So I am a few months behind on research updates, but have no fear as more good stuff is coming. For June some great studies on pre and post protein and carbohydrate beverages, NSAIDs (like Advil) and their effects on muscle growth, and some molecular mechanisms in action.
Be sure to check out my previous post HERE on protein synthesis (adding muscle) and what you can do to maximize it based on bleeding edge research.
If all this crazy research makes your head spin back like a Pez dispenser and just want to get the plan and get started today, check out Jimmy Smith's Physique Formula.
Let's get to it
Differential effects of resistance and endurance exercise in the fed state on signaling molecule phosphorylation and protein synthesis in human muscle.
Wilkinson SB, Phillips SM, Atherton PJ, Patel R, Yarasheski KE, Tarnopolsky MA, Rennie MJ. McMaster University.
Resistance (RE) and endurance (EE) exercise stimulate mixed skeletal muscle protein synthesis. The phenotypes induced by RE (myofibrillar protein accretion) and EE (mitochondrial expansion) training must result from differential stimulation of myofibrillar and mitochondrial protein synthesis. We measured the synthetic rates of myofibrillar and mitochondrial proteins and the activation of signaling proteins (Akt-mTOR-p70S6K) at rest and after an acute bout of RE or EE in the untrained state and after 10 wk of RE or EE training in young healthy men. While untrained, RE stimulated both myofibrillar and mitochondrial protein synthesis, 67% and 69% (P<0.02), p=" 0.05)." style="font-weight: bold;">
Conclusion: Chronic resistance exercise (wt training) or endurance exercise training modifies the protein synthetic response of functional protein fractions, with a shift toward exercise phenotype-specific responses, without an obvious explanatory change in the phosphorylation of regulatory signaling pathway proteins.
My notes: sounds like the SAID principle in action! The body is adapting specifically to the stimulus (exercise)
Essential amino acid and carbohydrate ingestion prior to resistance exercise does not enhance post-exercise muscle protein synthesis.
Fujita S, Dreyer HC, Drummond MJ, Glynn EL, Volpi E, Rasmussen BB.University of Tokyo. Ingestion of an essential amino acid-carbohydrate (EAA+CHO) solution following resistance exercise enhances muscle protein synthesis during post-exercise recovery. It is unclear whether EAA+CHO ingestion prior to resistance exercise can improve direct measures of post-exercise muscle protein synthesis (FSR; fractional synthetic rate). We hypothesized that EAA+CHO ingestion prior to a bout of resistance exercise would prevent the exercise-induced decrease in muscle FSR and would result in an enhanced rate of muscle FSR during post-exercise recovery. We studied 22 young healthy subjects before, during, and for 2 hr following a bout of high-intensity leg resistance exercise. The Fasting control group (N=11) did not ingest nutrients and the EAA+CHO group (N=11) ingested a solution of EAA+CHO 1 hr prior to beginning the exercise bout. Stable isotopic methods were used in combination with muscle biopsies to determine FSR. Immunoblotting procedures were utilized to assess cell signaling proteins associated with the regulation of FSR. We found that muscle FSR increased in the EAA+CHO group immediately following EAA+CHO ingestion (P<0.05),>0.05). Eukaryotic elongation factor 2 phosphorylation was reduced in both groups at 2 hr post-exercise (EAA+CHO: 39+/-7%; Fasting: 47+/-9%; P<0.05). style="font-weight: bold;">
Conclusion: We conclude that essential amino acids and carbs (EAA+CHO) ingestion prior to resistance exercise does not enhance post-exercise fractional synthesis rate (FSR--Fractional Synthetic Rate--aka rate of adding protein to muscles) as compared to exercise without nutrients.
My note--while this interesting, I would not dump your protein carb drink before lifting just yet. Based on info from Dave Barr (source, AI and personal conversation) moving it to 15 minutes before training may be more ideal. Stay tuned!
Gene expression profiling in human skeletal muscle during recovery from eccentric exercise.
Mahoney DJ, Safdar A, Parise G, Melov S, Fu M, MacNeil L, Kaczor J, Payne ET, Tarnopolsky MA. Department of Medical Sciences, McMaster University Medical Center, 1200 Main Street W., Hamilton, Ontario, Canada. We used cDNA microarrays to screen for differentially expressed genes during recovery from exercise-induced muscle damage in humans. Male subjects (n = 4) performed 300 maximal eccentric contractions, and skeletal muscle biopsy samples were analyzed at 3 h and 48 h after exercise. In total, 113 genes increased 3 h postexercise, and 34 decreased. At 48 h postexercise, 59 genes increased and 29 decreased. On the basis of these data, we chose 19 gene changes and conducted secondary analyses using real-time RT-PCR from muscle biopsy samples taken from 11 additional subjects who performed an identical bout of exercise.
Real-time RT-PCR analyses confirmed that exercise-induced muscle damage led to a rapid (3 h) increase in sterol response element binding protein 2 (SREBP-2), followed by a delayed (48 h) increase in the SREBP-2 gene targets Acyl CoA:cholesterol acyltransferase (ACAT)-2 and insulin-induced gene 1 (insig-1). The expression of the IL-1 receptor, a known regulator of SREBP-2, was also elevated after exercise. Taken together, these expression changes suggest a transcriptional program for increasing cholesterol and lipid synthesis and/or modification. Additionally, damaging exercise induced the expression of protein kinase H11, capping protein Z alpha (capZalpha), and modulatory calcineurin-interacting protein 1 (MCIP1), as well as cardiac ankryin repeat protein 1 (CARP1), DNAJB2, c-myc, and junD, each of which are likely involved in skeletal muscle growth, remodeling, and stress management.
Conclusion: In summary, using DNA microarrays and RT-PCR, we have identified novel genes that respond to skeletal muscle damage, which, given the known biological functions, are likely involved in recovery from and/or adaptation to damaging exercise.My notes: I wonder why all this muscle physiology stuff is so elusive, to quote the authors "In total, 113 genes increased 3 h postexercise, and 34 decreased." That is a lot of stuff going on! Still wondering if you need to damage the muscle for it to increase in size?
Post exercise carbohydrate-protein supplementation: phosphorylation of muscle proteins involved in glycogen synthesis and protein translation.
Ivy JL, Ding Z, Hwang H, Cialdella-Kam LC, Morrison PJ.Exercise Physiology and Metabolism Laboratory, Department of Kinesiology and Health Education, The University of Texas, Austin, Texas 78712-0360, USA. johnivy@mail.utexas.edu The enzymes Akt, mTOR, p70(S6K), rpS6, GSK3, and glycogen synthase interact in the control of protein and/or glycogen synthesis in skeletal muscle, and each has been found to respond to exercise and nutrient supplementation. In the present study, we tested the hypothesis that nutrient supplementation post exercise, in the form of a carbohydrate-protein (CHO-PRO) supplement, would alter the phosphorylation state of these enzymes in a manner that should increase muscle protein and glycogen synthesis above that produced by exercise alone. After a 45 min cycling session followed by sprints and again 15 min later, the subjects (n = 8) ingested 400 ml of a CHO-PRO drink (7.8% dextrose and 1.8% protein-electrolyte) or a placebo drink, as assigned using a randomized, counter-balanced design with repeated measures. Biopsies of the vastus lateralis were taken before exercise and at 45 min of recovery.
At 45 min after supplementation, CHO-PRO treatment yielded greater phosphorylation of Akt (65%), mTOR (86%), rpS6 (85-fold), and GSK3alpha/beta (57%) than pre-exercise levels (p < style="font-weight: bold;">
Conclusion: These results suggest that a post exercise carb and protein (CHO-PRO) supplement alters the phosporylation levels of the enzymes tested in a manner that should accelerate muscle glycogen synthesis and protein initiation during recovery from cycling exercise.
My notes: cool info, but I would like to see this carried out in the future to any performance changes. This would say that it should help. I am sure that is in the pipeline and there is some data already out in that area
The effects of ibuprofen on muscle hypertrophy, strength, and soreness during resistance training.
Krentz JR, Quest B, Farthing JP, Quest DW, Chilibeck PD. High doses of ibuprofen have been shown to inhibit muscle protein synthesis after a bout of resistance exercise. We determined the effect of a moderate dose of ibuprofen (400 mg.d-1) consumed on a daily basis after resistance training on muscle hypertrophy and strength. Twelve males and 6 females (~24 years of age) trained their right and left biceps on alternate days (6 sets of 4-10 repetitions), 5 d.week-1, for 6 weeks.
In a counter-balanced, double-blind design, they were randomized to receive 400 mg.d-1 ibuprofen immediately after training their left or right arm, and a placebo after training the opposite arm the following day. Before- and after-training muscle thickness of both biceps was measured using ultrasound and 1 repetition maximum (1 RM) arm curl strength was determined on both arms.
Subjects rated their muscle soreness daily. There were time main effects for muscle thickness and strength (p < style="font-weight: bold;">
Conclusion: We conclude that a moderate dose of ibuprofen ingested after repeated resistance training sessions does not impair muscle hypertrophy or strength and does not affect ratings of muscle soreness.My Notes: If you would have asked me even a few months ago, I would have said that the use of NSAIDs (like Advil) is not a good idea as it may limit muscle growth (hypertrophy). After talking to some at ACSM, looking at some newer litature, I am thinking it will probably be ok. It may even be beneficial after an acute injury to keep your movement quality better and limit pain, thus reducing the chance on longer term chronic pain ala the neuromatrix of pain. See the following posts on that below
Pain Perception and the Neuromatrix--Guest Blog by Katelin Bigelow
Pre-emptive Analgescis--what is he talking about now?Cellular and molecular events controlling skeletal muscle mass in response to altered use.
Favier FB, Benoit H, Freyssenet D.Unité Physiologie et Physiopathologie de l’Exercice et Handicap, IFR143, Université Jean Monnet, 15 rue Ambroise Paré, 42023, Saint Etienne, cedex 2, France.
Gain or loss of skeletal muscle mass occurs in situations of altered use such as strength training, aging, denervation, or immobilization. This review examines our current understanding of the cellular and molecular events involved in the control of muscle mass under conditions of muscle use and disuse, with particular attention to the effects of resistance exercise/training. The DNA content, which is a critical determinant of protein synthesis by providing the amount of DNA necessary to sustain gene transcription, can be either increased (activation of satellite cells) or decreased (apoptosis) depending on muscle activity and ongoing physiological processes. In addition, several transcription factors are sensitive to functional demand and may control muscle-specific protein expression to promote or repress myofiber enlargement. The control of skeletal muscle mass is also markedly mediated by the regulation of transduction pathways that promote the synthesis and/or the degradation of proteins. Insulin-like growth factor-I plays a key role in this balance by activating the Akt/tuberous sclerosis complex 2/mammalian target of rapamycin pathway.
Conclusion: Stimulation of this pathway leads to the concomitant activation of initiation and elongation factors resulting in the elevation of protein translation and the downregulation of ubiquitin proteasome components through Forkhead-box O transcription factors.
My Notes: Good review (with lots of big words), but the take away is still the same--USE IT OR LOSE IT!
Rock on
Mike N
