually be able to put up an equal or heavier amount of weight because his goals have been more strength-oriented.

Regarding the previous paragraph, the pendulum seems to be swinging back and forth between these two camps. Many argue that someone who lifts heavy and eats enough is going to have a lot of muscle mass regardless. But others argue that this muscle mass will not be accentuated unless another factor is thrown into the mix: the type of training done (high sets, high reps, and minimal volume). For the longest time, I adhered to the heavy camp, but I don't have the mass to show for my strength, and I have been eating enough (trust me, I love food) and putting in my "minimal training volume." So, this has caused me to reassess what other people have said, and I am now contemplating a more mass-oriented program (and a lot of people argue that there is no such thing).

So, with this background established, I will restate my question in another way: would having more slow-twitch fibers help me if I were to undergo bodybuilding-style training?

Here is the logical progression I am familiar with:

1.) HIIT cardio and ballistic training cause the intermediate Type IIA muscle fibers to more closely mimic the mechanisms of the Type IIB glycolytic/anaerobic muscle fibers.
2.) Because these Type II muscle fibers have the greatest chance of hypertrophying, you have increased your chances of augmenting your physique that much more.
3.) HIIT cardio also has the propensity to acutely elevate your growth hormone (GH) levels depending on the degree of intensity. This should theoretically impact what type of mass you put on (assuming a hypercaloric environment). However, the point of dispute is that acute elevation in any hormone is not a very strong determinant of future anticipated outcomes. If this were true, then products such as 6-OXO, which increases the number of free, unbound testosterone in the body, would yield consistent results as far as greater mass and lower fat, but this is not widely observed. Also, it should be noted that training acutely depresses testosterone and elevates cortisol (namely, a lower T/C ratio in the body), which might suggest that we should not train, but we know that this is not the case. As a final example, pre-exercise ingestion of protein has been shown to increase insulin sensitivity, but has been simultaneously observed to acutely lower GH. But so what? Trainees who follow this practice still look good.

However, here is the other side of this topic: bodybuilding induces the opposite effect upon the Type IIA intermediate fibers, so that they more closely mimic the mechanisms of the aerobic, Type I fibers. Despite this, bodybuilders display superior hypertrophy (the majority of which is surprisingly attributed not to the fast-twitch fibers, but rather the slow-twitch). The implication is that the percentage of Type IIB and possibly Type IIA fibers has no bearing on the degree of hypertrophy a bodybuilder may experience, because they were never the chief factor in achieving this type of hypertrophy to begin with.

The conclusions we can draw from this statement are that HIIT cardio can be tossed out the window, a minimum amount of strength work should be done (just enough to retain baseline strength), and high-volume work should be emphasized.

I will not disagree that for any given level of strength, the high-volume work done will progressively elicit more pronounced hypertrophy.

Namely, if we were to compare two individuals with identical genotypes and environmental factors (stress, lifestyle and eating habits, rest, and training styles), it should be observed that:

1.) If Person A has a bench max of 300,
2.) and Person B has a bench max of 225,
3.) then the volume work that Person B performs should predictably net more hypertrophy due to his higher level of strength, which should positively affect his volume threshold (strength training has indeed been shown to have carryover to more endurance-oriented training - bodybuilding!)

This is a topic that Alan Aragon states has some merit. Myofibrillar hypertrophy (the more functional, long-term hypertrophy) "pushes up the ceiling for growth" caused by sarcoplasmic hypertrophy (the more transient, volume-induced hypertrophy).

My question is nothing new and restates what has been said for years. My question is, "Can explosive training and cardio be ignored in favor of higher-volume work for the purposes of maximal hypertrophy?"

[martinelli]

Anyone?

[s2814fun]

I think you'd get more responses, but your initial post is a little daunting to look at. Basically your asking if you can replace explosive training and cardio for High volume training. So theres the question guys....

[sincerelyryan]

I'm not going to get into a lot of the mumbo jumbo you talked about, because it is over my head.

What I do know is that all beginners have little to no control over their muscles and have a piss poor mind-muscle connection. Give them a weight and say "the amount you use doesn't matter, make it work the muscles the way you want and to the extent you want" and you'll get a blank stare after they've just swung up 20 reps that didn't do anything for them (There are many posts each day about people's inability to "feel" exercises).

Due to this, IMO, lifting for strength and numbers is a good foundation for beginners since it is tangible progression. Along the way they will learn to make the weights work for them, and after that point they can focus more on a bodybuilder style workout.

[masterjb]

I would say as in most things bbing, a combonation is what works best. Do explsive heavy low volume workouts sometimes plus cardio, and do high volume lower weight other times. That is what I do and I get pretty good results. So go heavy low volume for 4 weeks, then high volume maybe 6 weeks. Periodization is what most seem to miss in these debates.

[Zoofus]

Originally Posted by martinelli

This flies in the face of more traditional figures in the iron game, such as Madcow2, who argue that a readjusted focus on progressively heavier weights, coupled with some minimal volume, is going to drive more hypertrophy in the long run.

Having read a lot of that stuff your comment about progressively heavier weights over time is accurate but "some minimal volume" is false. I haven't read a single piece on that site or any other to support the "minimal volume". What I have found is volume specific for the individual at a point in time and the goal with a whole lot about increasing volume/workload and altering programing from linear progress to more traditional periodization as time progresses. I would guess the entire idea behind the intermediate program is setting volume very low to provide a good starting point "for the masses", note the advanced program which is explicitly contrasted with it on a workload basis has much higher volume and there are several ideas about increasing it further as someone requires more.

Also there's a number of pieces on that site about planning training over time where one might move from strength focused in parts of the year to more hypertrophy focused and even utilize a 3-4 day split for specialization in hypertrophy. That would seem to address your ultimate question in that it's not a matter of ignoring helpful aspects and concentrating on one thing but prioritizing them and phasing them optimally over a longer term plan. There's a good discussion of this in Ripp's Practical Programming too.

I wouldn't draw too many conclusions from the 2nd and 3rd hand internet posts and theories out there. Go to the source.