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Association of the gut microbiota and fecal short-chain fatty acids with skeletal muscle mass and strength in children.
Chen, F, Li, Q, Chen, Y, Wei, Y, Liang, J, Song, Y, Shi, L, Wang, J, Mao, L, Zhang, B, et al
FASEB journal : official publication of the Federation of American Societies for Experimental Biology. 2022;(1):e22109
Abstract
We aimed to investigate whether the gut microbiota and fecal short-chain fatty acids (SCFAs) are associated with skeletal muscle mass and strength in healthy Chinese children aged 6-9 years. In this study, 412 children were enrolled. 16S rRNA gene sequencing was used to characterize the gut microbiota compositions. Fecal SCFAs were quantified using high-performance liquid chromatography. Dual X-ray absorptiometry was used to measure the total body lean soft tissue mass (TSM), total body fat mass (TBF), appendicular skeletal muscle mass (ASM), and appendicular fat mass (AFM). TSM/height2 (TSMI), ASM/height2 (ASMI), TSM/weight (TSMR), ASM/weight (ASMR), and the ratio of TSM/TBF and ASM/AFM were calculated. Handgrip strength (HGS) was measured using the Jamar® Plus+ Hand Dynamometer. A multiple regression analysis after adjustment for covariates and multiple test correction showed some operational taxonomic units in partial least squares models identified by Multivariate methods with Unbiased Variable selection analysis such as genera of Faecalibacterium, Lachnospira, Lachnospiraceae_ND3007_group, and Lachnospiraceae_UCG-004 were positively correlated with at least one measure of TSM, TSMI, ASM, ASMI, and ASMI Z-score (β: 0.103-0.143, pFDR : .008-.032) but negatively correlated with at least one measure of TSMR, TSM/TBF, ASMR, ASM/AFM, and ASMR Z-score (β: -0.185 to 0.124, pFDR = .008-.045). Children with higher fecal butyric acid, acetic acid, and total SCFA levels exhibited higher TSM, ASM, TSMI, ASMI, and ASMI Z-score and lower TSM/TBF, ASM/AFM, TSMR, ASMR, and ASMR Z-score. However, after additional adjustment for TBF or body mass index, only the associations for Faecalitalea and Pyramidobacter still existed. Mediation analysis suggested that total body fat significantly mediated 66.3%-95.3% of the estimated association of microbiota and SCFAs with TSM, ASM, and ASMI Z-score. Our results suggest that the associations of gut microbiota and SCFAs with skeletal muscle quality in children may largely depend upon on total body fat content.
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Leucine Supplementation Increases Muscle Strength and Volume, Reduces Inflammation, and Affects Wellbeing in Adults and Adolescents with Cerebral Palsy.
Theis, N, Brown, MA, Wood, P, Waldron, M
The Journal of nutrition. 2021;(1):59-64
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Abstract
BACKGROUND Spastic cerebral palsy (CP) is characterized by muscle weakness owing, in part, to a blunted muscle protein synthetic response. This might be normalized by long-term leucine supplementation. OBJECTIVES The study assessed the effects of 10 wk leucine supplementation in adolescents and adults with CP. METHODS The study was a single-center randomized controlled trial. Twenty-four participants were randomly assigned to a control group (n = 12) or a leucine group (n = 12). l-Leucine (192 mg/kg body mass) was dissolved in water and administered daily for 10 wk. The primary outcome measures of elbow flexor muscle strength and muscle volume (measured by 3D ultrasound technique) and inflammation [C-reactive protein (CRP) concentration] were assessed before and after the 10 wk, alongside the secondary outcomes of body composition (measured by CP-specific skinfold assessment), metabolic rate (measured by indirect calorimetry), and wellbeing (measured by a self-reported daily questionnaire). Data were compared via a series of 2-factor mixed ANOVAs. RESULTS Twenty-one participants completed the intervention (control group: n = 11, mean ± SD age: 18.3 ± 2.8 y, body mass: 48.8 ± 11.9 kg, 45% male; leucine group: n = 10, age: 18.6 ± 1.7 y, body mass: 58.3 ± 20.2 kg, 70% male). After 10 wk, there was a 25.4% increase in strength (P = 0.019) and a 3.6% increase in muscle volume (P = 0.001) in the leucine group, with no changes in the control group. This was accompanied by a 59.1% reduction in CRP (P = 0.045) and improved perceptions of wellbeing (P = 0.006) in the leucine group. No changes in metabolism or body composition were observed in either group (P > 0.05). CONCLUSIONS Improvements in muscle strength and volume with leucine supplementation might provide important functional changes for adults and adolescents with CP and could be partly explained by reduced inflammation. The improved wellbeing highlights its capacity to improve the quality of daily living. This trial was registered at clinicaltrials.gov as NCT03668548.
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RaceRunning training improves stamina and promotes skeletal muscle hypertrophy in young individuals with cerebral palsy.
Hjalmarsson, E, Fernandez-Gonzalo, R, Lidbeck, C, Palmcrantz, A, Jia, A, Kvist, O, Pontén, E, von Walden, F
BMC musculoskeletal disorders. 2020;(1):193
Abstract
BACKGROUND Individuals with cerebral palsy (CP) are less physically active, spend more time sedentary and have lower cardiorespiratory endurance as compared to typically developed individuals. RaceRunning enables high-intensity exercise in individuals with CP with limited or no walking ability, using a three-wheeled running bike with a saddle and a chest plate for support, but no pedals. Training adaptations using this type of exercise are unknown. METHODS Fifteen adolescents/young adults (mean age 16, range 9-29, 7 females/8 males) with CP completed 12 weeks, two sessions/week, of RaceRunning training. Measurements of cardiorespiratory endurance (6-min RaceRunning test (6-MRT), average and maximum heart rate, rate of perceived exertion using the Borg scale (Borg-RPE)), skeletal muscle thickness (ultrasound) of the thigh (vastus lateralis and intermedius muscles) and lower leg (medial gastrocnemius muscle) and passive range of motion (pROM) of hip, knee and ankle were collected before and after the training period. RESULTS Cardiorespiratory endurance increased on average 34% (6-MRT distance; pre 576 ± 320 m vs. post 723 ± 368 m, p < 0.001). Average and maximum heart rate and Borg-RPE during the 6-MRT did not differ pre vs. post training. Thickness of the medial gastrocnemius muscle increased 9% in response to training (p < 0.05) on the more-affected side. Passive hip flexion increased (p < 0.05) on the less-affected side and ankle dorsiflexion decreased (p < 0.05) on the more affected side after 12 weeks of RaceRunning training. CONCLUSIONS These results support the efficacy of RaceRunning as a powerful and effective training modality in individuals with CP, promoting both cardiorespiratory and peripheral adaptations.
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Impact of protein supplementation during endurance training on changes in skeletal muscle transcriptome.
Knuiman, P, Hangelbroek, R, Boekschoten, M, Hopman, M, Mensink, M
BMC genomics. 2020;(1):397
Abstract
BACKGROUND Protein supplementation improves physiological adaptations to endurance training, but the impact on adaptive changes in the skeletal muscle transcriptome remains elusive. The present analysis was executed to determine the impact of protein supplementation on changes in the skeletal muscle transcriptome following 5-weeks of endurance training. RESULTS Skeletal muscle tissue samples from the vastus lateralis were taken before and after 5-weeks of endurance training to assess changes in the skeletal muscle transcriptome. One hundred and 63 genes were differentially expressed after 5-weeks of endurance training in both groups (q-value< 0.05). In addition, the number of genes differentially expressed was higher in the protein group (PRO) (892, q-value< 0.05) when compared with the control group (CON) (440, q-value< 0.05), with no time-by-treatment interaction effect (q-value> 0.05). Endurance training primarily affected expression levels of genes related to extracellular matrix and these changes tended to be greater in PRO than in CON. CONCLUSIONS Protein supplementation subtly impacts endurance training-induced changes in the skeletal muscle transcriptome. In addition, our transcriptomic analysis revealed that the extracellular matrix may be an important factor for skeletal muscle adaptation in response to endurance training. This trial was registered at clinicaltrials.gov as NCT03462381, March 12, 2018. TRIAL REGISTRATION This trial was registered at clinicaltrials.gov as NCT03462381.
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A single injection of vitamin D3 improves insulin sensitivity and β-cell function but not muscle damage or the inflammatory and cardiovascular responses to an acute bout of resistance exercise in vitamin D-deficient resistance-trained males.
Ashtary-Larky, D, Kheirollah, A, Bagheri, R, Ghaffari, MA, Mard, SA, Hashemi, SJ, Mir, I, Wong, A
The British journal of nutrition. 2020;(4):394-401
Abstract
Vitamin D deficiency is now a recognised problem affecting multiple physiological functions. The aim of the present study was to evaluate the effect of a single dose of vitamin D3 injection on the inflammatory, muscular damage, metabolic and cardiovascular responses to an acute bout of resistance exercise (RE) in vitamin D-deficient resistance-trained males. Blood samples from fourteen vitamin D-deficient resistance-trained males were obtained during two separate trials: lower vitamin D (LVD) and higher vitamin D (HVD, after vitamin D3 injection). Metabolic, inflammatory, muscle damage and cardiovascular markers were evaluated at baseline, immediately and 1 h after RE. There were significant trial-by-time interactions for insulin and homeostatic model assessment of insulin resistance (HOMA-IR) which significantly (P < 0·05) declined for 1 h after RE in the HVD trial compared with the LVD trial. Homeostasis model assessment of β-cell function (HOMA-β) declines at 1 h post-RE in the HVD trial. There was also a time effect for blood sugar which significantly (P < 0·05) decreased and for creatine kinase, lactate dehydrogenase and IL-6 which increased significantly 1 h post-RE in both trials. There were no significant changes in other inflammatory and cardiovascular markers following both trials. A single injection of vitamin D3 improved insulin resistance and β-cell function following RE in previously vitamin D-deficient resistance-trained males. Conversely, the injection did not change muscle damage and the inflammatory response to acute RE. Intramuscular vitamin D replacement may have key implications for the promotion of glucose metabolism and lowering the risk of diabetes in vitamin D-deficient individuals.
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Modulation of Countermovement Jump-Derived Markers of Neuromuscular Function With Concurrent vs. Single-Mode Resistance Training.
Pattison, KJ, Drinkwater, EJ, Bishop, DJ, Stepto, NK, Fyfe, JJ
Journal of strength and conditioning research. 2020;(6):1497-1502
Abstract
Pattison, KJ, Drinkwater, EJ, Bishop, DJ, Stepto, NK, and Fyfe, JJ. Modulation of countermovement jump-derived markers of neuromuscular function with concurrent vs. single-mode resistance training. J Strength Cond Res 34(6): 1497-1502, 2020-This study assessed changes in countermovement jump (CMJ)-derived markers of neuromuscular function with concurrent training vs. resistance training (RT) alone and determined associations between changes in CMJ parameters and other neuromuscular adaptations (e.g., maximal strength gain). Twenty-three recreationally active men performed 8 weeks of RT alone (RT group, n = 8) or combined with either high-intensity interval training cycling (HIIT + RT group, n = 8) or moderate-intensity continuous cycling (MICT + RT group, n = 7). Maximal strength and CMJ performance were assessed before (PRE), after 4 weeks of training (MID), and >72 hours (maximal strength) or >5-7 days (CMJ performance) after (POST) the training intervention. Improvements in CMJ relative peak force from both PRE to MID and PRE to POST were attenuated for both HIIT + RT (effect size [ES]: -0.44; ±90% confidence limit, ±0.51 and ES: -0.72; ±0.61, respectively) and MICT + RT (ES: -0.74; ±0.49 and ES: -1.25; ±0.63, respectively). Compared with RT alone, the change in the flight time to contraction time ratio (FT:CT) was attenuated from PRE to MID for MICT + RT (ES: -0.38; ±0.42) and from PRE to POST for both MICT + RT (ES: -0.60; ±0.55) and HIIT + RT (ES: -0.75; ±0.30). PRE to POST changes in both CMJ relative peak force and flight time:contraction time (F:C) ratio were also associated with relative 1 repetition maximum leg press strength gain (r = 0.26 and 0.19, respectively). These findings highlight the utility of CMJ testing for monitoring interference to improvements in neuromuscular function with concurrent training.
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Higher Muscle Mass Implies Increased Free-Thyroxine to Free-Triiodothyronine Ratio in Subjects With Overweight and Obesity.
Zupo, R, Castellana, F, Sardone, R, Lampignano, L, Paradiso, S, Giagulli, VA, Triggiani, V, Di Lorenzo, L, Giannelli, G, De Pergola, G
Frontiers in endocrinology. 2020;:565065
Abstract
UNLABELLED Thyroid hormones control both metabolic pathways and body composition, whereas little knowledge is available about the possible influence of skeletal muscle mass (MM) on thyroid hormone metabolism and circulating levels. This was a cross-sectional study conducted at the Population Health Unit of the National Institute of Gastroenterology IRCCS "S. de Bellis" (Italy) and investigating the extent to which skeletal MM affects thyroid function in obesity. Two hundred twenty-seven consecutive healthy volunteers (155 women and 72 men) with overweight and obesity (BMI ≥ 25 kg/m2) and taking no medication or supplement were assessed for hormone, metabolic and routine laboratory parameters. Body composition parameters were collected by using bioelectrical impedance analysis (BIA). MM was directly related to the body mass index (BMI), waist circumference (WC), insulin, triglycerides, uric acid and free-triiodothyronine (FT3) serum levels, FT3 to the free-thyroxine (FT4) ratio, and insulin-resistance (HOMA-IR), and inversely related to age, total, and HDL-cholesterol serum levels. Multiple regression models confirmed the relationship between MM and the FT3 to FT4 ratio, independently of age, BMI, TSH, triglycerides, and insulin serum levels. The same analyses run by gender showed that this relationship maintained significance only in men. Increased skeletal MM in obesity results in improved thyroid activity mediated by increased T4 conversion to T3, and higher FT3 circulating levels, particularly in men. In conclusion, preserving a greater skeletal MM in obesity helps to enhance thyroid activity. CLINICAL TRIAL REGISTRATION ClinicalTrials.gov, identifier NCT04327375.
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Effect of Acute Beetroot Juice Supplementation on Bench Press Power, Velocity, and Repetition Volume.
Williams, TD, Martin, MP, Mintz, JA, Rogers, RR, Ballmann, CG
Journal of strength and conditioning research. 2020;(4):924-928
Abstract
Williams, TD, Martin, MP, Mintz, JA, Rogers, RR, and Ballmann, CG. Effect of acute beetroot juice supplementation on bench press power, velocity, and repetition volume. J Strength Cond Res 34(4): 924-928, 2020-The purpose of this study was to examine the effects of acute beetroot juice (BRJ) supplementation on power, velocity, and repetitions to failure (RTF) during bench press exercise. Resistance-trained male subjects (n = 11) were recruited for this study. Using a double-blinded, counterbalanced, crossover study design, subjects were supplemented with either 70 ml of BRJ or placebo (PL; black currant juice) 2 hours before exercise. During each exercise trial, subjects began by completing 2 sets × 2 repetitions of bench press at 70% 1 repetition maximum (1RM) with maximum explosive intent. Barbell velocity and power were measured using a linear position transducer. Subjects then completed 3 sets × RTF at 70% 1RM separated by 2 minutes of rest between each set. Maximum mean power, velocity, and repetitions were analyzed. Mean velocity (p = 0.011; effect size [ES] = 0.54) and mean power (p = 0.015; ES = 0.51) were significantly higher with BRJ when compared with PL. Total RTF (p = 0.002; ES = 0.46) was higher during the BRJ condition vs. PL. Results indicate that acute BRJ supplementation positively impacts velocity, power, and total repetitions during free-weight bench press exercise.
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Effects of Different Weekly Sets-Equated Resistance Training Frequencies on Muscular Strength, Muscle Mass, and Body Fat in Older Women.
Pina, FLC, Nunes, JP, Schoenfeld, BJ, Nascimento, MA, Gerage, AM, Januário, RSB, Carneiro, NH, Cyrino, ES, Oliveira, AR
Journal of strength and conditioning research. 2020;(10):2990-2995
Abstract
Pina, FLC, Nunes, JP, Schoenfeld, BJ, Nascimento, MA, Gerage, AM, Januário, RSB, Carneiro, NH, Cyrino, ES, and Oliveira, AR. Effects of different weekly sets-equated resistance training frequencies on muscular strength, muscle mass and body fat in older women. J Strength Cond Res 34(10): 2990-2995, 2020-The aim of this study was to analyze the effects of different resistance training (RT) frequencies (2 vs. 3 times per week) with an equivalent number of weekly sets performed between conditions on muscular strength and body composition in older women. Forty-seven older women (65 ± 4 years) were divided into 2 groups that performed a 12-week RT program either 2 (G2x and 3 sets) or 3 (G3x and 2 sets) times per week. The groups were evaluated before and after study on measures of body composition through dual-energy x-ray absorptiometry, and muscular strength through one repetition maximum (1RM) testing. Lean soft tissue was significantly increased in both groups (G2x = +1.7%, G3x = +1.7%), while only G3x reduced body fat after the intervention period (G2x = -0.7%, G3x = -2.9%). Similarly, significant increases were noted between conditions for 1RM scores in bench press (G2x = +11.8%, G3x = +11.9%) and knee extension (G2x = +17.4%, G3x = +10.8%). The results indicate that performing 2 or 3 RT sessions per week promotes similar improvements in muscular outcomes, while training more frequently may reduce body fat after 12 weeks of weekly sets-equated RT in untrained older women.
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Redundancy in regulation of lipid accumulation in skeletal muscle during prolonged fasting in obese men.
Høgild, ML, Gudiksen, A, Pilegaard, H, Stødkilde-Jørgensen, H, Pedersen, SB, Møller, N, Jørgensen, JOL, Jessen, N
Physiological reports. 2019;(21):e14285
Abstract
Fasting in human subjects shifts skeletal muscle metabolism toward lipid utilization and accumulation, including intramyocellular lipid (IMCL) deposition. Growth hormone (GH) secretion amplifies during fasting and promotes lipolysis and lipid oxidation, but it is unknown to which degree lipid deposition and metabolism in skeletal muscle during fasting depends on GH action. To test this, we studied nine obese but otherwise healthy men thrice: (a) in the postabsorptive state ("CTRL"), (b) during 72-hr fasting ("FAST"), and (c) during 72-hr fasting and treatment with a GH antagonist (GHA) ("FAST + GHA"). IMCL was assessed by magnetic resonance spectroscopy (MRS) and blood samples were drawn for plasma metabolomics assessment while muscle biopsies were obtained for measurements of regulators of substrate metabolism. Prolonged fasting was associated with elevated GH levels and a pronounced GHA-independent increase in circulating medium- and long-chain fatty acids, glycerol, and ketone bodies indicating increased supply of lipid intermediates to skeletal muscle. Additionally, fasting was associated with a release of short-, medium-, and long-chain acylcarnitines to the circulation from an increased β-oxidation. This was consistent with a ≈55%-60% decrease in pyruvate dehydrogenase (PDHa) activity. Opposite, IMCL content increased ≈75% with prolonged fasting without an effect of GHA. We suggest that prolonged fasting increases lipid uptake in skeletal muscle and saturates lipid oxidation, both favoring IMCL deposition. This occurs without a detectable effect of GHA on skeletal muscle lipid metabolism.