Are you a Newbie? Yeah...I didn’t think so.

If you’ve found your way to elitefts™, I doubt that you’re a complete “newbie” to the Iron Game. Poking through the research studies I cited in Part 1 of this series on peri-workout recovery supplementation (RS), you probably noticed that experiments with highly-trained subjects are few and far between. This may seem like an obvious limitation in applicability since you aren't a newbie research subject (and vice versa), but I sometimes like to break things down a bit more. Don’t get me wrong here—physiological phenomena, responses, and adaptations to training and nutritional interventions will definitely show tremendous similarities between beginners and gym vets; however, there are differences. In this article, I’d like to clarify this further, even if that means turning science on itself just a tad. So, below are a few (and perhaps potentially surprising) training-related dissimilarities to keep in mind when sizing up peri-workout RS studies, as well as exercise studies in general.

Once…Twice…Two Times a Bad-Ass

It only takes a single bout of damaging and soreness-producing exercise, especially those involving eccentric (lengthening) contractions, to produce a dramatic “protective effect.”  The next time you repeat that same bout, the exercised muscle is “protected” against muscle soreness and damage (1)—an effect that may last as long as six months (2). This is important because damaging eccentric exercise impairs insulin action and fuel breakdown in skeletal muscle (3-5). This means that the effects of a given peri-workout RS might very well differ when comparing a first (novel) vs. a second (protected) bout. Even isometric exercises and very low load (20% max effort) eccentric contractions—the types of activities used to estimate strength or familiarize subjects, can confer a protective effect (6) and cause test/re-test issues. From what I've seen, it’s pretty rare to find a study employing a half year “washout period” between exercise tests. Amongst the thousands of studies employing pre-testing and/or repeated tests of untrained and un-acclimated subjects, I’d bet a few have suffered from this order-related confounding effect.

Using randomized, blinded, and counterbalanced testing conditions can do the trick here. (In other words, mixing up the order of the placebo vs. the tested RS so that no one knows who’s getting what). Unfortunately, researchers don’t always double check that this strategy actually worked to minimize and order effect. (This is done by using statistics to analyze testing order as a “covariate”). Another decent solution to this conundrum is to use subjects as their own “internal control." For example, this would be like exercising just one leg under different conditions, therefore showing protein RS vs. carbohydrate-loaded RS (7). This, however, leaves us with an external validity issue. For instance, who goes to the gym to train only one leg?  (See Part 1  for more on external validity.) Beyond that, the repeated-bout protective effect may (8, 9) be partly “central” in nature, meaning that there is a learning effect in the brain. Exercising one leg may actually protect the other leg from damage even if the subject has never actually performed a rep with that leg (8, 9)—perhaps it is a practice phenomenon or cross-training effect (10) .

Untrained Muscle Confusion?

You might say that untrained muscle hasn't “found its way” in the training realm, or perhaps it is just a bit overprotective and under-specialized. As expected, a first-time resistance exercise bout turns on myofibrillar protein synthesis—the beginning of growing a larger muscle. However, to muscle that is naïve to resistance exercise, the harsh reality of hitting the weights for the first time is also enough of an insult to increase mitochondrial (for aerobic energy production) protein synthesis. Over the long haul, resistance training fine tunes the muscle’s responsiveness. Therefore, mitochondrial content or density is not typically increased (11-13), and a single bout of resistance exercise does not increase mitochondrial protein synthesis (14).

Unfortunately, simply studying “generically” resistance-trained subjects may not fully control for this “novelty” effect. In other words, even if someone has been pounding the iron for years, lab resistance training may be different from what he or she does in his or her home gym. At the far ends of the training spectrum, if we compare an endurance-trained muscle response to a resistance exercise bout to its counterpart (a “platehead’s” muscle responds to an endurance bout), the molecular machinery (signaling the molecules directing adaptation) put into motion in both cases actually overlap considerably. On the other hand, endurance-trained and resistance-trained muscles show specialized responses to their habitual modes of exercise (15). This suggests that there is some generalized response when exercising in a way to which you’re not accustomed (16). On the flip side, though, these examples tell us how the principle of specificity of training manifests right down to the molecular level.

The underpinnings of these phenomena and how long it may take for the response to “match” the adaptation is poorly understood (17). Thus, even in studying “resistance-trained” subjects, the novelty of the experimental workout (just like training with a new partner, using different training parameters, and using different equipment, etc.) can mean a different response in the lab vs. when those same subjects go through their regular workouts.

No Study is Perfect

Don’t get me wrong, I've performed studies with many weeks of familiarization (18), and I have also trained subjects employing an internal control strategy (unilateral leg training) (19). Therefore, I know that research isn't easy and no study is “perfect.”  So, I won’t put you to sleep with a full-blown literature review, but in the context of training studies of peri-workout RS and what I've explored in this article and its predecessor here are some interesting factoids:

  • Two studies showed no benefit of an RS employed with either unilateral (one-legged) training (20) or a small muscle mass like elbow flexors (21), but when an almost identical supplement (20 grams of protein pre- and post-exercise) was given over the course of a full body training program, muscle growth was enhanced (22).
  • Two training studies in the elderly, who seem to need more protein than younger folks (23), found that a paltry (24) 10 grams of protein pre- and post-exercise is ineffective (25). In turn, postponing protein intake after exercise by two hours devastates strength gains and eliminates muscle growth (26).
  • One difficulty in testing highly-trained subjects is that body composition and performance changes are small. For instance, a training period would ideally elicit some changes if one were able to detect enhancement of gains. A training study featuring college football players suffered from this pitfall, where no subjects, regardless of RS or timing, improved body composition (27). This study also employed a volunteer control group that received no RS—placebo or real, which, as you can imagine among teammates training together, might have had a psychological and thus physiological impact (28).
  • Even training studies with trained subjects showing benefits of peri-workout RS have excluded subjects “who had consumed any nutritional supplements three months prior to the study (29).” This probably means that many of you who are reading this would not have made the cut. (The implied question is whether this study applies to you or only to those who have abstained from nutritional supplementation for at least three months...)
  • A well-done study supporting peri-workout RS timing (30) familiarized subjects (recreationally-trained bodybuilders to boot) for about 10 weeks in order to limit the “novelty effect” I mentioned above, as well as to minimize the neural effects on strength gains that manifest early on in a new program (31). The control group took the same “recovery supplement”—but in the morning and evening rather than before and after exercise. The RS actually included creatine in addition to carbs and protein, so teasing out macronutrient vs. creatine timing effects was off the table. On the other hand, who doesn't or hasn't taken creatine if they consume supplements beyond a simple multivitamin?

BOTTOM LINE: Training status and age matters—from the rate of gains to the basic ways in which a muscle rallies its resources to adapt to a novel exercise stress. Not only is this is good to keep in mind when a new study comes your way, but it is also a good reference when framing the kinds of improvements you might expect in a seasoned bodybuilder or athlete who is trying to build on years of hard-earned gains.

In Part 3 of this article series I’ll integrate my take on the research literature with personal and client experiences, and I'll hit you with some of my best tips on making peri-workout recovery supplementation work for you.

References

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  2. Nosaka, K., et al., How long does the protective effect on eccentric exercise-induced muscle damage last? Med Sci Sports Exerc, 2001. 33(9): p. 1490-5.
  3. Asp, S., et al., Eccentric exercise decreases maximal insulin action in humans: muscle and systemic effects. The Journal of physiology, 1996. 494 ( Pt 3): p. 891-8. http://www.ncbi.nlm.nih.gov/pubmed/8865083
  4. Asp, S., et al., Exercise metabolism in human skeletal muscle exposed to prior eccentric exercise. J Physiol (Lond), 1998. 509(Pt 1): p. 305-13. http://www.ncbi.nlm.nih.gov/cgi-bin/Entrez/referer?http://www.journals.cup.org/owa_dba/owa/approval%3fsjid=PHY&said=7562&spii=S002237519807562X
  5. Asp, S., et al., Eccentric exercise decreases glucose transporter GLUT4 protein in human skeletal muscle. The Journal of physiology, 1995. 482 ( Pt 3): p. 705-12. http://www.ncbi.nlm.nih.gov/pubmed/7738859
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  7. Staples, A.W., et al., Carbohydrate does not augment exercise-induced protein accretion versus protein alone. Med Sci Sports Exerc, 2011. 43(7): p. 1154-61.
  8. Starbuck, C. and R.G. Eston, Exercise-induced muscle damage and the repeated bout effect: evidence for cross transfer. Eur J Appl Physiol, 2012. 112(3): p. 1005-13.
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  10. Weir, J.P., et al., The effect of unilateral eccentric weight training and detraining on joint angle specificity, cross-training, and the bilateral deficit. J Orthop Sports Phys Ther, 1995. 22(5): p. 207-15.
  11. Luthi, J.M., et al., Structural changes in skeletal muscle tissue with heavy-resistance exercise. Int J Sports Med, 1986. 7(3): p. 123-7.
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  17. Atherton, P.J. and K. Smith, Muscle protein synthesis in response to nutrition and exercise. The Journal of Physiology, 2012. 590(5): p. 1049-1057. http://jp.physoc.org/content/590/5/1049.abstract
  18. Stevenson, S.W. and R.P. Farrar, Simulated Rowing and Three Ergogenic Aids: Predictors and Potentiators of Performance of Simulated Firefighting (Unpublished Thesis). 1996, University of Texas at Austin. p. 232.
  19. Stevenson, S.W. and G.A. Dudley, Dietary creatine supplementation and muscular adaptation to resistive overload. Medicine and science in sports and exercise, 2001. 33(8): p. 1304-10. http://www.ncbi.nlm.nih.gov/pubmed/11474331
  20. Williams, A.G., et al., Is glucose/amino acid supplementation after exercise an aid to strength training? British Journal of Sports Medicine, 2001. 35(2): p. 109-113. http://bjsm.bmj.com/content/35/2/109.abstract
  21. Erskine, R.M., et al., Whey protein does not enhance the adaptations to elbow flexor resistance training. Med Sci Sports Exerc., 2012. 44(9): p. 1791 - 800.
  22. Hulmi, J.J., et al., Acute and long-term effects of resistance exercise with or without protein ingestion on muscle hypertrophy and gene expression. Amino Acids, 2009. 37(2): p. 297-308. http://www.ncbi.nlm.nih.gov/pubmed/18661258
  23. Yang, Y., et al., Resistance exercise enhances myofibrillar protein synthesis with graded intakes of whey protein in older men. Br J Nutr, 2012. 108(10): p. 1780 - 8.
  24. Moore, D.R., et al., Ingested protein dose response of muscle and albumin protein synthesis after resistance exercise in young men. The American journal of clinical nutrition, 2009. 89(1): p. 161-8. http://www.ncbi.nlm.nih.gov/pubmed/19056590
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  28. Pollo, A., et al., Placebo mechanisms across different conditions: from the clinical setting to physical performance. Philos Trans R Soc Lond B Biol Sci, 2011. 366(1572): p. 1790-8.
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