Proliferation and Differentiation – Enough Said



New Book Release – You gotta get this one!!!!

New Book Release – You gotta get this one!!!!.

To Crunch or not to Crunch seems to be a Viable Issue in Strength and Conditioning.

HOWEVER, it is not the most heated argument. The argument could be rephrased as to what the abdominal muscles of humans are actually composed of, particularly fiber type composition. Then I would agree that this is a very heated debate.
It is time for some logic to come into this discussion. What sense does it make for posterior chain muscles to be comprised of predominately type IIa/x fibers while the anterior muscles hold higher percentages of type I fibers? The answer to the big gorilla is the whole premise is complete horsecrap and instead of using the Gorilla as an example maybe Capuchin monkey would have been a better choice. As a mammal closely related to our evolutionary ancestor, it is interesting that the study found a predominance of fast twitch fibers (FG + FOG) over slow twitch (SO) fibers (Simionato, et al., 2006). The abdominal fiber types across primates and humans are very similar in composition (Engel & Franzini-Armstrong, 2004; Simionato, et al., 2006). Man and Colleagues (2005) demonstrated that, “ the abdominal muscles have a similar fibre type distribution to the quadriceps, comprising of 46% type I fibres and 54% type II fibres” (p.721). Schiaffino and Reggiani (2011) note that in rats the, the diaphragm is made of mostly type IIx fibers, and increased resting calcium concentration produces a fast-to-slow twitch transformation, which is possible in other mammals such as humans. Further, they have demonstrated that mitochondrial calcium; in mammal skeletal muscles sequester calcium during contraction and expeditiously release it during relaxation (Schiafffino & Reggiani, 2011). This has application later in this discussion. One experiment using 599 biopsies from six human cadavers showed that the fiber makeup of humans was similar with muscles that have multiple connection points resulted in the highest amounts of fast MHC isoforms and that titin size variability can potentially act to adjust the protein’s mechanotransduction capability (Tirrell, et al., 2012). Simply put, this means that the abdominal muscles have a high capability for fiber shifts from type I to intermediate type II isoforms. Activation was significantly increased with peak EMG activity for the rectus abdominus when the muscle is pre-stretched or hyperextended (Konrad, Schmitz, & Denner, 2001). Several researchers have corroborated the fact that the abdominals are not predominantly composed of just type I fibers (Engel & Franzini-Armstrong, 2004; McComas, 1996). In one study by Haggamark and Thorstennson (1979) muscle fibers were biopsied from the four the rectus abdominus, RA, obliquus externus, OE, obliquus internus OI, and the transverse abdominus, TR in (13 subjects ages 24-55). The researchers found great inter-individual differences in fiber composition, but the differences between muscle were almost non-existent (Haggmark & Thorstensson, 1979). They discovered a mean fiber distribution of 55-58% type I, 15-23% type IIa, 21-28% type IIx, and 0-1% type IIc fibers (Haggmark & Thorstensson, 1979). That equates to 37% fast twitch muscle fibers with the capacity for fiber shifting. Practically, this means that the abdominals can be trained just like any other muscle group to include strength, muscular growth, and endurance. High repetition training for larger abdominal muscles is not justified by research.

We talk about evidence based research but include references to dead pigs and the vertebral breakdown after numerous flexion and extension cycles. Ridiculous! Dead pigs cannot regenerate the proteoglycans needed by mechanical loading, fluid shear, or genetic stimulation (Engel & Franzini-Armstrong, 2004). So why even include this garbage? Schiaffino and Reggiani (2011) demonstrate that interspecies comparison of humans and porcine fibers indicates significant interspecies diversity. This makes the mention of dead porcine stress cycles a moot point.

I had the privilege to work in the Strength Training for Arthritis study with 55plus clients with clinically diagnosed knee osteoarthritis (Messier, et al., 2013). Guess what? Well over 50% responded to strength training of the knees and came off pain medication. Remember when we were told without question that squats kill the knees? Now it has become a treatment modality. The same applies for spinal flexion and extension. It is not wise to speculate there is a life cycle for vertebra in normal humans, because the evidence is not there and practical application in the gym proves otherwise.

Real World
In the real world each person has varying types of fiber composition in their abdominals, but the numbers do not vary that much. That gorilla can have a very strong rectus abdominus with the right training methods. Abdominals, just as any other major trained muscle group can grow through specifics mechanisms I will address in future articles.

If you want big abdominals train in the hypertrophy/hyperplasia range. If you want strong abdominals progressively load the weight using the right Periodization. If you want muscular endurance seen in the athletes performing thousands of abdominal exercises per day, then Periodize muscular endurance. This is an often overlooked that was mentioned previously as a role if fiber type transition occurs. It is not that all of these athletes have slow SOG fibers in the abdominals, but as the result of continuous repetitive endurance effort, a heavy myosin transition occurs. This transition from type IIx to intermediate forms suited for endurance training is beneficial for these types of athletes. Interestingly, if these athletes were followed and biopsies taken before and after training cessation, I would bet a thousand bucks a fiber transition occurred and returned to normal. Remember the principle of specific adaptation to imposed demands (SAID)? This is integral abdominal training.

What is the evidence based research for planks? What about crunches where the lumbar region is not fixed? What about sit-ups without lumbar support as well? Are we training hip flexors or abdominals?
The best way to train the abdominals is to support the lumbar region. Various machines accommodate the third curvature of the spine. These exercises should be performed without the lower back flattening out and the pelvis tilting. We need to move away from fads and do what works. The majority of the exercises recommended by current experts are not worth their weight in fly splatter.

Evidence supports a higher composition of type IIa and type IIx in the abdominal muscles than previously thought. Food for thought: If you see type IIb mentioned in a study it is bullcrap – it does not exist in humans (Engel & Franzini-Armstrong, 2004). If you want bigger abdominals progressively overload them using weights targeted at hypertrophy and hyperplasia at approximately 65-80% of the repetition maximum. If you are a strength athlete, do not be afraid to load 70-90+ % of the repetition maximum as long as you use the correct exercises and the lumbar is supported. For endurance athletes pick the target ranges and kill yourselves with that type of training. Better you than me.
So now the GIANT defecating Gorilla has been addressed. Who is next?

Engel, A. G., & Franzini-Armstrong, L. C. (2004). Myology (3rd Edition). New York, NY: McGraw-Hill Medical Publishing Division.
Haggmark, T., & Thorstensson, A. (1979). Fibre types in human abdominal muscles. Acta Physiologica Scandinavia, 107(4), 319-325.
Konrad, P., Schmitz, K., & Denner, A. (2001). Neuromuscular evaluation of trunk-training exercises. Journal of Athletic Training, 36(2), 109-118.
Man, D.-C. W., Hopkinson, N. S., Harraf, F., Kkoletou, D., Polkey, M. I., & Moxham, J. (2005). Abdominal muscle and quadriceps strength in chronic obstructive pulmonary disease (p. 721). Thorax: BMJ Open Respiratory Research, 60, 718-722.
McComas, A. J. (1996). Skeletal muscle form and function. Champaign, IL: Human Kinetics.
Messier, S. P., Mihalko, S. L., Beavers, D. P., Nicklas, B. J., DeVita, P., Carr, J. J., . . . Loeser, R. F. (2013). Strength training for arthritis trial (START): Design and rationale. BioMed Central Open Access, 14(208), 1-15.
Schiafffino, S., & Reggiani, C. (2011). Fiber types in mammalian skeletal muscles. Physiology Review, 91, 1447-1531.
Simionato, L. H., Andreo, J. C., de Oliveira, J., Bortoluci, C. H., dos Santos, N. B., Moraes, L. H., . . . Andreo, M. B. (2006). Morphology and histochemistry of the rectus abdominus muscle fibers of tufted Capuchin monkeys (Cebus apella, Linnaeus, 1758). International Journal of Morphology, 24(1), 53-60.
Tirrell, T. F., Cook, M. S., Carr, J. A., Lin, E., Ward, S. R., & Lieber, R. L. (2012). Human skeletal muscle biochemcial diversity. The Journal of Experimental Biology, 215, 2551-2559.

New Book Release – You gotta get this one!!!!

The difference between proliferation and differentiation…

Lately, there have been many comments in various forums about the actual functions of MGF-I and IGF-I. Before moving forward, some definitions are in line. First, proliferation is the mitotic division of cells into a population of identical cells, whereas differentiation occurs when the genetic program of a cell has been assigned. IGF-I is an acronym for insulin-like growth factor one that occurs in the variations of IGF-IEa, IGF-IEb, and IGF-IEc. IGF-I is secreted in the body in an autocrine and paracrine fashion. The variant isoform IGF-IEc is made in the skeletal muscles in an autocrine fashion and is referred to as mechano growth factor one or MGF-I. Paracrine IGF-I is released from the liver into systemic circulation.
During the repair of skeletal muscle, from intense resistance training, the adaptational process is characterized by activation, proliferation, and differentiation (McKay, O’Reilly, Phillips, Tarnopolsky, & Parise, 2008). Although the research remains equivocal, two views remain supported. Borer (2013) describes the proliferative phase as the resultant action of IGF-IEb and MGF variants. McKay and colleagues (2008), however, assign the temporal response of MGF, alone, in relation to the activation/proliferation phase of the overall genetic program with increases in Myf5 and MyoD. Consequently, IGF-1Ea and IGF-1Eb were viewed in temporal relation to differentiation by increased MRF4 and myogenin expression (McKay, et al., 2008).
This latestest research can be interpreted as activation and proliferation involving MGF-I produced locally in the muscle by a mechanical stimulus into a population of cells. Further, differentiation of the population into myoblasts occurs from action of IGF-IEa and IGF-IEb after acute muscle trauma.
Borer, K. T. (2013). Advanced exercise endocrinology. Champaign, IL: Human Kinetics.
McKay, B. R., O’Reilly, C. E., Phillips, S. M., Tarnopolsky, M. A., & Parise, G. (2008). Co-expresssion of IGF-1 family members with myogenic regulatory factors following acute damaging muscle-lengthening contractions in humans. The Journal of Physiology, 5549-5560.



Periodization- The “The Beginning in Bodybuilding”

Periodization- The “The Beginning in Bodybuilding”.

95% of all trainers don’t know correct exercise form leading to total failure of strength progams before they even start.

95% of Trainers do not know correct exercise form leading to total failure


“With some many videos and diagrams available on the market today how do we as bodybuilders  and sports trainers really know what is right”?

And I say that trying to give some a little credit. How do you know truth about exercise form. Or better yet what is bullshit? Hopefully after reading this article you may get some idea of  just how much misinformation if out there an how better to learn the truth.

One of the things I got involved in years ago when I was writing For Ironman Magazine under the column of Muscle Coach was using drawings to illustrate the correct form to do exercises. My teacher at the time Robert K. Blom RPT always drummed into my head as many teachers do was the importance of understanding the muscle you want to work and getting the form right from the beginning. Now of course you have…

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