|Are NSAIDs over-the-counter anabolics from the pharmacy next door?|
It is thus neither guaranteed, nor likely that a young man or woman would see the same 28% extra-increase in type I fiber and 11% extra-increase in type II fiber diameter, Trappe et al. describe in their soon-to-be-published paper in the journal of the Gerontological Society of America (Trappe. 2016).
I do understand, though that the numbers still got your attention. Well, let's take a close look at how the researchers got to these impressive results. It all started with previous research that suggested that common cyclooxygenase (COX)-inhibiting drugs enhance resistance exercise induced muscle mass and strength gains in older individuals.
Unfortunately, the results of the few studies we have, are conflicting (Schoenfeld. 2012; see Table 1) - with one showing benefits and two showing no effect at all. The purpose of Trappe's latest study was thus to (a) simply gather more evidence and (b) investigate the mechanism behind the changes that were observed in previous studies. Or, as the scientists put it "whether the underlying mechanism regulating this effect was specific to Type I or Type II muscle fibers" (Trappe. 2016).
|Table 1: Summary of human studies investigating the effect of nonsteroidal anti-inflammatory |
drug consumption on muscle hypertrophy (Schoenfeld. 2012).
"All participants completed a progressive resistance exercise training program of bilateral knee extension that was designed to hypertrophy and strengthen the m. quadriceps femoris, using a protocol employed for several previous investigations in our laboratory. Each participant was scheduled for resistance training three times per week over the 12 weeks for a total of 36 sessions on an isotonic knee extension device (Cybex Eagle, Medway, MA). All sessions were supervised by a member of the research team. Each session was separated by at least 1 day and consisted of 5 minutes of light cycling (828E, Monark Exercise AB, Vansbro, Sweden), two sets of five knee extensions at a light weight, followed by three sets of 10 repetitions with 2 minutes of rest between sets. Training intensity was based on each individual’s one repetition maximum (1RM) and adjusted during the training based on each individual’s training session per formance and biweekly 1RM" (Trappe. 2016).The compliance of the subjects of this double-blinded study is described as excellent. Therefore, we can assume that the significance of the results of the scientists' analysis of muscle samples that were examined for Type I and II fiber cross-sectional area, capillarization, and metabolic enzyme activities (glycogen phosphorylase, citrate synthase, β-hydroxyacyl-CoA-dehydrogenase) is high.
|Figure 1: Pre-/post comparison on fiber (according to fiber type) and muscle size (Trappe. 2016).|
|Schematic of the prostaglandin (PG) producing cyclooxygenase (COX) pathway and specific receptors that influence growth and atrophy in skeletal muscle (Trappe. 2013b).|
In addition, the authors point out that previous evidence suggests an "additional mechanism for the COX inhibitor–induced supplemental growth, working through PGF2α receptor and protein synthesis upregulation" (Trappe. 2016; referring to Trappe. 2013a,b).
- Mikkelsen, U. R., et al. "Local NSAID infusion inhibits satellite cell proliferation in human skeletal muscle after eccentric exercise." Journal of applied physiology 107.5 (2009): 1600-1611.
- Schoenfeld, Brad J. "The Use of Nonsteroidal anti-inflammatory drugs for exercise-induced muscle damage." Sports medicine 42.12 (2012): 1017-1028.
- Standley, R. A., et al. "Prostaglandin E 2 induces transcription of skeletal muscle mass regulators interleukin-6 and muscle RING finger-1 in humans." Prostaglandins, Leukotrienes and Essential Fatty Acids (PLEFA) 88.5 (2013): 361-364.
- Trappe, Todd A., and Sophia Z. Liu. "Effects of prostaglandins and COX-inhibiting drugs on skeletal muscle adaptations to exercise." Journal of Applied Physiology 115.6 (2013a): 909-919.
- Trappe, Todd A., et al. "Prostaglandin and myokine involvement in the cyclooxygenase-inhibiting drug enhancement of skeletal muscle adaptations to resistance exercise in older adults." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 304.3 (2013b): R198-R205.
- Trappe, Todd A., et al. "COX Inhibitor Influence on Skeletal Muscle Fiber Size and Metabolic Adaptations to Resistance Exercise in Older Adults." J Gerontol A Biol Sci Med Sci (2016): Advance Access publication January 27, 2016.
- Thornell, Lars-Eric. "Sarcopenic obesity: satellite cells in the aging muscle." Current Opinion in Clinical Nutrition & Metabolic Care 14.1 (2011): 22-27.