No effect of creatine supplementation on human myofibrillar and sarcoplasmic protein synthesis after resistance exercise

2003 ◽  
Vol 285 (5) ◽  
pp. E1089-E1094 ◽  
Author(s):  
Magali Louis ◽  
Jacques R. Poortmans ◽  
Marc Francaux ◽  
Jacques Berré ◽  
Nathalie Boisseau ◽  
...  
Keyword(s):  
Resistance Exercise ◽  
Muscle Hypertrophy ◽  
Muscle Protein ◽  
Creatine Supplementation ◽  
Quadriceps Muscle ◽  
Anabolic Effect ◽  
Leg Extension ◽  
Sarcoplasmic Protein ◽  
Before And After ◽  
Total Creatine

Muscle hypertrophy during resistance training is reportedly increased by creatine supplementation. Having previously failed to find an anabolic effect on muscle protein turnover at rest, either fed or fasted, we have now examined the possibility of a stimulatory effect of creatine in conjunction with acute resistance exercise. Seven healthy men (body mass index, 23 ± 2 kg/m2, 21 ± 1 yr, means ± SE) performed 20 × 10 repetitions of leg extension-flexion at 75% one-repetition maximum in one leg, on two occasions, 4 wk apart, before and after ingesting 21 g/day creatine for 5 days. The subjects ate ∼21 g maltodextrin + 6 g protein/h for 3 h postexercise. We measured incorporation of [1-13C]leucine into quadriceps muscle proteins in the rested and exercised legs. Leg protein breakdown (as dilution of [2H5]phenylalanine) was also assessed in the exercised and rested leg postexercise. Creatine supplementation increased muscle total creatine by ∼21% ( P < 0.01). Exercise increased the synthetic rates of myofibrillar and sarcoplasmic proteins by two- to threefold ( P < 0.05), and leg phenylalanine balance became more positive, but creatine was without any anabolic effect.

Creatine supplementation has no effect on human muscle protein turnover at rest in the postabsorptive or fed states

2003 ◽  
Vol 284 (4) ◽  
pp. E764-E770 ◽  
Author(s):  
Magali Louis ◽  
Jacques R. Poortmans ◽  
Marc Francaux ◽  
Eric Hultman ◽  
Jacques Berré ◽  
...  
Keyword(s):  
Muscle Mass ◽  
Muscle Protein ◽  
Creatine Supplementation ◽  
Quadriceps Muscle ◽  
Protein Breakdown ◽  
Fed State ◽  
Muscle Protein Breakdown ◽  
Before And After ◽  
Total Creatine ◽  
Myofibrillar Protein Synthesis

Dietary creatine supplementation is associated with increases in muscle mass, but the mechanism is unknown. We tested the hypothesis that creatine supplementation enhanced myofibrillar protein synthesis (MPS) and diminished muscle protein breakdown (MPB) in the fed state. Six healthy men (26 ± 7 yr, body mass index 22 ± 4 kg/m2) were studied twice, 2–4 wk apart, before and after ingestion of creatine (21 g/day, 5 days). We carried out two sets of measurements within 5.5 h of both MPS (by incorporation of [1-13C]leucine in quadriceps muscle) and MPB (as dilution of [1-13C]leucine or [2H5]phenylalanine across the forearm); for the first 3 h, the subjects were postabsorptive but thereafter were fed orally (0.3 g maltodextrin and 0.083 g protein · kg body wt−1 · h−1). Creatine supplementation increased muscle total creatine by ∼30% ( P < 0.01). Feeding had significant effects, doubling MPS ( P < 0.001) and depressing MPB by ∼40% ( P < 0.026), but creatine had no effect on turnover in the postabsorptive or fed states. Thus any increase in muscle mass accompanying creatine supplementation must be associated with increased physical activity.

Effects of acute creatine monohydrate supplementation on leucine kinetics and mixed-muscle protein synthesis

2001 ◽  
Vol 91 (3) ◽  
pp. 1041-1047 ◽  
Author(s):  
G. Parise ◽  
S. Mihic ◽  
D. MacLennan ◽  
K. E. Yarasheski ◽  
M. A. Tarnopolsky
Keyword(s):  
Protein Synthesis ◽  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Fat Free Mass ◽  
Whole Body ◽  
Synthetic Rate ◽  
Fractional Synthetic Rate ◽  
Before And After ◽  
Total Creatine ◽  
Plasma Leucine

Creatine monohydrate (CrM) supplementation during resistance exercise training results in a greater increase in strength and fat-free mass than placebo. Whether this is solely due to an increase in intracellular water or whether there may be alterations in protein turnover is not clear at this point. We examined the effects of CrM supplementation on indexes of protein metabolism in young healthy men ( n = 13) and women ( n = 14). Subjects were randomly allocated to CrM (20 g/day for 5 days followed by 5 g/day for 3–4 days) or placebo (glucose polymers) and tested before and after the supplementation period under rigorous dietary and exercise controls. Muscle phosphocreatine, creatine, and total creatine were measured before and after supplementation. A primed-continuous intravenous infusion of l-[1-13C]leucine and mass spectrometry were used to measure mixed-muscle protein fractional synthetic rate and indexes of whole body leucine metabolism (nonoxidative leucine disposal), leucine oxidation, and plasma leucine rate of appearance. CrM supplementation increased muscle total creatine (+13.1%, P < 0.05) with a trend toward an increase in phosphocreatine (+8.8%, P = 0.09). CrM supplementation did not increase muscle fractional synthetic rate but reduced leucine oxidation (−19.6%) and plasma leucine rate of appearance (−7.5%, P < 0.05) in men, but not in women. CrM did not increase total body mass or fat-free mass. We conclude that short-term CrM supplementation may have anticatabolic actions in some proteins (in men), but CrM does not increase whole body or mixed-muscle protein synthesis.

scholarly journals Regional and muscle-specific adaptations in knee extensor hypertrophy using flywheel versus conventional weight-stack resistance exercise

2019 ◽  
Vol 44 (8) ◽  
pp. 827-833 ◽  
Author(s):  
Tommy R. Lundberg ◽  
Maria T. García-Gutiérrez ◽  
Mirko Mandić ◽  
Mats Lilja ◽  
Rodrigo Fernandez-Gonzalo
Keyword(s):  
Resistance Exercise ◽  
Muscle Hypertrophy ◽  
Vastus Lateralis ◽  
Knee Extensor ◽  
Rectus Femoris ◽  
Knee Extension ◽  
Knee Extensors ◽  
Cross Sectional ◽  
Proximal Site ◽  
Before And After

This study compared the effects of the most frequently employed protocols of flywheel (FW) versus weight-stack (WS) resistance exercise (RE) on regional and muscle-specific adaptations of the knee extensors. Sixteen men (n = 8) and women (n = 8) performed 8 weeks (2–3 days/week) of knee extension RE employing FW technology on 1 leg (4 × 7 repetitions), while the contralateral leg performed regular WS training (4 × 8–12 repetitions). Maximal strength (1-repetition maximum (1RM) in WS) and peak FW power were determined before and after training for both legs. Partial muscle volume of vastus lateralis (VL), vastus medialis (VM), vastus intermedius (VI), and rectus femoris (RF) were measured using magnetic resonance imaging. Additionally, quadriceps cross-sectional area was assessed at a proximal and a distal site. There were no differences (P > 0.05) between FW versus WS in muscle hypertrophy of the quadriceps femoris (8% vs. 9%), VL (10% vs. 11%), VM (6% vs. 8%), VI (5% vs. 5%), or RF (17% vs. 17%). Muscle hypertrophy tended (P = 0.09) to be greater at the distal compared with the proximal site, but there was no interaction with exercise method. Increases in 1RM and FW peak power were similar across legs, yet the increase in 1RM was greater in men (31%) than in women (20%). These findings suggest that FW and WS training induces comparable muscle-specific hypertrophy of the knee extensors. Given that these robust muscular adaptations were brought about with markedly fewer repetitions in the FW compared with WS, it seems FW training can be recommended as a particularly time-efficient exercise paradigm.

scholarly journals Exercise May Promote Skeletal Muscle Hypertrophy via Enhancing Leucine-Sensing: Preliminary Evidence

2021 ◽  
Vol 12 ◽  
Author(s):  
Yan Zhao ◽  
Jason Cholewa ◽  
Huayu Shang ◽  
Yueqin Yang ◽  
Xiaomin Ding ◽  
...  
Keyword(s):  
Protein Synthesis ◽  
Resistance Exercise ◽  
Aerobic Exercise ◽  
Protein Concentration ◽  
Muscle Hypertrophy ◽  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Muscle Fibers ◽  
Mtor Signaling ◽  
Treadmill Running

Several studies have indicated a positive effect of exercise (especially resistance exercise) on the mTOR signaling that control muscle protein synthesis and muscle remodeling. However, the relationship between exercise, mTOR activation and leucine-sensing requires further clarification. Two month old Sprague-Dawley rats were subjected to aerobic exercise (treadmill running at 20 m/min, 6° incline for 60 min) and resistance exercise (incremental ladder climbing) for 4 weeks. The gastrocnemius muscles were removed for determination of muscle fibers diameter, cross-sectional area (CSA), protein concentration and proteins involved in muscle leucine-sensing and protein synthesis. The results show that 4 weeks of resistance exercise increased the diameter and CSA of gastrocnemius muscle fibers, protein concentration, the phosphorylation of mTOR (Ser2448), 4E-BP1(Thr37/46), p70S6K (Thr389), and the expression of LeuRS, while aerobic exercise just led to a significant increase in protein concentration and the phosphorylation of 4E-BP1(Thr37/46). Moreover, no difference was found for Sestrin2 expression between groups. The current study shows resistance exercise, but not aerobic exercise, may increase muscle protein synthesis and protein deposition, and induces muscle hypertrophy through LeuRS/mTOR signaling pathway. However, further studies are still warranted to clarify the exact effects of vary intensities and durations of aerobic exercise training.

scholarly journals Stimuli and sensors that initiate skeletal muscle hypertrophy following resistance exercise

2019 ◽  
Vol 126 (1) ◽  
pp. 30-43 ◽  
Author(s):  
Henning Wackerhage ◽  
Brad J. Schoenfeld ◽  
D. Lee Hamilton ◽  
Maarit Lehti ◽  
Juha J. Hulmi
Keyword(s):  
Skeletal Muscle ◽  
Resistance Exercise ◽  
Muscle Damage ◽  
Muscle Hypertrophy ◽  
Muscle Protein ◽  
Large Body ◽  
Focal Adhesions ◽  
Indirect Evidence ◽  
Skeletal Muscle Hypertrophy ◽  
Exercise Induced

One of the most striking adaptations to exercise is the skeletal muscle hypertrophy that occurs in response to resistance exercise. A large body of work shows that a mammalian target of rapamycin complex 1 (mTORC1)-mediated increase of muscle protein synthesis is the key, but not sole, mechanism by which resistance exercise causes muscle hypertrophy. While much of the hypertrophy signaling cascade has been identified, the initiating, resistance exercise-induced and hypertrophy-stimulating stimuli have remained elusive. For the purpose of this review, we define an initiating, resistance exercise-induced and hypertrophy-stimulating signal as “hypertrophy stimulus,” and the sensor of such a signal as “hypertrophy sensor.” In this review we discuss our current knowledge of specific mechanical stimuli, damage/injury-associated and metabolic stress-associated triggers, as potential hypertrophy stimuli. Mechanical signals are the prime hypertrophy stimuli candidates, and a filamin-C-BAG3-dependent regulation of mTORC1, Hippo, and autophagy signaling is a plausible albeit still incompletely characterized hypertrophy sensor. Other candidate mechanosensing mechanisms are nuclear deformation-initiated signaling or several mechanisms related to costameres, which are the functional equivalents of focal adhesions in other cells. While exercise-induced muscle damage is probably not essential for hypertrophy, it is still unclear whether and how such muscle damage could augment a hypertrophic response. Interventions that combine blood flow restriction and especially low load resistance exercise suggest that resistance exercise-regulated metabolites could be hypertrophy stimuli, but this is based on indirect evidence and metabolite candidates are poorly characterized.

scholarly journals Creatine supplementation: effects on blood creatine kinase activity responses to resistance exercise and creatine kinase activity measurement

2009 ◽  
Vol 45 (4) ◽  
pp. 751-757 ◽  
Author(s):  
Marco Machado ◽  
Rafael Pereira ◽  
Felipe Sampaio-Jorge ◽  
Franz Knifis ◽  
Anthony Hackney
Keyword(s):  
Creatine Kinase ◽  
Resistance Exercise ◽  
Kinase Activity ◽  
Training Session ◽  
Creatine Supplementation ◽  
Creatine Kinase Activity ◽  
Exercise Session ◽  
Activity Measurement ◽  
Double Blind Study ◽  
Leg Extension

The purpose of this study was to determine the effects of creatine supplementation and exercise on the integrity of muscle fiber, as well as the effect of the supplementation on the creatine kinase (CK) assay measurement. Forty-nine sedentary individuals participated in a double-blind study and were divided into two groups: C (n=26) received 4x5-day packages of 0.6 g.kg-1 of body weight contained 50% of creatine + 50% of dextrose, and P (n=23) received packages containing only dextrose. On the first day the groups performed a 1RM test for bench press, seated row, leg extension, leg curl and leg press. On D7 they received the supplements. On the fourteenth day, they performed a training session of five exercises, each in three sets of ten repetitions at 75% of 1RM. Blood was collected before (D14) and after the exercise session (D15). Differing levels of blood creatine were tested to determine the influence on the assay measurements of CK. ANOVA and Tukey's post-hoc tests were used to compare groups and different times of study protocol (P<0.05). No changes were observed in CK activity of the groups from D0, D7 and D14. On D15 CK activity increases 140% (women) and 200% (men). There was no difference in CK activity between groups. Blood creatine levels up to 5mM produced no significant effect on CK assay results. CK activity increased after resistance exercise, while creatine supplementation produced no difference in the muscle cellular integrity nor compromised assay methodology.

Creatine Supplementation: Exploring the Role of the Creatine Kinase/Phosphocreatine System in Human Muscle

2001 ◽  
Vol 26 (S1) ◽  
pp. S79-S102 ◽  
Author(s):  
Peter Hespel ◽  
Bert Op ‘t Eijnde ◽  
Wim Derave ◽  
Erik A. Richter
Keyword(s):  
Creatine Kinase ◽  
Muscle Hypertrophy ◽  
Muscle Protein ◽  
Muscle Relaxation ◽  
Glycogen Synthesis ◽  
Creatine Supplementation ◽  
Mechanisms Of Action ◽  
The Past ◽  
Creatine Metabolism

The effect of oral creatine supplementation on high-intensity exercise performance has been extensively studied over the past ten years and its ergogenic potential in young healthy subjects is now well documented. Recently, research has shifted from performance evaluation towards elucidating the mechanisms underlying enhanced muscle functional capacity after creatine supplementation. In this review, we attempt to summarise recent advances in the understanding of potential mechanisms of action of creatine supplementation at the level of skeletal muscle cells. By increasing intracellular creatine content, oral creatine ingestion conceivably stimulates operation of the creatine kinase (CK)/phosphocreatine (PCr) system, which in turn facilitates muscle relaxation. Furthermore, evidence is accumulating to suggest that creatine supplementation can beneficially impact on muscle protein and glycogen synthesis. Thus, muscle hypertrophy and glycogen supercompensation a1'e candidate factors to explain the ergogenic potential of creatine ingestion. Additional issues discussed in this review are the fibre-type specificity of muscle creatine metabolism, the identification of responders versus non-responders to creatine intake, and the scientific background concerning potential side effects of creatine supplementation.

scholarly journals Improving muscle mass: response of muscle metabolism to exercise, nutrition and anabolic agents

2008 ◽  
Vol 44 ◽  
pp. 85-98 ◽  
Author(s):  
Kevin D. Tipton ◽  
Arny A. Ferrando
Keyword(s):  
Amino Acids ◽  
Resistance Exercise ◽  
Muscle Mass ◽  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Creatine Supplementation ◽  
Healthy Weight ◽  
Anabolic Agents ◽  
Increase Muscle Mass ◽  
Positive Balance

Muscle mass is critical for athletic performance and, perhaps more importantly for most, health and survival. The metabolic basis for a change in muscle mass is an increase in net muscle protein balance (termed NBAL). NBAL is the difference between MPS (muscle protein synthesis) and MPB (muscle protein breakdown). Thus an increase in MPS and/or a decrease in MPB are necessary for NBAL to increase, leading to accretion of muscle proteins. In particular, accretion of myofibrillar proteins is necessary. NBAL responds to exercise, feeding and other factors. In healthy, weight-stable adults, muscle mass remains constant because periods of positive balance following feeding are countered by periods of negative balance during fasting. A combination of resistance exercise and nutrition is a potent anabolic stimulus through stimulation of MPS from amino acids and attenuation of MPB by carbohydrates. Increased muscle mass results from the accumulation of small amounts of protein in response to each bout of exercise combined with nutrient intake. The magnitude of the response may be influenced by factors other than just the amount of a nutrient ingested. Timing of ingestion, co-ingestion of nutrients and the type of protein may all influence protein accretion. Testosterone is a potent anabolic stimulus primarily through improvement in re-utilization of amino acids from MPB. There is a general lack of efficacy in studies assessing the potential for growth hormone, androstenedione and dehydroepiandrostenedione to increase muscle mass. Creatine supplementation is clearly an effective means to increase muscle mass, especially in combination with resistance exercise, however the mechanisms remain unclear. Results from acute metabolic studies provide useful information for estimation of the efficacy of anabolic agents.

scholarly journals Twelve-week combined resistance and aerobic training confers greater benefits than aerobic training alone in nondialysis CKD

2018 ◽  
Vol 314 (6) ◽  
pp. F1188-F1196 ◽  
Author(s):  
Emma L. Watson ◽  
Douglas W. Gould ◽  
Thomas J. Wilkinson ◽  
Soteris Xenophontos ◽  
Amy L. Clarke ◽  
...  
Keyword(s):  
Resistance Exercise ◽  
Aerobic Exercise ◽  
Aerobic Training ◽  
Estimated Glomerular Filtration Rate ◽  
Control Period ◽  
Knee Extensor ◽  
Quadriceps Muscle ◽  
Leg Extension ◽  
Knee Extensor Strength ◽  
Knee Extensor Muscle Strength

There is a growing consensus that patients with chronic kidney disease (CKD) should engage in regular exercise, but there is a lack of formal guidelines. In this report, we determined whether combined aerobic and resistance exercise would elicit superior physiological gains, in particular muscular strength, compared with aerobic training alone in nondialysis CKD. Nondialysis patients with CKD stages 3b–5 were randomly allocated to aerobic exercise {AE, n = 21; 9 men; median age 63 [interquartile range (IQR) 58–71] yr; median estimated glomerular filtration rate (eGFR) 24 (IQR 20–30) ml·min−1·1.73 m−2} or combined exercise [CE, n = 20, 9 men, median age 63 (IQR 51–69) yr, median eGFR 27 (IQR 22–32) ml·min−1·1.73 m−2], preceded by a 6-wk run-in control period. Patients then underwent 12 wk of supervised AE (treadmill, rowing, or cycling exercise) or CE training (as AE plus leg extension and leg press exercise) performed three times per week. Outcome assessments of knee extensor muscle strength, quadriceps muscle volume, exercise capacity, and central hemodynamics were performed at baseline, following the 6-wk control period, and at the end of the intervention. AE and CE resulted in significant increases in knee extensor strength of 16 ± 19% (mean ± SD; P = 0.001) and 48 ± 37% ( P < 0.001), respectively, which were greater after CE ( P = 0.02). AE and CE resulted in 5 ± 7% ( P = 0.04) and 9 ± 7% ( P < 0.001) increases in quadriceps volume, respectively ( P < 0.001), which were greater after CE ( P = 0.01). Both AE and CE increased distance walked in the incremental shuttle walk test [28 ± 44 m ( P = 0.01) and 32 ± 45 m ( P = 0.01), respectively]. In nondialysis CKD, the addition of resistance exercise to aerobic exercise confers greater increases in muscle mass and strength than aerobic exercise alone.

Sign in / Sign up

Export Citation Format

Share Document