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Archacki D, Zieliński J, Ciekot-Sołtysiak M, Zarębska EA, Kusy K. Sex Differences in the Energy System Contribution during Sprint Exercise in Speed-Power and Endurance Athletes. J Clin Med 2024; 13:4812. [PMID: 39200953 PMCID: PMC11355823 DOI: 10.3390/jcm13164812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2024] [Revised: 08/10/2024] [Accepted: 08/12/2024] [Indexed: 09/02/2024] Open
Abstract
Background/Objectives: A high level of specific metabolic capacity is essential for maximal sprinting in both male and female athletes. Various factors dictate sex differences in maximal power production and energy utilization. This study aims to compare the contribution of energy systems between male and female athletes with similar sport-specific physiological adaptations during a 15-s sprint exercise. Methods: The endurance group consisted of 17 males (23 ± 7 y) and 17 females (20 ± 2 y). The speed-power group included 14 males (21.1 ± 2.6 y) and 14 females (20 ± 3 y). The contribution of phosphagen, glycolytic, and aerobic systems was determined using the three-component PCr-LA-O2 method. Results: Significant differences were observed in the energy expenditure for all systems and total energy expenditure between males and females in both groups (p = 0.001-0.013). The energy expenditure in kJ for individual systems (phosphagen-glycolytic-aerobic) was 35:25:7 vs. 20:16:5 in endurance males vs. female athletes, respectively. In the speed-power group, male athletes expended 33:37:6 kJ and female athletes expended 21:25:4 kJ, respectively. The percentage proportions did not differ between males and females in any system. The contribution of the phosphagen-glycolytic-aerobic systems was 52:37:11 vs. 48:39:13 in endurance male and female athletes, respectively. For speed-power males vs. female athletes, the proportions were 42:50:8 vs. 41:50:9, respectively. Conclusions: Despite the differences in body composition, mechanical output, and absolute energy expenditure, the energy system contribution appears to have a similar metabolic effect between male and female athletes engaged in sprint exercises with similar sport-related adaptations. The magnitude and profile of sex differences are related to sports discipline.
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Affiliation(s)
- Damian Archacki
- Department of Athletics, Strength and Conditioning, Poznan University of Physical Education, Królowej Jadwigi Street 27/39, 61-871 Poznań, Poland; (J.Z.); (M.C.-S.); (E.A.Z.); (K.K.)
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2
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Nemoto S, Nakabo T, Tashiro N, Kishino A, Yoshikawa A, Nakamura D, Geshi E. Relationship among muscle strength, muscle endurance, and skeletal muscle oxygenation dynamics during ramp incremental cycle exercise. Sci Rep 2024; 14:11676. [PMID: 38778135 PMCID: PMC11111797 DOI: 10.1038/s41598-024-61529-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Accepted: 05/07/2024] [Indexed: 05/25/2024] Open
Abstract
Peak oxygen uptake (VO2), evaluated as exercise tolerance, is a strong predictor of life prognosis regardless of health condition. Several previous studies have reported that peak VO2 is higher in those with a greater decrease in muscle oxygen saturation (SmO2) in the active muscles during incremental exercise. However, the skeletal muscle characteristics of individuals exhibiting a greater decrease in SmO2 during active muscle engagement in incremental exercise remain unclear. This study aimed to clarify the relationship among muscle strength, muscle endurance, and skeletal muscle oxygenation dynamics in active leg muscles during incremental exercise. Twenty-four healthy young men were included and categorized into the non-moderate-to-high muscular strength and endurance group (those with low leg muscle strength, endurance, or both; n = 11) and the moderate-to-high muscular strength and endurance group (those with both moderate-to-high leg muscle strength and endurance; n = 13). All participants underwent cardiopulmonary exercise testing combined with near-infrared spectroscopy to assess whole-body peak VO2 and the change in SmO2 at the lateral vastus lateralis from rest to each exercise stage as skeletal muscle oxygenation dynamics. A linear mixed-effects model, with the change in SmO2 from rest to each stage as the dependent variable, individual participants as random effects, and group and exercise load as fixed effects, revealed significant main effects for both group (P = 0.001) and exercise load (P < 0.001) as well as a significant interaction between the two factors (P < 0.001). Furthermore, multiple-comparison test results showed that the change in SmO2 from rest to 40%-100% peak VO2 was significantly higher in the moderate-to-high muscular strength and endurance group than in the non-moderate-to-high muscular strength and endurance group. Maintaining both muscle strength and endurance at moderate or higher levels contributes to high skeletal muscle oxygenation dynamics (i.e., greater decrease in SmO2) during moderate- or high-intensity exercise.
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Affiliation(s)
- Shinji Nemoto
- Department of Physical Therapy, Showa University School of Nursing and Rehabilitation Sciences, 1865 Tokaichiba-cho, Midori-ku, Yokohama, Kanagawa, 226-8555, Japan.
| | - Tohru Nakabo
- Department of Physical Therapy, Showa University School of Nursing and Rehabilitation Sciences, 1865 Tokaichiba-cho, Midori-ku, Yokohama, Kanagawa, 226-8555, Japan
| | - Naonori Tashiro
- Division of Health Science Education, Showa University School of Nursing and Rehabilitation Sciences, Yokohama, Japan
| | - Asami Kishino
- Department of Physical Therapy, Showa University School of Nursing and Rehabilitation Sciences, 1865 Tokaichiba-cho, Midori-ku, Yokohama, Kanagawa, 226-8555, Japan
| | - Akira Yoshikawa
- Division of Health Science Education, Showa University School of Nursing and Rehabilitation Sciences, Yokohama, Japan
| | - Daisuke Nakamura
- Department of Physical Therapy, Showa University School of Nursing and Rehabilitation Sciences, 1865 Tokaichiba-cho, Midori-ku, Yokohama, Kanagawa, 226-8555, Japan
| | - Eiichi Geshi
- Office of Institutional Research, Showa University, Tokyo, Japan
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Barbi C, Temesi J, Giuriato G, Laginestra FG, Martignon C, Moro T, Schena F, Venturelli M, Vernillo G. Skeletal muscle fiber type and TMS-induced muscle relaxation in unfatigued and fatigued knee-extensor muscles. Am J Physiol Regul Integr Comp Physiol 2024; 326:R438-R447. [PMID: 38525536 DOI: 10.1152/ajpregu.00174.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 03/14/2024] [Accepted: 03/15/2024] [Indexed: 03/26/2024]
Abstract
The force drop after transcranial magnetic stimulation (TMS) delivered to the motor cortex during voluntary muscle contractions could inform about muscle relaxation properties. Because of the physiological relation between skeletal muscle fiber-type distribution and size and muscle relaxation, TMS could be a noninvasive index of muscle relaxation in humans. By combining a noninvasive technique to record muscle relaxation in vivo (TMS) with the gold standard technique for muscle tissue sampling (muscle biopsy), we investigated the relation between TMS-induced muscle relaxation in unfatigued and fatigued states, and muscle fiber-type distribution and size. Sixteen participants (7F/9M) volunteered to participate. Maximal knee-extensor voluntary isometric contractions were performed with TMS before and after a 2-min sustained maximal voluntary isometric contraction. Vastus lateralis muscle tissue was obtained separately from the participants' dominant limb. Fiber type I distribution and relative cross-sectional area of fiber type I correlated with TMS-induced muscle relaxation at baseline (r = 0.67, adjusted P = 0.01; r = 0.74, adjusted P = 0.004, respectively) and normalized TMS-induced muscle relaxation as a percentage of baseline (r = 0.50, adjusted P = 0.049; r = 0.56, adjusted P = 0.031, respectively). The variance in the normalized peak relaxation rate at baseline (59.8%, P < 0.001) and in the fatigue resistance (23.0%, P = 0.035) were explained by the relative cross-sectional area of fiber type I to total fiber area. Fiber type I proportional area influences TMS-induced muscle relaxation, suggesting TMS as an alternative method to noninvasively inform about skeletal muscle relaxation properties.NEW & NOTEWORTHY Transcranial magnetic stimulation (TMS)-induced muscle relaxation reflects intrinsic muscle contractile properties by interrupting the drive from the central nervous system during voluntary muscle contractions. We showed that fiber type I proportional area influences the TMS-induced muscle relaxation, suggesting that TMS could be used for the noninvasive estimation of muscle relaxation in unfatigued and fatigued human muscles when the feasibility of more direct method to study relaxation properties (i.e., muscle biopsy) is restricted.
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Affiliation(s)
- Chiara Barbi
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - John Temesi
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, United Kingdom
| | - Gaia Giuriato
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
- Surgical, Medical and Dental Department of Morphological Sciences Related to Transplant, Oncology and Regenerative Medicine, University of Modena and Reggio Emilia, Modena, Italy
| | | | - Camilla Martignon
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Tatiana Moro
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Federico Schena
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Massimo Venturelli
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, United States
| | - Gianluca Vernillo
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milan, Italy
- Department of Social Sciences, University of Alberta, Camrose, Alberta, Canada
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Noone J, Mucinski JM, DeLany JP, Sparks LM, Goodpaster BH. Understanding the variation in exercise responses to guide personalized physical activity prescriptions. Cell Metab 2024; 36:702-724. [PMID: 38262420 DOI: 10.1016/j.cmet.2023.12.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 12/11/2023] [Accepted: 12/20/2023] [Indexed: 01/25/2024]
Abstract
Understanding the factors that contribute to exercise response variation is the first step in achieving the goal of developing personalized exercise prescriptions. This review discusses the key molecular and other mechanistic factors, both extrinsic and intrinsic, that influence exercise responses and health outcomes. Extrinsic characteristics include the timing and dose of exercise, circadian rhythms, sleep habits, dietary interactions, and medication use, whereas intrinsic factors such as sex, age, hormonal status, race/ethnicity, and genetics are also integral. The molecular transducers of exercise (i.e., genomic/epigenomic, proteomic/post-translational, transcriptomic, metabolic/metabolomic, and lipidomic elements) are considered with respect to variability in physiological and health outcomes. Finally, this review highlights the current challenges that impede our ability to develop effective personalized exercise prescriptions. The Molecular Transducers of Physical Activity Consortium (MoTrPAC) aims to fill significant gaps in the understanding of exercise response variability, yet further investigations are needed to address additional health outcomes across all populations.
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Affiliation(s)
- John Noone
- Translational Research Institute, AdventHealth, Orlando, FL 32804, USA
| | | | - James P DeLany
- Translational Research Institute, AdventHealth, Orlando, FL 32804, USA
| | - Lauren M Sparks
- Translational Research Institute, AdventHealth, Orlando, FL 32804, USA
| | - Bret H Goodpaster
- Translational Research Institute, AdventHealth, Orlando, FL 32804, USA.
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5
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Nuzzo JL. Sex differences in skeletal muscle fiber types: A meta-analysis. Clin Anat 2024; 37:81-91. [PMID: 37424380 DOI: 10.1002/ca.24091] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 06/20/2023] [Accepted: 06/24/2023] [Indexed: 07/11/2023]
Abstract
Biopsies have been acquired from living men and women to determine proportions of Type I (slow-twitch) and II (fast-twitch) skeletal muscle fibers since the 1970s. Sex differences have been assumed but the literature has not been submitted to meta-analysis. Here, the aim was to generate effect sizes of sex differences in muscle fiber cross-sectional areas, distribution percentages, and area percentages. Data from 2875 men and 2452 women, who participated in 110 studies, were analyzed. Myofibrillar adenosine triphosphatase histochemistry was used in 71.8% of studies to classify fibers as Type I, II, IIA, and/or IIX; immunohistochemistry, immunofluorescence, or sodium dodecyl sulfate-polyacrylamide gel electrophoresis were used in 35.4% of studies to similarly classify myosin heavy chain (MHC) isoform content. Most studies involved biopsies from vastus lateralis (79.1%) in healthy individuals (92.7%) between 18 and 59 years old (80.9%). Men exhibited greater cross-sectional areas for all fiber types (g = 0.40-1.68); greater distribution percentages for Type II, MHC II, IIA, IIX fibers (g = 0.26-0.34); greater area percentages for Type II, IIA, MHC IIA, IIX fibers (g = 0.39-0.93); greater Type II/I and Type IIA/I fiber area ratios (g = 0.63, 0.94). Women exhibited greater Type I and MHC I distribution percentages (g = -0.13, -0.44); greater Type I and MHC I area percentages (g = -0.53, -0.69); greater Type I/II fiber area ratios (g = -1.24). These data, which represent the largest repository of comparative muscle fiber type data from living men and women, can inform discussions about biological sex and its impact on pathologies and sports performance (e.g., explaining sex differences in muscle strength and muscle endurance).
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Affiliation(s)
- James L Nuzzo
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, Australia
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Smith IC, Herzog W. Assumptions about the cross-sectional shape of skinned muscle fibers can distort the relationship between muscle force and cross-sectional area. J Appl Physiol (1985) 2023; 135:1036-1040. [PMID: 37732377 DOI: 10.1152/japplphysiol.00383.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Revised: 08/28/2023] [Accepted: 09/14/2023] [Indexed: 09/22/2023] Open
Abstract
Comparisons of muscle force output are often performed after normalization to muscle physiological cross-sectional area (CSA). Differences in force per CSA (i.e., specific force) suggest the presence of physiological differences in contractile function. Permeabilized mammalian skeletal muscle fibers frequently exhibit substantial declines in specific force with increasing CSA, suggesting that smaller fibers are intrinsically stronger than larger fibers of the same group. However, the potential for CSA assessment error to account for CSA-dependent differences in specific force has not received adequate attention. Assessment of fiber CSA typically involves measurement of fiber width and perhaps also height, and CSA is calculated by assuming the cross sections are either circular or elliptical with major and minor axes aligned with the optical measurement system. Differences between the assumed and real cross-sectional shapes would cause variability in the ratio of assessed CSA (aCSA) to real CSA (rCSA). This variability can insidiously bias aCSA such that large aCSAs typically overstate rCSAs of the fibers they represent, and small aCSAs typically understate the rCSAs of the fibers they represent. As aCSA is the denominator for the specific force calculation, scatterplots of specific force versus aCSA would be expected to show declines in specific force as aCSA increases without a corresponding effect in a scatterplot of specific force versus rCSA. When comparing active and passive muscle forces between data subsets defined by aCSA, the impact of CSA assessment error should be considered before exploring other physiological mechanisms.
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Affiliation(s)
- Ian C Smith
- NeuroMuscular Centre, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
| | - Walter Herzog
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Alberta, Canada
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Bersiner K, Park SY, Schaaf K, Yang WH, Theis C, Jacko D, Gehlert S. Resistance exercise: a mighty tool that adapts, destroys, rebuilds and modulates the molecular and structural environment of skeletal muscle. Phys Act Nutr 2023; 27:78-95. [PMID: 37583075 PMCID: PMC10440184 DOI: 10.20463/pan.2023.0021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 06/29/2023] [Accepted: 06/30/2023] [Indexed: 08/17/2023] Open
Abstract
PURPOSE Skeletal muscle regulates health and performance by maintaining or increasing strength and muscle mass. Although the molecular mechanisms in response to resistance exercise (RE) significantly target the activation of protein synthesis, a plethora of other mechanisms and structures must be involved in orchestrating the communication, repair, and restoration of homeostasis after RE stimulation. In practice, RE can be modulated by variations in intensity, continuity and volume, which affect molecular responses and skeletal muscle adaptation. Knowledge of these aspects is important with respect to planning of training programs and assessing the impact of RE training on skeletal muscle. METHODS In this narrative review, we introduce general aspects of skeletal muscle substructures that adapt in response to RE. We further highlighted the molecular mechanisms that control human skeletal muscle anabolism, degradation, repair and memory in response to acute and repeated RE and linked these aspects to major training variables. RESULTS Although RE is a key stimulus for the activation of skeletal muscle anabolism, it also induces myofibrillar damage. Nevertheless, to increase muscle mass accompanied by a corresponding adaptation of the essential substructures of the sarcomeric environment, RE must be continuously repeated. This requires the permanent engagement of molecular mechanisms that re-establish skeletal muscle integrity after each RE-induced muscle damage. CONCLUSION Various molecular regulators coordinately control the adaptation of skeletal muscle after acute and repeated RE and expand their actions far beyond muscle growth. Variations of key resistance training variables likely affect these mechanisms without affecting muscle growth.
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Affiliation(s)
- Käthe Bersiner
- Department for Biosciences of Sports, Institute of Sports Science, University of Hildesheim, Hildesheim, Germany
| | - So-Young Park
- Graduate School of Sports Medicine, CHA University, Pocheon, Republic of Korea
| | - Kirill Schaaf
- Department of Molecular and Cellular Sports Medicine, Institute of Cardiovascular Research and Sports Medicine, German Sport University Cologne, Cologne, Germany
| | - Woo-Hwi Yang
- Graduate School of Sports Medicine, CHA University, Pocheon, Republic of Korea
- Department of Medicine, General Graduate School, CHA University, Pocheon, Republic of Korea
| | - Christian Theis
- Center for Anaesthesiology, Helios University Hospital Wuppertal, Wuppertal, Germany
| | - Daniel Jacko
- Department of Molecular and Cellular Sports Medicine, Institute of Cardiovascular Research and Sports Medicine, German Sport University Cologne, Cologne, Germany
| | - Sebastian Gehlert
- Department for Biosciences of Sports, Institute of Sports Science, University of Hildesheim, Hildesheim, Germany
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Reece TM, Godwin JS, Strube MJ, Ciccone AB, Stout KW, Pearson JR, Vopat BG, Gallagher PM, Roberts MD, Herda TJ. Myofiber hypertrophy adaptations following 6 weeks of low-load resistance training with blood flow restriction in untrained males and females. J Appl Physiol (1985) 2023; 134:1240-1255. [PMID: 37022967 PMCID: PMC10190928 DOI: 10.1152/japplphysiol.00704.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Revised: 03/30/2023] [Accepted: 03/31/2023] [Indexed: 04/07/2023] Open
Abstract
The effects of low-load resistance training with blood flow restriction (BFR) on hypertrophy of type I/II myofibers remains unclear, especially in females. The purpose of the present study is to examine changes in type I/II myofiber cross-sectional area (fCSA) and muscle CSA (mCSA) of the vastus lateralis (VL) from before (Pre) to after (Post) 6 wk of high-load resistance training (HL; n = 15, 8 females) and low-load resistance training with BFR (n = 16, 8 females). Mixed-effects models were used to analyze fCSA with group (HL, BFR), sex (M, F), fiber type (I, II), and time (Pre, Post) included as factors. mCSA increased from pre- to posttraining (P < 0.001, d = 0.91) and was greater in males compared with females (P < 0.001, d = 2.26). Type II fCSA increased pre- to post-HL (P < 0.05, d = 0.46) and was greater in males compared with females (P < 0.05, d = 0.78). There were no significant increases in fCSA pre- to post-BFR for either fiber type or sex. Cohen's d, however, revealed moderate effect sizes in type I and II fCSA for males (d = 0.59 and 0.67), although this did not hold true for females (d = 0.29 and 0.34). Conversely, the increase in type II fCSA was greater for females than for males after HL. In conclusion, low-load resistance training with BFR may not promote myofiber hypertrophy to the level of HL resistance training, and similar responses were generally observed for males and females. In contrast, comparable effect sizes for mCSA and 1-repetition maximum (1RM) between groups suggest that BFR could play a role in a resistance training program.NEW & NOTEWORTHY This is the first study, to our knowledge, to examine myofiber hypertrophy from low-load resistance training with blood flow restriction (BFR) in females. Although this type of training did not result in myofiber hypertrophy, there were comparable increases in muscle cross-sectional area compared with high-load resistance training. These findings possibly highlight that males and females respond in a similar manner to high-load resistance training and low-load resistance training with BFR.
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Affiliation(s)
- Tanner M Reece
- Program in Physical Therapy, Washington University School of Medicine, St. Louis, Missouri, United States
| | - Joshua S Godwin
- School of Kinesiology, Auburn University, Auburn, Alabama, United States
| | - Michael J Strube
- Department of Psychological and Brain Sciences, Washington University, St. Louis, Missouri, United States
| | - Anthony B Ciccone
- Department of Exercise Science and Outdoor Recreation, Utah Valley University, Orem, Utah, United States
| | - Kevan W Stout
- Department of Health, Sport, and Exercise Sciences, University of Kansas, Lawrence, Kansas, United States
| | - Jeremy R Pearson
- Department of Health, Sport, and Exercise Sciences, University of Kansas, Lawrence, Kansas, United States
| | - Bryan G Vopat
- University of Kansas School of Medicine-Wichita, Wichita, Kansas, United States
| | - Philip M Gallagher
- Department of Health, Sport, and Exercise Sciences, University of Kansas, Lawrence, Kansas, United States
| | - Michael D Roberts
- School of Kinesiology, Auburn University, Auburn, Alabama, United States
| | - Trent J Herda
- Department of Health, Sport, and Exercise Sciences, University of Kansas, Lawrence, Kansas, United States
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Yeom S, Jeong H, Lee H, Jeon K. Effects of Lumbar Stabilization Exercises on Isokinetic Strength and Muscle Tension in Sedentary Men. Bioengineering (Basel) 2023; 10:bioengineering10030342. [PMID: 36978733 PMCID: PMC10045455 DOI: 10.3390/bioengineering10030342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 02/25/2023] [Accepted: 03/03/2023] [Indexed: 03/11/2023] Open
Abstract
Lumbar stabilization exercises (LSE) lead to high levels of erector spinae muscle (ESM) activation, which has a positive effect on improving physical function. The purpose of this study is to identify factors explaining changes in muscle strength after 7 weeks of LSE and to evaluate changes in stiffness and contraction of the ESM. All participants (male: n = 42, age = 28.26 ± 10.97) were assessed for 60°/s isokinetic extensor muscle strength and tension using a tensiomyography (TMG) and isokinetic device before and after LSE. Maximum displacement (Dm) and average velocity up to 90% Dm (Vc 90) were significantly different before and after LSE. Additionally, participants’ 60°/s isokinetic extensor strength was significantly higher after exercise. A regression analysis was conducted to test the explanatory power of the variables, and positive results were obtained in the increase in extensor strength before and after Vc 90 and LSE. Furthermore, statistical significance was set at p < 0.05. After LSE, the increase in 60°/s isokinetic extensor strength and ESM’s Dm and Vc 90 can be interpreted as positive changes post-exercise in endurance muscles with a higher percentage of type I fibers. Our results can contribute to predicting the long-term exercise effect in sedentary workers and developing an individualized strategic exercise program.
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Affiliation(s)
- Seunghyeok Yeom
- Division of Sport Science, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon 22012, Republic of Korea
- Functional Rehabilitation Biomechanics Laboratory, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon 22012, Republic of Korea
| | - Hyeongdo Jeong
- Functional Rehabilitation Biomechanics Laboratory, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon 22012, Republic of Korea
| | - Hyungwoo Lee
- Division of Sport Science, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon 22012, Republic of Korea
- Functional Rehabilitation Biomechanics Laboratory, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon 22012, Republic of Korea
- Department of Human Movement Science, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon 22012, Republic of Korea
| | - Kyoungkyu Jeon
- Division of Sport Science, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon 22012, Republic of Korea
- Functional Rehabilitation Biomechanics Laboratory, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon 22012, Republic of Korea
- Department of Human Movement Science, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon 22012, Republic of Korea
- Sport Science Institute, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon 22012, Republic of Korea
- Health Promotion Center, Incheon National University, 119 Academy-ro, Yeonsu-gu, Incheon 22012, Republic of Korea
- Correspondence: ; Tel.: +82-32-835-8578
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Mayfield DL, Cronin NJ, Lichtwark GA. Understanding altered contractile properties in advanced age: insights from a systematic muscle modelling approach. Biomech Model Mechanobiol 2023; 22:309-337. [PMID: 36335506 PMCID: PMC9958200 DOI: 10.1007/s10237-022-01651-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 10/14/2022] [Indexed: 11/09/2022]
Abstract
Age-related alterations of skeletal muscle are numerous and present inconsistently, and the effect of their interaction on contractile performance can be nonintuitive. Hill-type muscle models predict muscle force according to well-characterised contractile phenomena. Coupled with simple, yet reasonably realistic activation dynamics, such models consist of parameters that are meaningfully linked to fundamental aspects of muscle excitation and contraction. We aimed to illustrate the utility of a muscle model for elucidating relevant mechanisms and predicting changes in output by simulating the individual and combined effects on isometric force of several known ageing-related adaptations. Simulating literature-informed reductions in free Ca2+ concentration and Ca2+ sensitivity generated predictions at odds qualitatively with the characteristic slowing of contraction speed. Conversely, incorporating slower Ca2+ removal or a fractional increase in type I fibre area emulated expected changes; the former was required to simulate slowing of the twitch measured experimentally. Slower Ca2+ removal more than compensated for force loss arising from a large reduction in Ca2+ sensitivity or moderate reduction in Ca2+ release, producing realistic age-related shifts in the force-frequency relationship. Consistent with empirical data, reductions in free Ca2+ concentration and Ca2+ sensitivity reduced maximum tetanic force only slightly, even when acting in concert, suggesting a modest contribution to lower specific force. Lower tendon stiffness and slower intrinsic shortening speed slowed and prolonged force development in a compliance-dependent manner without affecting force decay. This work demonstrates the advantages of muscle modelling for exploring sources of variation and identifying mechanisms underpinning the altered contractile properties of aged muscle.
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Affiliation(s)
- Dean L Mayfield
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, Riverside, USA.
| | - Neil J Cronin
- Neuromuscular Research Centre, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland
- School of Sport and Exercise, University of Gloucestershire, Cheltenham, UK
| | - Glen A Lichtwark
- School of Human Movement and Nutrition Sciences, University of Queensland, Brisbane, Australia
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11
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Michaud F, Frey-Law LA, Lugrís U, Cuadrado L, Figueroa-Rodríguez J, Cuadrado J. Applying a muscle fatigue model when optimizing load-sharing between muscles for short-duration high-intensity exercise: A preliminary study. Front Physiol 2023; 14:1167748. [PMID: 37168228 PMCID: PMC10165736 DOI: 10.3389/fphys.2023.1167748] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 03/30/2023] [Indexed: 05/13/2023] Open
Abstract
Introduction: Multiple different mathematical models have been developed to represent muscle force, to represent multiple muscles in the musculoskeletal system, and to represent muscle fatigue. However, incorporating these different models together to describe the behavior of a high-intensity exercise has not been well described. Methods: In this work, we adapted the three-compartment controller (3CCr) muscle fatigue model to be implemented with an inverse-dynamics based optimization algorithm for the muscle recruitment problem for 7 elbow muscles to model a benchmark case: elbow flexion/extension moments. We highlight the difficulties in achieving an accurate subject-specific approach for this multi-level modeling problem, considering different muscular models, compared with experimental measurements. Both an isometric effort and a dynamic bicep curl were considered, where muscle activity and resting periods were simulated to obtain the fatigue behavior. Muscle parameter correction, scaling and calibration are addressed in this study. Moreover, fiber-type recruitment hierarchy in force generation was added to the optimization problem, thus offering an additional novel muscle modeling criterion. Results: It was observed that: i) the results were most accurate for the static case; ii) insufficient torque was predicted by the model at some time points for the dynamic case, which benefitted from a more precise calibration of muscle parameters; iii) modeling the effects of muscular potentiation may be important; and iv) for this multilevel model approach, the 3CCr model had to be modified to avoid reaching situations of unrealistic constant fatigue in high intensity exercise-resting cycles. Discussion: All the methods yield reasonable estimations, but the complexity of obtaining accurate subject-specific human models is highlighted in this study. The proposed novel muscle modeling and force recruitment criterion, which consider the muscular fiber-type distinction, show interesting preliminary results.
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Affiliation(s)
- Florian Michaud
- Laboratory of Mechanical Engineering, Campus Industrial de Ferrol, Universidade da Coruña, Ferrol, Spain
- *Correspondence: Florian Michaud,
| | - Laura A. Frey-Law
- Department of Physical Therapy and Rehabilitation Science, University of Iowa, Iowa City, IA, United Sates
| | - Urbano Lugrís
- Laboratory of Mechanical Engineering, Campus Industrial de Ferrol, Universidade da Coruña, Ferrol, Spain
| | - Lucía Cuadrado
- Department of Physical Medicine and Rehabilitation, University Hospital Complex, Santiago de Compostela, Spain
| | - Jesús Figueroa-Rodríguez
- Department of Physical Medicine and Rehabilitation, University Hospital Complex, Santiago de Compostela, Spain
| | - Javier Cuadrado
- Laboratory of Mechanical Engineering, Campus Industrial de Ferrol, Universidade da Coruña, Ferrol, Spain
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12
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Factors of Muscle Quality and Determinants of Muscle Strength: A Systematic Literature Review. Healthcare (Basel) 2022; 10:healthcare10101937. [PMID: 36292384 PMCID: PMC9601777 DOI: 10.3390/healthcare10101937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 09/14/2022] [Accepted: 09/26/2022] [Indexed: 11/04/2022] Open
Abstract
Muscle quality defined as the ratio of muscle strength to muscle mass disregards underlying factors which influence muscle strength. The aim of this review was to investigate the relationship of phase angle (PhA), echo intensity (EI), muscular adipose tissue (MAT), muscle fiber type, fascicle pennation angle (θf), fascicle length (lf), muscle oxidative capacity, insulin sensitivity (IS), neuromuscular activation, and motor unit to muscle strength. PubMed search was performed in 2021. The inclusion criteria were: (i) original research, (ii) human participants, (iii) adults (≥18 years). Exclusion criteria were: (i) no full-text, (ii) non-English or -German language, (iii) pathologies. Forty-one studies were identified. Nine studies found a weak−moderate negative (range r: [−0.26]−[−0.656], p < 0.05) correlation between muscle strength and EI. Four studies found a weak−moderate positive correlation (range r: 0.177−0.696, p < 0.05) between muscle strength and PhA. Two studies found a moderate-strong negative correlation (range r: [−0.446]−[−0.87], p < 0.05) between muscle strength and MAT. Two studies found a weak-strong positive correlation (range r: 0.28−0.907, p < 0.05) between θf and muscle strength. Muscle oxidative capacity was found to be a predictor of muscle strength. This review highlights that the current definition of muscle quality should be expanded upon as to encompass all possible factors of muscle quality.
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13
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The Effects of Different Relative Loads in Weight Training on Acceleration and Acceleration from Flying Starts. Sports (Basel) 2022; 10:sports10100148. [PMID: 36287761 PMCID: PMC9611022 DOI: 10.3390/sports10100148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 09/20/2022] [Accepted: 09/22/2022] [Indexed: 11/17/2022] Open
Abstract
The purpose of this review was to examine how different relative loads in weight training can improve acceleration over 10 m from a standing or flying start. A systematic review of the literature was undertaken using the following databases: PubMed, MedLine, Google Scholar, and SPORTDiscus. Studies were eligible if they met the following criteria: (1) participants were at least 15 years or older and healthy and injury free, (2) the study included at least one exercise for the lower body with a strength training frequency of at least once a week and included a training period of at least four weeks, and (3) interventions with clear pre- and post-test results on 10 m sprint or 10 m flying start are stated. Non-English-language articles were excluded. Percent change and between-group effect size (ES) were calculated to compare the effects of different training interventions. Forty-nine studies met the inclusion criteria. The results were categorized into four groups: (1) explosive weight training with light loads at 30–60% of 1-RM, (2) explosive weight training with moderate loads at 60–85% of 1-RM, (3) maximal weight training at 85–100% of 1-RM, and (4) hypertrophy training at 60–85% of 1-RM. At 10 m, all methods of weight training demonstrated improvements, and maximal weight training demonstrated the highest results with a large ES, while other approaches varied from very small to moderate ES. Weight training showed little progression with a significantly lower effect on flying start across all training methods, except for one group that trained power cleans (hypertrophy) where progress was large. To improve acceleration over the first 10 m, this review demonstrated maximal weight training as the preferred training method. For athletes with a pre-existing high level of strength, it could be more appropriate to use explosive training with light loads or a combination of the two. To a lesser extent, acceleration from a flying start could be improved using both training methods as well.
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14
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Resistance exercise training and the motor unit. Eur J Appl Physiol 2022; 122:2019-2035. [PMID: 35751668 DOI: 10.1007/s00421-022-04983-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 06/06/2022] [Indexed: 11/03/2022]
Abstract
Resistance exercise training (RET) is a key modality to enhance sports performance, injury prevention and rehabilitation, and improving overall health via increases in muscular strength. Yet, the contribution of neural mechanisms to increases in muscular strength are highly debated. This is particularly true for the involvement of the motor unit, which is the link between neural (activation) and mechanical (muscle fiber twitch forces) mechanisms. A plethora of literature that examines the effects of RET on skeletal muscle speculate the role of motor units, such as increases in firing rates partially explains muscular strength gains. Results, however, are mixed regarding changes in firing rates in studies that utilize single motor unit recordings. The lack of clarity could be related to vast or subtle differences in RET programs, methods to record motor units, muscles tested, types of contractions and intensities used to record motor units, etc. Yet to be discussed, mixed findings could be the result of non-uniform MU behavior that is not typically accounted for in RET research. The purpose of this narration is to discuss the effects of acute resistance exercise training studies on MU behavior and to provide guidance for future research.
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15
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Guan Y, Yan Z. Molecular Mechanisms of Exercise and Healthspan. Cells 2022; 11:872. [PMID: 35269492 PMCID: PMC8909156 DOI: 10.3390/cells11050872] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 02/25/2022] [Accepted: 02/26/2022] [Indexed: 12/16/2022] Open
Abstract
Healthspan is the period of our life without major debilitating diseases. In the modern world where unhealthy lifestyle choices and chronic diseases taper the healthspan, which lead to an enormous economic burden, finding ways to promote healthspan becomes a pressing goal of the scientific community. Exercise, one of humanity's most ancient and effective lifestyle interventions, appears to be at the center of the solution since it can both treat and prevent the occurrence of many chronic diseases. Here, we will review the current evidence and opinions about regular exercise promoting healthspan through enhancing the functionality of our organ systems and preventing diseases.
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Affiliation(s)
- Yuntian Guan
- Department of Pharmacology, School of Medicine, University of Virginia, Charlottesville, VA 22903, USA;
- Center for Skeletal Muscle Research at the Robert M. Berne Cardiovascular Research Center, School of Medicine, University of Virginia, Charlottesville, VA 22903, USA
| | - Zhen Yan
- Department of Pharmacology, School of Medicine, University of Virginia, Charlottesville, VA 22903, USA;
- Center for Skeletal Muscle Research at the Robert M. Berne Cardiovascular Research Center, School of Medicine, University of Virginia, Charlottesville, VA 22903, USA
- Department of Medicine, School of Medicine, University of Virginia, Charlottesville, VA 22903, USA
- Department of Molecular Physiology and Biological Biophysics, School of Medicine, University of Virginia, Charlottesville, VA 22903, USA
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16
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Takaragawa M, Tobina T, Shiose K, Kakigi R, Tsuzuki T, Ichinoseki-Sekine N, Kumagai H, Zempo H, Miyamoto-Mikami E, Kobayashi H, Naito H, Fuku N. Genotype Score for Iron Status Is Associated with Muscle Fiber Composition in Women. Genes (Basel) 2021; 13:genes13010005. [PMID: 35052344 PMCID: PMC8775127 DOI: 10.3390/genes13010005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 12/16/2021] [Accepted: 12/17/2021] [Indexed: 01/01/2023] Open
Abstract
Human muscle fiber composition is heterogeneous and mainly determined by genetic factors. A previous study reported that experimentally induced iron deficiency in rats increases the proportion of fast-twitch muscle fibers. Iron status has been reported to be affected by genetic factors. As the TMPRSS6 rs855791 T/C and HFE rs1799945 C/G polymorphisms are strongly associated with iron status in humans, we hypothesized that the genotype score (GS) based on these polymorphisms could be associated with the muscle fiber composition in humans. Herein, we examined 214 Japanese individuals, comprising of 107 men and 107 women, for possible associations of the GS for iron status with the proportion of myosin heavy chain (MHC) isoforms (I, IIa, and IIx) as markers of muscle fiber composition. No statistically significant correlations were found between the GS for iron status and the proportion of MHC isoforms in all participants. When the participants were stratified based on sex, women showed positive and negative correlations of the GS with MHC-IIa (age-adjusted p = 0.020) and MHC-IIx (age-adjusted p = 0.011), respectively. In contrast, no correlation was found in men. In women, a 1-point increase in the GS was associated with 2.42% higher MHC-IIa level and 2.72% lower MHC-IIx level. Our results suggest that the GS based on the TMPRSS6 rs855791 T/C and HFE rs1799945 C/G polymorphisms for iron status is associated with muscle fiber composition in women.
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Affiliation(s)
- Mizuki Takaragawa
- Graduate School of Health and Sports Science, Juntendo University, Chiba 270-1695, Japan; (M.T.); (N.I.-S.); (H.K.); (E.M.-M.); (H.K.); (H.N.)
| | - Takuro Tobina
- Faculty of Nursing and Nutrition, University of Nagasaki, Nagasaki 851-2195, Japan;
| | - Keisuke Shiose
- Faculty of Education, University of Miyazaki, Miyazaki 889-2192, Japan;
| | - Ryo Kakigi
- Faculty of Management & Information Science, Josai International University, Chiba 283-8555, Japan;
| | | | - Noriko Ichinoseki-Sekine
- Graduate School of Health and Sports Science, Juntendo University, Chiba 270-1695, Japan; (M.T.); (N.I.-S.); (H.K.); (E.M.-M.); (H.K.); (H.N.)
- Faculty of Liberal Arts, The Open University of Japan, Chiba 261-8586, Japan
| | - Hiroshi Kumagai
- Graduate School of Health and Sports Science, Juntendo University, Chiba 270-1695, Japan; (M.T.); (N.I.-S.); (H.K.); (E.M.-M.); (H.K.); (H.N.)
| | - Hirofumi Zempo
- Faculty of Health and Nutrition, Tokyo Seiei College, Tokyo 124-8530, Japan;
| | - Eri Miyamoto-Mikami
- Graduate School of Health and Sports Science, Juntendo University, Chiba 270-1695, Japan; (M.T.); (N.I.-S.); (H.K.); (E.M.-M.); (H.K.); (H.N.)
| | - Hiroyuki Kobayashi
- Graduate School of Health and Sports Science, Juntendo University, Chiba 270-1695, Japan; (M.T.); (N.I.-S.); (H.K.); (E.M.-M.); (H.K.); (H.N.)
- Mito Medical Center, Tsukuba University Hospital, Ibaraki 310-0015, Japan
| | - Hisashi Naito
- Graduate School of Health and Sports Science, Juntendo University, Chiba 270-1695, Japan; (M.T.); (N.I.-S.); (H.K.); (E.M.-M.); (H.K.); (H.N.)
| | - Noriyuki Fuku
- Graduate School of Health and Sports Science, Juntendo University, Chiba 270-1695, Japan; (M.T.); (N.I.-S.); (H.K.); (E.M.-M.); (H.K.); (H.N.)
- Correspondence: ; Tel.: +81-476-98-1001 (ext. 9203)
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17
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Chen M, Zhou L, Chen S, Shangguan R, Qu Y, Sun J. Acute and chronic effects of high-intensity interval training (HIIT) on postexercise intramuscular lipid metabolism in rats. Physiol Res 2021; 70:735-743. [PMID: 34505529 DOI: 10.33549/physiolres.934722] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Recovery from exercise refers to the period between the end of a bout of exercise and the subsequent return to a resting or recovered state. It is a dynamic period in which many physiological changes occur. A large amount of research has evaluated the effect of training on intramuscular lipid metabolism. However, data are limited regarding intramuscular lipid metabolism during the recovery period. In this study, lipid metabolism-related proteins were examined after a single bout of exercise in a time-dependent way to explore the mechanism of how exercise induces intramuscular lipid metabolism adaptation. Firstly, all rats in the exercise group underwent a five-week training protocol (HIIT, five times/week), and then performed a more intense HIIT session after 72 h of the last-time five-week training. After that, rats were sampled in a time-dependent way, including 0 h, 6 h, 12 h, 24 h, 48 h, 72 h, and 96 h following the acute training session. Our results discovered that five weeks of HIIT increased the content of intramuscular triglyceride (IMTG) and enhanced the lipolytic and lipogenesis-related proteins in skeletal muscle. Furthermore, IMTG content decreased immediately post HIIT and gradually increased to baseline levels 48 h postexercise, continuing to over-recover up to 96 h postexercise. Following acute exercise, lipolytic-related proteins showed an initial increase (6-12 h) before decreasing during recovery. Conversely, lipogenesis-related proteins decreased following exercise (6-12 h), then increased in the recovery period. Based on the changes, we speculate that skeletal muscle is predominated by lipid oxidative at the first 12 h postexercise. After this period, lipid synthesis-related proteins increased, which may be the result of body recovery. Together, these results may provide insight into how the lipid metabolism-related signaling changes after chronic and acute HIIT and how protein levels lipid metabolism correlates to IMTG recovery.
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Affiliation(s)
- M Chen
- Institute of Sports Science, Sichuan University, Chengdu, People's Republic of China.
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18
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Kalakoutis M, Di Giulio I, Douiri A, Ochala J, Harridge SDR, Woledge RC. Methodological considerations in measuring specific force in human single skinned muscle fibres. Acta Physiol (Oxf) 2021; 233:e13719. [PMID: 34286921 DOI: 10.1111/apha.13719] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 07/14/2021] [Accepted: 07/15/2021] [Indexed: 02/02/2023]
Abstract
Chemically skinned fibres allow the study of human muscle contractile function in vitro. A particularly important parameter is specific force (SF), that is, maximal isometric force divided by cross-sectional area, representing contractile quality. Although SF varies substantially between studies, the magnitude and cause of this variability remains puzzling. Here, we aimed to summarize and explore the cause of variability in SF between studies. A systematic search was conducted in Medline, Embase and Web of Science databases in June 2020, yielding 137 data sets from 61 publications which studied healthy, young adults. Five-fold differences in mean SF data were observed. Adjustments to the reported data for key methodological differences allowed between-study comparisons to be made. However, adjustment for fibre shape, swelling and sarcomere length failed to significantly reduce SF variance (I2 = 96%). Interestingly, grouping papers based on shared authorship did reveal consistency within research groups. In addition, lower SF was found to be associated with higher phosphocreatine concentrations in the fibre activating solution and with Triton X-100 being used as a skinning agent. Although the analysis showed variance across the literature, the ratio of SF in single fibres containing myosin heavy chain isoforms IIA or I was found to be consistent across research groups. In conclusion, whilst the skinned fibre technique is reliable for studying in vitro force generation of single fibres, the composition of the solution used to activate fibres, which differs between research groups, is likely to heavily influence SF values.
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Affiliation(s)
- Michaeljohn Kalakoutis
- Centre for Human and Applied Physiological Sciences Faculty of Life Sciences & Medicine King’s College London London UK
| | - Irene Di Giulio
- Centre for Human and Applied Physiological Sciences Faculty of Life Sciences & Medicine King’s College London London UK
| | - Abdel Douiri
- School of Population Health and Environmental Sciences King’s College London London UK
| | - Julien Ochala
- Centre for Human and Applied Physiological Sciences Faculty of Life Sciences & Medicine King’s College London London UK
- Department of Biomedical Sciences Faculty of Health and Medical Sciences University of Copenhagen Copenhagen Denmark
| | - Stephen D. R. Harridge
- Centre for Human and Applied Physiological Sciences Faculty of Life Sciences & Medicine King’s College London London UK
| | - Roger C. Woledge
- Centre for Human and Applied Physiological Sciences Faculty of Life Sciences & Medicine King’s College London London UK
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19
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Folland JP, Balshaw TG. Muscle Growth Does Contribute to the Increases in Strength that Occur after Resistance Training. Med Sci Sports Exerc 2021; 53:2006-2010. [PMID: 34398063 DOI: 10.1249/mss.0000000000002732] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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20
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Maximal muscular power: lessons from sprint cycling. SPORTS MEDICINE-OPEN 2021; 7:48. [PMID: 34268627 PMCID: PMC8282832 DOI: 10.1186/s40798-021-00341-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 06/29/2021] [Indexed: 02/07/2023]
Abstract
Maximal muscular power production is of fundamental importance to human functional capacity and feats of performance. Here, we present a synthesis of literature pertaining to physiological systems that limit maximal muscular power during cyclic actions characteristic of locomotor behaviours, and how they adapt to training. Maximal, cyclic muscular power is known to be the main determinant of sprint cycling performance, and therefore we present this synthesis in the context of sprint cycling. Cyclical power is interactively constrained by force-velocity properties (i.e. maximum force and maximum shortening velocity), activation-relaxation kinetics and muscle coordination across the continuum of cycle frequencies, with the relative influence of each factor being frequency dependent. Muscle cross-sectional area and fibre composition appear to be the most prominent properties influencing maximal muscular power and the power-frequency relationship. Due to the role of muscle fibre composition in determining maximum shortening velocity and activation-relaxation kinetics, it remains unclear how improvable these properties are with training. Increases in maximal muscular power may therefore arise primarily from improvements in maximum force production and neuromuscular coordination via appropriate training. Because maximal efforts may need to be sustained for ~15-60 s within sprint cycling competition, the ability to attenuate fatigue-related power loss is also critical to performance. Within this context, the fatigued state is characterised by impairments in force-velocity properties and activation-relaxation kinetics. A suppression and leftward shift of the power-frequency relationship is subsequently observed. It is not clear if rates of power loss can be improved with training, even in the presence adaptations associated with fatigue-resistance. Increasing maximum power may be most efficacious for improving sustained power during brief maximal efforts, although the inclusion of sprint interval training likely remains beneficial. Therefore, evidence from sprint cycling indicates that brief maximal muscular power production under cyclical conditions can be readily improved via appropriate training, with direct implications for sprint cycling as well as other athletic and health-related pursuits.
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21
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Gejl KD, Hvid LG, Andersson EP, Jensen R, Holmberg HC, Ørtenblad N. Contractile Properties of MHC I and II Fibers From Highly Trained Arm and Leg Muscles of Cross-Country Skiers. Front Physiol 2021; 12:682943. [PMID: 34220547 PMCID: PMC8242206 DOI: 10.3389/fphys.2021.682943] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 05/18/2021] [Indexed: 11/13/2022] Open
Abstract
Introduction Little is known about potential differences in contractile properties of muscle fibers of the same type in arms and legs. Accordingly, the present study was designed to compare the force-generating capacity and Ca2+ sensitivity of fibers from arm and leg muscles of highly trained cross-country skiers. Method Single muscle fibers of m. vastus lateralis and m. triceps brachii of eight highly trained cross-country skiers were analyzed with respect to maximal Ca2+-activated force, specific force and Ca2+ sensitivity. Result The maximal Ca2+-activated force was greater for myosin heavy chain (MHC) II than MHC I fibers in both the arm (+62%, P < 0.001) and leg muscle (+77%, P < 0.001), with no differences between limbs for each MHC isoform. In addition, the specific force of MHC II fibers was higher than that of MHC I fibers in both arms (+41%, P = 0.002) and legs (+95%, P < 0.001). The specific force of MHC II fibers was the same in both limbs, whereas MHC I fibers from the m. triceps brachii were, on average, 39% stronger than fibers of the same type from the m. vastus lateralis (P = 0.003). pCa50 was not different between MHC I and II fibers in neither arms nor legs, but the MHC I fibers of m. triceps brachii demonstrated higher Ca2+ sensitivity than fibers of the same type from m. vastus lateralis (P = 0.007). Conclusion Comparison of muscles in limbs equally well trained revealed that MHC I fibers in the arm muscle exhibited a higher specific force-generating capacity and greater Ca2+ sensitivity than the same type of fiber in the leg, with no such difference in the case of MHC II fibers. These distinct differences in the properties of fibers of the same type in equally well-trained muscles open new perspectives in muscle physiology.
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Affiliation(s)
- Kasper Degn Gejl
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Lars G Hvid
- Department of Public Health, Exercise Biology, Aarhus University, Aarhus, Denmark
| | - Erik P Andersson
- Swedish Winter Sports Research Centre, Department of Health Sciences, Mid Sweden University, Östersund, Sweden.,School of Sport Sciences, Faculty of Health Sciences, UiT The Arctic University of Norway, Tromsö, Norway
| | - Rasmus Jensen
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
| | - Hans-Christer Holmberg
- Swedish Winter Sports Research Centre, Department of Health Sciences, Mid Sweden University, Östersund, Sweden.,Department of Health Sciences, Luleå University of Technology, Luleå, Sweden.,Department of Physiology and Pharmacology, Karolinska Institute, Stockholm, Sweden
| | - Niels Ørtenblad
- Department of Sports Science and Clinical Biomechanics, University of Southern Denmark, Odense, Denmark
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22
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Watanabe K, Holobar A, Uchida K, Mita Y. Fish Protein Ingestion Induces Neural, but Not Muscular Adaptations, Following Resistance Training in Young Adults. Front Nutr 2021; 8:645747. [PMID: 33777994 PMCID: PMC7993090 DOI: 10.3389/fnut.2021.645747] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 02/18/2021] [Indexed: 11/13/2022] Open
Abstract
Purpose: Nutritional supplementation in conjunction with exercise is of interest for the prevention or improvement of declines in motor performances in older adults. An understanding of the effects on both young and older adults contributes to its effective application. We investigated the effect of fish protein ingestion with resistance training on neural and muscular adaptations in young adults using interventions and assessments that have already been tested in older adults. Methods: Eighteen young adults underwent 8 weeks of isometric knee extension training. During the intervention, nine participants ingested 5 g of fish protein (n = 9, Alaska pollack protein, APP), and the other nine participants ingested casein as a control (n = 9, CAS) in addition to daily meals. Before, during, and after the intervention, the isometric knee extension force, lower extremity muscle mass, and motor unit firing pattern of knee extensor muscles were measured. Results: Maximum voluntary contraction (MVC) was significantly increased in both APP and CAS groups from 0 weeks to 4, 6, and 8 weeks of intervention (p < 0.001), but there were no significant differences between the groups (p = 0.546–0.931). Muscle mass was not significantly changed during the intervention in either group (p = 0.250–0.698). Significant changes in motor unit firing rates (p = 0.02 and 0.029 for motor units recruited at 20–40% of MVC and at 40–60%) were observed following the intervention in the APP but not CAS (p = 0.120–0.751) group. Conclusions: These results suggest that dietary fish protein ingestion changes motor unit adaptations following resistance training in young adults.
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Affiliation(s)
- Kohei Watanabe
- Laboratory of Neuromuscular Biomechanics, Faculty of Liberal Arts and Sciences and School of International Liberal Studies, Chukyo University, Nagoya, Japan
| | - Aleš Holobar
- Faculty of Electrical Engineering and Computer Science, University of Maribor, Maribor, Slovenia
| | | | - Yukiko Mita
- Department of Human Nutrition, School of Life Studies, Sugiyama Jogakuen University, Nagoya, Japan
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23
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Monti E, Toniolo L, Marcucci L, Bondì M, Martellato I, Šimunič B, Toninello P, Franchi MV, Narici MV, Reggiani C. Are muscle fibres of body builders intrinsically weaker? A comparison with single fibres of aged-matched controls. Acta Physiol (Oxf) 2021; 231:e13557. [PMID: 32921001 DOI: 10.1111/apha.13557] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 08/21/2020] [Accepted: 09/03/2020] [Indexed: 12/17/2022]
Abstract
AIM Skeletal muscles of Body Builders (BB) represent an interesting model to study muscle mass gains in response to high volume resistance training. It is debated whether muscle contractile performance improves in proportion to mass. Here, we aim to assess whether muscle hypertrophy does not occur at the expense of performance. METHODS Six BB and Six untrained controls (CTRL) were recruited. Cross-sectional area (CSA) and maximum voluntary contraction (MVC) of quadriceps femoris muscle (QF) and CSA and architecture of vastus lateralis (VL) were determined. Moreover, a biopsy was taken from VL mid-portion and single fibres were analysed. RESULTS QF CSA and MVC were 32% (n.s., P = .052) and 58% (P = .009) higher in BB than in CTRL, respectively. VL CSA was 37% higher in BB (P = .030). Fast 2A fibres CSA was 24% (P = .048) greater in BB than in CTRL, when determined in immunostained sections of biopsy samples. Single permeabilized fast fibres CSA was 37% (n.s., P = .052) higher in BB than in CTRL, and their force was slightly higher in BB (n.s.), while specific tension (P0 ) was 19% (P = .024) lower. The lower P0 was not explained either by lower myosin content or by impaired calcium diffusion. Conversely, the swelling caused by skinning-induced permeabilization was different and, when used to correct P0 , differences between populations disappeared. CONCLUSIONS The results show that high degree of muscle hypertrophy is not detrimental for force generation capacity, as increases in fibre size and force are strictly proportional once the differential swelling response is accounted for.
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Affiliation(s)
- Elena Monti
- Department of Biomedical Sciences University of Padova Padova Italy
| | - Luana Toniolo
- Department of Biomedical Sciences University of Padova Padova Italy
| | - Lorenzo Marcucci
- Department of Biomedical Sciences University of Padova Padova Italy
| | - Michela Bondì
- Department of Biomedical Sciences University of Padova Padova Italy
| | - Ivan Martellato
- Department of Biomedical Sciences University of Padova Padova Italy
| | - Bostjan Šimunič
- Science and Research Centre Koper Institute for Kinesiology Research Koper Slovenia
| | - Paolo Toninello
- Clinic of Plastic Surgery Padova University Hospital Padova Italy
| | | | - Marco V. Narici
- Department of Biomedical Sciences University of Padova Padova Italy
- Science and Research Centre Koper Institute for Kinesiology Research Koper Slovenia
- CIR‐MYO Myology Centre Department of Biomedical Sciences University of Padua Padova Italy
| | - Carlo Reggiani
- Department of Biomedical Sciences University of Padova Padova Italy
- Science and Research Centre Koper Institute for Kinesiology Research Koper Slovenia
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Emphasizing Task-Specific Hypertrophy to Enhance Sequential Strength and Power Performance. J Funct Morphol Kinesiol 2020; 5:jfmk5040076. [PMID: 33467291 PMCID: PMC7739346 DOI: 10.3390/jfmk5040076] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 10/04/2020] [Accepted: 10/21/2020] [Indexed: 12/15/2022] Open
Abstract
While strength is indeed a skill, most discussions have primarily considered structural adaptations rather than ultrastructural augmentation to improve performance. Altering the structural component of the muscle is often the aim of hypertrophic training, yet not all hypertrophy is equal; such alterations are dependent upon how the muscle adapts to the training stimuli and overall training stress. When comparing bodybuilders to strength and power athletes such as powerlifters, weightlifters, and throwers, while muscle size may be similar, the ability to produce force and power is often inequivalent. Thus, performance differences go beyond structural changes and may be due to the muscle's ultrastructural constituents and training induced adaptations. Relative to potentiating strength and power performances, eliciting specific ultrastructural changes should be a variable of interest during hypertrophic training phases. By focusing on task-specific hypertrophy, it may be possible to achieve an optimal amount of hypertrophy while deemphasizing metabolic and aerobic components that are often associated with high-volume training. Therefore, the purpose of this article is to briefly address different types of hypertrophy and provide directions for practitioners who are aiming to achieve optimal rather than maximal hypertrophy, as it relates to altering ultrastructural muscular components, to potentiate strength and power performance.
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25
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Reggiani C, Schiaffino S. Muscle hypertrophy and muscle strength: dependent or independent variables? A provocative review. Eur J Transl Myol 2020; 30:9311. [PMID: 33117512 PMCID: PMC7582410 DOI: 10.4081/ejtm.2020.9311] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 08/23/2020] [Indexed: 01/02/2023] Open
Abstract
The question whether the muscle hypertrophy induced by resistance training, hormone administration or genetic manipulation is accompanied by a proportional increase in muscle strength is still open. This review summarizes and analyses data obtained in human and rodent muscles in studies that have monitored in parallel changes in muscle size and changes in muscle force, measured in isometric contractions in vivo, in isolated muscles ex vivo (in rodents) and in single muscle fibers. Although a general positive relation exists among the two variables, a number of studies show a clear dissociation with increase of muscle size with no change or even decrease in strength and, vice versa, increase in strength without increase in size. The possible mechanisms of such dissociation, which involves neural motor control and/or cellular and molecular adaptations of muscle fibers, are briefly discussed.
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Affiliation(s)
- Carlo Reggiani
- Department of Biomedical Sciences of the University of Padova, Padova, Italy.,Science and Research Centre Koper, Institute for Kinesiology Research, Koper, Slovenia
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26
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Yvert T, Miyamoto-Mikami E, Tobina T, Shiose K, Kakigi R, Tsuzuki T, Takaragawa M, Ichinoseki-Sekine N, Pérez M, Kobayashi H, Tanaka H, Naito H, Fuku N. PPARGC1A rs8192678 and NRF1 rs6949152 Polymorphisms Are Associated with Muscle Fiber Composition in Women. Genes (Basel) 2020; 11:genes11091012. [PMID: 32867330 PMCID: PMC7563119 DOI: 10.3390/genes11091012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 08/20/2020] [Accepted: 08/25/2020] [Indexed: 02/07/2023] Open
Abstract
PPARGC1A rs8192678 G/A (Gly482Ser) and NRF1 rs6949152 A/G polymorphisms have been associated with endurance athlete status, endurance performance phenotypes, and certain health-related markers of different pathologies such as metabolic syndrome, diabetes, and dyslipidemia. We hypothesized that they could be considered interesting candidates for explaining inter-individual variations in muscle fiber composition in humans. We aimed to examine possible associations of these polymorphisms with myosin heavy-chain (MHC) isoforms as markers of muscle fiber compositions in vastus lateralis muscle in a population of 214 healthy Japanese subjects, aged between 19 and 79 years. No significant associations were found in men for any measured variables. In contrast, in women, the PPARGC1A rs8192678 A/A genotype was significantly associated with a higher proportion of MHC-I (p = 0.042) and with a lower proportion of MHC-IIx (p = 0.033), and the NRF1 rs6949152 AA genotype was significantly associated with a higher proportion of MHC-I (p = 0.008) and with a lower proportion of MHC IIx (p = 0.035). In women, the genotype scores of the modes presenting the most significant results for PPARGC1A rs8192678 G/A (Gly482Ser) and NRF1 rs6949152 A/G polymorphisms were significantly associated with MHC-I (p = 0.0007) and MHC IIx (p = 0.0016). That is, women with combined PPARGC1A A/A and NRF1 A/A genotypes presented the highest proportion of MHC-I and the lowest proportion of MHC-IIx, in contrast to women with combined PPARGC1A GG+GA and NRF1 AG+GG genotypes, who presented the lowest proportion of MHC-I and the highest proportion of MHC-IIx. Our results suggest possible associations between these polymorphisms (both individually and in combination) and the inter-individual variability observed in muscle fiber composition in women, but not in men.
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Affiliation(s)
- Thomas Yvert
- Graduate School of Health and Sports Science, Juntendo University, Chiba 270-1695, Japan; (T.Y.); (E.M.-M.); (M.T.); (N.I.-S.); (H.N.)
- Faculty of Sport Sciences, Universidad Europea de Madrid, 28670 Madrid, Spain;
| | - Eri Miyamoto-Mikami
- Graduate School of Health and Sports Science, Juntendo University, Chiba 270-1695, Japan; (T.Y.); (E.M.-M.); (M.T.); (N.I.-S.); (H.N.)
| | - Takuro Tobina
- Faculty of Nursing and Nutrition, University of Nagasaki, Nagasaki 851-2195, Japan;
| | - Keisuke Shiose
- Faculty of Education, University of Miyazaki, Miyazaki 889-2192, Japan;
| | - Ryo Kakigi
- Faculty of Management & Information Science, Josai International University, Chiba 283-8555, Japan;
| | | | - Mizuki Takaragawa
- Graduate School of Health and Sports Science, Juntendo University, Chiba 270-1695, Japan; (T.Y.); (E.M.-M.); (M.T.); (N.I.-S.); (H.N.)
| | - Noriko Ichinoseki-Sekine
- Graduate School of Health and Sports Science, Juntendo University, Chiba 270-1695, Japan; (T.Y.); (E.M.-M.); (M.T.); (N.I.-S.); (H.N.)
- Faculty of Liberal Arts, The Open University of Japan, Chiba 261-8586, Japan
| | - Margarita Pérez
- Faculty of Sport Sciences, Universidad Europea de Madrid, 28670 Madrid, Spain;
| | - Hiroyuki Kobayashi
- Department of General Medicine, Mito Medical Center, Tsukuba University Hospital, Ibaraki 310-0015, Japan;
| | - Hiroaki Tanaka
- Faculty of Sports and Health Science, Fukuoka University, Fukuoka 814-0180, Japan
| | - Hisashi Naito
- Graduate School of Health and Sports Science, Juntendo University, Chiba 270-1695, Japan; (T.Y.); (E.M.-M.); (M.T.); (N.I.-S.); (H.N.)
| | - Noriyuki Fuku
- Graduate School of Health and Sports Science, Juntendo University, Chiba 270-1695, Japan; (T.Y.); (E.M.-M.); (M.T.); (N.I.-S.); (H.N.)
- Correspondence: ; Tel.: +81-476-98-1001 (ext. 9203)
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27
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Shoepe TC, McCormack WP, LaBrie JW, Mello GT, Almstedt HC. Indicators of Sarcopenia: Sex Differences in Competitive Runners Prior to Peak Muscle Mass. Int J Sports Med 2020; 41:1067-1076. [PMID: 32722828 DOI: 10.1055/a-1202-1663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Strength, muscle mass, and muscle quality have been observed to be compromised in low body-mass index individuals such as competitive runners, increasing their risk for sarcopenia. The purpose was to compare indices of sarcopenia in young runners to age, height, body-mass, and body-mass index-matched non-runners. Handgrip strength and arm composition from dual-energy x-ray absorptiometry (baseline-T1, T2=5.3±1.4, T3=11.5±0.7 months later) were assessed in 40 non-runners and 40 runners (19.3±0.7 vs. 19.2±1.1 years, 170.7±10.3 vs. 171.1±9.1 cm, 60.2±7.4 vs. 60.2±7.9 kg, 20.6±0.9 vs. 20.5±1.5 kg m-2). The unitless variable of muscle quality, was defined as the sum of right and left maximal handgrip (in kg) divided by the sum of bone-free lean mass of both arms (in kg). Female runners displayed the highest muscle quality (T1=15.3±1.7; T3=15.7±2.0) compared to male runners (T1=13.7±1.4, p < 0.001; T3=14.2±1.6, p < 0.001) and male non-runners (T1=12.4±1.8, p=0.001; T3=13.2±1.6, p < 0.001), while female non-runners (T1=14.6±2.5, p=0.154; T3=15.1 ±2.2, p=0.124) showed higher muscle quality than male non-runners. Higher muscle quality in low-body-mass index females persists over one-year during young-adulthood and while running contributes to whole-body muscle mass accrual, it does not appear to be significantly associated with improvements in the most commonly used upper-body diagnostic indicator of sarcopenia.
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Affiliation(s)
- Todd C Shoepe
- Health and Human Sciences, Loyola Marymount University Frank R Seaver College of Science and Engineering, Los Angeles, United States
| | - William P McCormack
- Health and Human Sciences, Loyola Marymount University Frank R Seaver College of Science and Engineering, Los Angeles, United States
| | - Joseph W LaBrie
- Health and Human Sciences, Loyola Marymount University, Los Angeles, United States
| | - Grant T Mello
- Health and Human Sciences, Loyola Marymount University Frank R Seaver College of Science and Engineering, Los Angeles, United States
| | - Hawley C Almstedt
- Health and Human Sciences, Loyola Marymount University Frank R Seaver College of Science and Engineering, Los Angeles, United States
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28
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Roberts MD, Haun CT, Vann CG, Osburn SC, Young KC. Sarcoplasmic Hypertrophy in Skeletal Muscle: A Scientific "Unicorn" or Resistance Training Adaptation? Front Physiol 2020; 11:816. [PMID: 32760293 PMCID: PMC7372125 DOI: 10.3389/fphys.2020.00816] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 06/18/2020] [Indexed: 12/19/2022] Open
Abstract
Skeletal muscle fibers are multinucleated cells that contain mostly myofibrils suspended in an aqueous media termed the sarcoplasm. Select evidence suggests sarcoplasmic hypertrophy, or a disproportionate expansion of the sarcoplasm relative to myofibril protein accretion, coincides with muscle fiber or tissue growth during resistance training. There is also evidence to support other modes of hypertrophy occur during periods of resistance training including a proportional accretion of myofibril protein with fiber or tissue growth (i.e., conventional hypertrophy), or myofibril protein accretion preceding fiber or tissue growth (i.e., myofibril packing). In this review, we discuss methods that have been used to investigate these modes of hypertrophy. Particular attention is given to sarcoplasmic hypertrophy throughout. Thus, descriptions depicting this process as well as the broader implications of this phenomenon will be posited. Finally, we propose future human and rodent research that can further our understanding in this area of muscle physiology.
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Affiliation(s)
- Michael D Roberts
- School of Kinesiology, Auburn, AL, United States.,Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine - Auburn Campus, Auburn, AL, United States
| | - Cody T Haun
- Fitomics, LLC, Birmingham, AL, United States
| | | | | | - Kaelin C Young
- School of Kinesiology, Auburn, AL, United States.,Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine - Auburn Campus, Auburn, AL, United States
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29
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Jorgenson KW, Phillips SM, Hornberger TA. Identifying the Structural Adaptations that Drive the Mechanical Load-Induced Growth of Skeletal Muscle: A Scoping Review. Cells 2020; 9:cells9071658. [PMID: 32660165 PMCID: PMC7408414 DOI: 10.3390/cells9071658] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 07/06/2020] [Accepted: 07/07/2020] [Indexed: 12/21/2022] Open
Abstract
The maintenance of skeletal muscle mass plays a critical role in health and quality of life. One of the most potent regulators of skeletal muscle mass is mechanical loading, and numerous studies have led to a reasonably clear understanding of the macroscopic and microscopic changes that occur when the mechanical environment is altered. For instance, an increase in mechanical loading induces a growth response that is mediated, at least in part, by an increase in the cross-sectional area of the myofibers (i.e., myofiber hypertrophy). However, very little is known about the ultrastructural adaptations that drive this response. Even the most basic questions, such as whether mechanical load-induced myofiber hypertrophy is mediated by an increase in the size of the pre-existing myofibrils and/or an increase in the number myofibrils, have not been resolved. In this review, we thoroughly summarize what is currently known about the macroscopic, microscopic and ultrastructural changes that drive mechanical load-induced growth and highlight the critical gaps in knowledge that need to be filled.
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Affiliation(s)
- Kent W. Jorgenson
- School of Veterinary Medicine and the Department of Comparative Biosciences, University of Wisconsin, Madison, WI 53706, USA;
| | - Stuart M. Phillips
- Department of Kinesiology, McMaster University, Hamilton, ON L8S 4K1, Canada;
| | - Troy A. Hornberger
- School of Veterinary Medicine and the Department of Comparative Biosciences, University of Wisconsin, Madison, WI 53706, USA;
- Correspondence:
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30
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Rice PE, Nimphius S. When Task Constraints Delimit Movement Strategy: Implications for Isolated Joint Training in Dancers. Front Sports Act Living 2020; 2:49. [PMID: 33345041 PMCID: PMC7739566 DOI: 10.3389/fspor.2020.00049] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 04/07/2020] [Indexed: 12/18/2022] Open
Abstract
Athletic performance is determined by numerous variables that cannot always be controlled or modified. Due to aesthetic requirements during sports such as dance, body alignment constrains possible movement solutions. Increased power transference around the ankle-joint, coupled with lower hip-joint power, has become a preferential strategy in dancers during leaps and may be considered a dance-specific stretch-shortening cycle (SSC) demand. Newell's theoretical model of interacting constraints includes organismic (or individual), environmental, and task constraints describing the different endogenous and exogenous constraints individuals must overcome for movement and athletic performance. The unique task constraints imposed during dance will be used as a model to justify an isolated joint, single-targeted block progression training to improve physical capacity within the context of motor behavior to enhance dance-specific SSC performance. The suggested ankle-specific block progression consists of isometrics, dynamic constant external resistance, accentuated eccentrics, and plyometrics. Such programming tactics intend to collectively induce tendon remodeling, muscle hypertrophy, greater maximal strength, improved rate of force development, increased motor unit firing rates, and enhanced dynamic movement performance. The current perspective provides a dualistic approach and justification (physiological and motor behavioral) for specific strength and conditioning programming strategies. We propose implementation of a single-targeted block progression program, inspired by Newell's theoretical model of interacting constraints, may elicit positive training adaptations in a directed manner in this population. The application of Newell's theoretical model in the context of a strength and conditioning supports development of musculoskeletal properties and control and is conceptually applicable to a range of athletes.
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Affiliation(s)
- Paige E Rice
- Centre for Exercise and Sports Science Research, School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia.,Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, United States
| | - Sophia Nimphius
- Centre for Exercise and Sports Science Research, School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia.,Sports Performance Research Institute New Zealand, Auckland University of Technology, Auckland, New Zealand
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31
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Exercise-Induced Myofibrillar Hypertrophy is a Contributory Cause of Gains in Muscle Strength. Sports Med 2020; 49:993-997. [PMID: 31016546 DOI: 10.1007/s40279-019-01107-8] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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32
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Cui D, Drake JC, Wilson RJ, Shute RJ, Lewellen B, Zhang M, Zhao H, Sabik OL, Onengut S, Berr SS, Rich SS, Farber CR, Yan Z. A novel voluntary weightlifting model in mice promotes muscle adaptation and insulin sensitivity with simultaneous enhancement of autophagy and mTOR pathway. FASEB J 2020; 34:7330-7344. [PMID: 32304342 DOI: 10.1096/fj.201903055r] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 02/17/2020] [Accepted: 03/04/2020] [Indexed: 12/23/2022]
Abstract
Our understanding of the molecular mechanisms underlying adaptations to resistance exercise remains elusive despite the significant biological and clinical relevance. We developed a novel voluntary mouse weightlifting model, which elicits squat-like activities against adjustable load during feeding, to investigate the resistance exercise-induced contractile and metabolic adaptations. RNAseq analysis revealed that a single bout of weightlifting induced significant transcriptome responses of genes that function in posttranslational modification, metabolism, and muscle differentiation in recruited skeletal muscles, which were confirmed by increased expression of fibroblast growth factor-inducible 14 (Fn14), Down syndrome critical region 1 (Dscr1) and Nuclear receptor subfamily 4, group A, member 3 (Nr4a3) genes. Long-term (8 weeks) voluntary weightlifting training resulted in significantly increases of muscle mass, protein synthesis (puromycin incorporation in SUnSET assay) and mTOR pathway protein expression (raptor, 4e-bp-1, and p70S6K proteins) along with enhanced muscle power (specific torque and contraction speed), but not endurance capacity, mitochondrial biogenesis, and fiber type transformation. Importantly, weightlifting training profound improved whole-body glucose clearance and skeletal muscle insulin sensitivity along with enhanced autophagy (increased LC3 and LC3-II/I ratio, and decreased p62/Sqstm1). These data suggest that resistance training in mice promotes muscle adaptation and insulin sensitivity with simultaneous enhancement of autophagy and mTOR pathway.
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Affiliation(s)
- Di Cui
- Center for Skeletal Muscle Research at Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA.,Key Laboratory of Adolescent and Exercise Intervention, Ministry of Education, East China Normal University, Shanghai, China
| | - Joshua C Drake
- Center for Skeletal Muscle Research at Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Rebecca J Wilson
- Center for Skeletal Muscle Research at Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA.,Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Robert J Shute
- Center for Skeletal Muscle Research at Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Bevan Lewellen
- Center for Skeletal Muscle Research at Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Mei Zhang
- Center for Skeletal Muscle Research at Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA.,Departments of Medicine, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Henan Zhao
- Center for Skeletal Muscle Research at Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Olivia L Sabik
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA, USA.,Center for Public Health Genomics, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Suna Onengut
- Center for Public Health Genomics, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Stuart S Berr
- Department of Radiology and Medical Imaging, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Stephen S Rich
- Center for Public Health Genomics, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Charles R Farber
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA, USA.,Center for Public Health Genomics, University of Virginia School of Medicine, Charlottesville, VA, USA.,Department of Public Health Sciences, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Zhen Yan
- Center for Skeletal Muscle Research at Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA, USA.,Departments of Medicine, University of Virginia School of Medicine, Charlottesville, VA, USA.,Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA, USA.,Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA, USA
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Methenitis S, Mpampoulis T, Spiliopoulou P, Papadimas G, Papadopoulos C, Chalari E, Evangelidou E, Stasinaki AN, Nomikos T, Terzis G. Muscle fiber composition, jumping performance, and rate of force development adaptations induced by different power training volumes in females. Appl Physiol Nutr Metab 2020; 45:996-1006. [PMID: 32203677 DOI: 10.1139/apnm-2019-0786] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study aimed to investigate the effect of 3 different eccentric-only power training volumes on muscle fiber type composition and power performance. Twenty-nine females were assigned into 3 groups and performed 10 weeks of either 3 (low volume), 6 (moderate volume), or 9 (high volume) sets/session of 4 fast-velocity eccentric-only half-squats against 70% of concentric 1-repetition maximum (1RM), followed by 3 maximum countermovement jumps (CMJs) after each set. Half-squat 1RM, CMJ height/power, maximum isometric force, rate of force development (RFD) and muscle fiber cross-sectional area (CSA) were increased in all groups (p = 0.001). Low-volume training induced higher increases in CMJ height/power and early RFD, compared with the moderate- and high-volume training programs (p < 0.001). Significant reductions in type IIx muscle fiber percentages and %CSAs were found after moderate- and high-volume training, with concomitant increases in type IIa fibers (p = 0.001). Significant correlations were found between the changes in type IIa and type IIx percentages, fiber CSA, %CSA, and the changes in performance (r: -0.787 to 0.792; p < 0.05). These results suggest that relatively large eccentric power training volumes may result in detrimental neuromuscular adaptations, minimal changes in early RFD, and a reduction of type IIx muscle fiber percentage. Novelty Low but not high volume of power training maintains type IIx muscle fibers. Early rate of force development increases after a low- or moderate-power training volume, but not after a high-power training volume. Training-induced changes in type IIx muscle fiber percentage is related with changes in early rate of force development.
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Affiliation(s)
- Spyridon Methenitis
- Sports Performance Laboratory, School of Physical Education & Sports Science, National and Kapodistrian University of Athens, 172 37, Daphne, Athens, Greece
| | - Thomas Mpampoulis
- Sports Performance Laboratory, School of Physical Education & Sports Science, National and Kapodistrian University of Athens, 172 37, Daphne, Athens, Greece
| | - Polyxeni Spiliopoulou
- Sports Performance Laboratory, School of Physical Education & Sports Science, National and Kapodistrian University of Athens, 172 37, Daphne, Athens, Greece
| | - George Papadimas
- A'Neurology Clinic, Aiginition Hospital, Medical School, National and Kapodistrian University of Athens, Leof. Vasilissis Sofias 72, Athina 115 28, Greece
| | - Constantinos Papadopoulos
- A'Neurology Clinic, Aiginition Hospital, Medical School, National and Kapodistrian University of Athens, Leof. Vasilissis Sofias 72, Athina 115 28, Greece
| | - Eleanna Chalari
- Department of Nutrition and Dietetics, School of Health Science & Education, Harokopio University of Athens, 70 El. Venizelou, 17671 Athens, Greece
| | - Eftychia Evangelidou
- Department of Infection Control, G.N.N. Ionias "Konstantopouleio-Patision" Hospital, Agias Olgas 3-5, 14233, Nea Ionia, Greece
| | - Angeliki-Nikoletta Stasinaki
- Sports Performance Laboratory, School of Physical Education & Sports Science, National and Kapodistrian University of Athens, 172 37, Daphne, Athens, Greece
| | - Tzortzis Nomikos
- Department of Nutrition and Dietetics, School of Health Science & Education, Harokopio University of Athens, 70 El. Venizelou, 17671 Athens, Greece
| | - Gerasimos Terzis
- Sports Performance Laboratory, School of Physical Education & Sports Science, National and Kapodistrian University of Athens, 172 37, Daphne, Athens, Greece
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Pallone G, Palmieri M, Cariati I, Bei R, Masuelli L, D'Arcangelo G, Tancredi V. Different continuous training modalities result in distinctive effects on muscle structure, plasticity and function. Biomed Rep 2020; 12:267-275. [PMID: 32257190 DOI: 10.3892/br.2020.1283] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 12/13/2019] [Indexed: 12/18/2022] Open
Abstract
The effects of training on muscle structure are dependent on adaptive changes induced by different intensities of physical exercise. Evidence has shown that aerobic training is able to induce adaptive changes to muscle structure based on intensity. The aim of the present study was to investigate the effects of different methods of continuous aerobic training in mice using functional, morphological and biomolecular approaches. The continuous aerobic training methods used in the present study were uniform continuous training (UC), varying continuous training (VC) and progressive continuous training (PC). Mice were made to run 3 times a week for 12 weeks on a motorized RotaRod, following one of the three different training methods at different speeds. The results of the present study demonstrated that the various training methods had different effects on sarcomere length. Ultrastructural analysis demonstrated that UC training resulted in a shortening of sarcomere length, PC training resulted in an elongation of sarcomere length and VC training showed similar sarcomere length when compared with the control sedentary group. Additionally, succinate dehydrogenase complex flavoprotein subunit A levels in muscle tissue following VC training were higher compared with UC and PC training. Overall, the present study showed that varying exercise methods resulted in different types of muscle plasticity, and that the VC protocol resulted in increased coordination and strength endurance in the functional tests, in agreement with the ultrastructural and biochemical profile. These observations support the view that VC training may be more efficient in increasing performance and may thus form the basis of training regimens when an improvement of motor efficiency is required.
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Affiliation(s)
- Gabriele Pallone
- Department of Systems Medicine, University of Rome Tor Vergata, I-00133 Rome, Italy
| | - Mattia Palmieri
- Department of Systems Medicine, University of Rome Tor Vergata, I-00133 Rome, Italy
| | - Ida Cariati
- Department of Systems Medicine, University of Rome Tor Vergata, I-00133 Rome, Italy
| | - Roberto Bei
- Department of Clinical Sciences and Translational Medicine, University of Rome Tor Vergata, I-00133 Rome, Italy
| | - Laura Masuelli
- Department of Experimental Medicine, Sapienza University of Rome, I-00161 Rome, Italy
| | - Giovanna D'Arcangelo
- Department of Systems Medicine, University of Rome Tor Vergata, I-00133 Rome, Italy.,Centre of Space Bio-medicine, University of Rome Tor Vergata, I-00133 Rome, Italy
| | - Virginia Tancredi
- Department of Systems Medicine, University of Rome Tor Vergata, I-00133 Rome, Italy.,Centre of Space Bio-medicine, University of Rome Tor Vergata, I-00133 Rome, Italy
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35
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Hammarström D, Øfsteng S, Koll L, Hanestadhaugen M, Hollan I, Apró W, Whist JE, Blomstrand E, Rønnestad BR, Ellefsen S. Benefits of higher resistance-training volume are related to ribosome biogenesis. J Physiol 2020; 598:543-565. [PMID: 31813190 DOI: 10.1113/jp278455] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 12/03/2019] [Indexed: 12/25/2022] Open
Abstract
KEY POINTS For individuals showing suboptimal adaptations to resistance training, manipulation of training volume is a potential measure to facilitate responses. This remains unexplored. Here, 34 untrained individuals performed contralateral resistance training with moderate and low volume for 12 weeks. Moderate volume led to larger increases in muscle cross-sectional area, strength and type II fibre-type transitions. These changes coincided with greater activation of signalling pathways controlling muscle growth and greater induction of ribosome synthesis. Out of 34 participants, thirteen displayed clear benefit of MOD on muscle hypertrophy and sixteen showed clear benefit of MOD on muscle strength gains. This coincided with greater total RNA accumulation in the early phase of the training period, suggesting that ribosomal biogenesis regulates the dose-response relationship between training volume and muscle hypertrophy. These results demonstrate that there is a dose-dependent relationship between training volume and outcomes. On the individual level, benefits of higher training volume were associated with increased ribosomal biogenesis. ABSTRACT Resistance-exercise volume is a determinant of training outcomes. However not all individuals respond in a dose-dependent fashion. In this study, 34 healthy individuals (males n = 16, 23.6 (4.1) years; females n = 18, 22.0 (1.3) years) performed moderate- (3 sets per exercise, MOD) and low-volume (1 set, LOW) resistance training in a contralateral fashion for 12 weeks (2-3 sessions per week). Muscle cross-sectional area (CSA) and strength were assessed at Weeks 0 and 12, along with biopsy sampling (m. vastus lateralis). Muscle biopsies were also sampled before and 1 h after the fifth session (Week 2). MOD resulted in larger increases in muscle CSA (5.2 (3.8)% versus 3.7 (3.7)%, P < 0.001) and strength (3.4-7.7% difference, all P < 0.05. This coincided with greater reductions in type IIX fibres from Week 0 to Week 12 (MOD, -4.6 percentage points; LOW -3.2 percentage points), greater phosphorylation of S6-kinase 1 (p85 S6K1Thr412 , 19%; p70 S6K1Thr389 , 58%) and ribosomal protein S6Ser235/236 (37%), greater rested-state total RNA (8.8%) and greater exercise-induced c-Myc mRNA expression (25%; Week 2, all P < 0.05). Thirteen and sixteen participants, respectively, displayed clear benefits in response to MOD on muscle hypertrophy and strength. Benefits were associated with greater accumulation of total RNA at Week 2 in the MOD leg, with every 1% difference increasing the odds of MOD benefit by 7.0% (P = 0.005) and 9.8% (P = 0.002). In conclusion, MOD led to greater functional and biological adaptations than LOW. Associations between dose-dependent total RNA accumulation and increases in muscle mass and strength point to ribosome biogenesis as a determinant of dose-dependent training responses.
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Affiliation(s)
- Daniel Hammarström
- Section for Health and Exercise Physiology, Department of Public Health and Sport Sciences, Inland Norway University of Applied Sciences, Elverum, Norway.,Swedish School of Sport and Health Sciences, Box 5626, SE-114 86, Stockholm, Sweden
| | - Sjur Øfsteng
- Section for Health and Exercise Physiology, Department of Public Health and Sport Sciences, Inland Norway University of Applied Sciences, Elverum, Norway
| | - Lise Koll
- Innlandet Hospital Trust, Postboks 990, 2629, Lillehammer, Norway
| | | | - Ivana Hollan
- Hospital for Rheumatic Diseases, Magrethe Grundtvigsvei 6, 2609, Lillehammer, Norway.,Brigham and Women's Hospital, 75 Francis Street, Boston, MA, 02115, USA
| | - William Apró
- Swedish School of Sport and Health Sciences, Box 5626, SE-114 86, Stockholm, Sweden
| | - Jon Elling Whist
- Innlandet Hospital Trust, Postboks 990, 2629, Lillehammer, Norway
| | - Eva Blomstrand
- Swedish School of Sport and Health Sciences, Box 5626, SE-114 86, Stockholm, Sweden
| | - Bent R Rønnestad
- Section for Health and Exercise Physiology, Department of Public Health and Sport Sciences, Inland Norway University of Applied Sciences, Elverum, Norway
| | - Stian Ellefsen
- Section for Health and Exercise Physiology, Department of Public Health and Sport Sciences, Inland Norway University of Applied Sciences, Elverum, Norway.,Innlandet Hospital Trust, Postboks 990, 2629, Lillehammer, Norway
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Gries KJ, Minchev K, Raue U, Grosicki GJ, Begue G, Finch WH, Graham B, Trappe TA, Trappe S. Single-muscle fiber contractile properties in lifelong aerobic exercising women. J Appl Physiol (1985) 2019; 127:1710-1719. [PMID: 31670601 PMCID: PMC6962607 DOI: 10.1152/japplphysiol.00459.2019] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 10/22/2019] [Accepted: 10/25/2019] [Indexed: 01/05/2023] Open
Abstract
The purpose of this study was to examine the effects of lifelong aerobic exercise on single-muscle fiber performance in trained women (LLE; n = 7, 72 ± 2 yr) by comparing them to old healthy nonexercisers (OH; n = 10, 75 ± 1 yr) and young exercisers (YE; n = 10, 25 ± 1 yr). On average, LLE had exercised ~5 days/wk for ~7 h/wk over the past 48 ± 2 yr. Each subject had a vastus lateralis muscle biopsy to examine myosin heavy chain (MHC) I and IIa single-muscle fiber size and function (strength, speed, power). MHC I fiber size was similar across all three cohorts (YE = 5,178 ± 157, LLE = 4,983 ± 184, OH = 4,902 ± 159 µm2). MHC IIa fiber size decreased (P < 0.05) 36% with aging (YE = 4,719 ± 164 vs. OH = 3,031 ± 153 µm2), with LLE showing a similar 31% reduction (3,253 ± 189 µm2). LLE had 17% more powerful (P < 0.05) MHC I fibers and offset the 18% decline in MHC IIa fiber power observed with aging (P < 0.05). The LLE contractile power was driven by greater strength (+11%, P = 0.056) in MHC I fibers and elevated contractile speed (+12%, P < 0.05) in MHC IIa fibers. These data indicate that lifelong exercise did not benefit MHC I or IIa muscle fiber size. However, LLE had contractile function adaptations that enhanced MHC I fiber power and preserved MHC IIa fiber power through different contractile mechanisms (strength vs. speed). The single-muscle fiber contractile properties observed with lifelong aerobic exercise are unique and provide new insights into aging skeletal muscle plasticity in women at the myocellular level.NEW & NOTEWORTHY This is the first investigation to examine the effects of lifelong exercise on single-muscle fiber physiology in women. Nearly 50 yr of moderate to vigorous aerobic exercise training resulted in enhanced slow-twitch fiber power primarily by increasing force production, whereas fast-twitch fiber power was preserved primarily by increasing contractile speed. These unique muscle fiber power profiles helped offset the effects of fast-twitch fiber atrophy and highlight the benefits of lifelong aerobic exercise for myocellular health.
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Affiliation(s)
- Kevin J Gries
- Human Performance Laboratory, Ball State University, Muncie, Indiana
| | - Kiril Minchev
- Human Performance Laboratory, Ball State University, Muncie, Indiana
| | - Ulrika Raue
- Human Performance Laboratory, Ball State University, Muncie, Indiana
| | | | - Gwénaëlle Begue
- Human Performance Laboratory, Ball State University, Muncie, Indiana
| | - W Holmes Finch
- Human Performance Laboratory, Ball State University, Muncie, Indiana
| | - Bruce Graham
- Human Performance Laboratory, Ball State University, Muncie, Indiana
| | - Todd A Trappe
- Human Performance Laboratory, Ball State University, Muncie, Indiana
| | - Scott Trappe
- Human Performance Laboratory, Ball State University, Muncie, Indiana
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Jeon Y, Choi J, Kim HJ, Lee H, Lim JY, Choi SJ. Sex- and fiber-type-related contractile properties in human single muscle fiber. J Exerc Rehabil 2019; 15:537-545. [PMID: 31523674 PMCID: PMC6732543 DOI: 10.12965/jer.1938336.168] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Accepted: 07/09/2019] [Indexed: 11/22/2022] Open
Abstract
This study aimed to examine the distribution and contractile properties of single muscle fiber sex/myosin heavy chain (MHC) type-related differences and to evaluate the correlation of cross-sectional area (CSA) and specific force (SF) in a single muscle fiber. Six young men and six young women were participated in this study. Muscle sample was obtained from vastus lateralis muscle. To examine potential gender differences within each fiber contractile properties (CSA, maximal isometric force, SF, maximal shortening velocity) and relationship between CSA and SF of single fiber using Pearson correlation. After mechanical measurements, single muscle fiber determined MHC isoforms using silver stain. MHC isoform composition did not differ by sex (chi-square=6.978, P=0.073). There were sex-related differences in CSA and maximal isometric force (P<0.05), but no fiber type-related differences (P>0.05). Related to SF and maximal shortening velocity, there were no sex-related differences only fiber type-related differences (P<0.05). However, there were differences in SF between single fiber types in men but not in women. A negative correlation was found between CSA and SF in both men and women (P<0.05). It is suggested that there might be different mechanical properties of cross-bridges according to sex.
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Affiliation(s)
- Yunah Jeon
- Division of Sports and Health Science, Kyungsung University, Busan, Korea.,Mechanical & Molecular Myology Lab, Department of Rehabilitation Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea
| | - Junghwa Choi
- Division of Sports and Health Science, Kyungsung University, Busan, Korea
| | - Hee Jaeng Kim
- Division of Sports and Health Science, Kyungsung University, Busan, Korea
| | - Hojun Lee
- Division of Sports and Health Science, Kyungsung University, Busan, Korea.,Mechanical & Molecular Myology Lab, Department of Rehabilitation Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea
| | - Jae-Young Lim
- Mechanical & Molecular Myology Lab, Department of Rehabilitation Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam, Korea
| | - Seung-Jun Choi
- Division of Sports and Health Science, Kyungsung University, Busan, Korea
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38
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Muddle TW, Magrini MA, Colquhoun RJ, Luera MJ, Tomko PM, Jenkins ND. Impact of Fatiguing, Submaximal High- vs. Low-Torque Isometric Exercise on Acute Muscle Swelling, and Echo Intensity in Resistance-Trained Men. J Strength Cond Res 2019; 33:1007-1019. [DOI: 10.1519/jsc.0000000000003033] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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39
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Resistance training induced changes in strength and specific force at the fiber and whole muscle level: a meta-analysis. Eur J Appl Physiol 2018; 119:265-278. [DOI: 10.1007/s00421-018-4022-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 10/18/2018] [Indexed: 01/08/2023]
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40
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Bourdeau Julien I, Sephton CF, Dutchak PA. Metabolic Networks Influencing Skeletal Muscle Fiber Composition. Front Cell Dev Biol 2018; 6:125. [PMID: 30324104 PMCID: PMC6172607 DOI: 10.3389/fcell.2018.00125] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 09/10/2018] [Indexed: 12/19/2022] Open
Abstract
Advancements in metabolomic and genomic research tools are revealing new insights into how metabolic networks can influence skeletal muscle fiber composition. In this mini-review, we summarize the recent progress of metabolite-dependent signaling pathways and transcriptional regulators that control glycolytic and oxidative metabolism and ultimately influence the type of fibers in muscle depots. These mechanisms expand the role of metabolites beyond that of basic building blocks of cellular components, and illustrate how particular metabolites can take an active role in regulating metabolic homeostasis and fiber adaptation. As new metabolite-dependent mechanisms emerge, ongoing metabolomic studies have begun to help explain why distinct metabolic pathways are used in different biological contexts and widen the view of seminal observations like the Warburg effect.
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Affiliation(s)
- Isabelle Bourdeau Julien
- Department of Psychiatry and Neuroscience, Université Laval, Quebec, QC, Canada.,CERVO Brain Research Centre, Quebec, QC, Canada
| | - Chantelle F Sephton
- Department of Psychiatry and Neuroscience, Université Laval, Quebec, QC, Canada.,CERVO Brain Research Centre, Quebec, QC, Canada
| | - Paul A Dutchak
- Department of Psychiatry and Neuroscience, Université Laval, Quebec, QC, Canada.,CERVO Brain Research Centre, Quebec, QC, Canada
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41
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Taverne M, Fabre AC, Herbin M, Herrel A, Peigné S, Lacroux C, Lowie A, Pagès F, Theil JC, Böhmer C. Convergence in the functional properties of forelimb muscles in carnivorans: adaptations to an arboreal lifestyle? Biol J Linn Soc Lond 2018. [DOI: 10.1093/biolinnean/bly123] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Maxime Taverne
- UMR 7179, Muséum National d’Histoire Naturelle, Centre National de la Recherche Scientifique, Département Adaptations du Vivant, rue Buffon, Paris, France
| | - Anne-Claire Fabre
- UMR 7179, Muséum National d’Histoire Naturelle, Centre National de la Recherche Scientifique, Département Adaptations du Vivant, rue Buffon, Paris, France
| | - Marc Herbin
- UMR 7179, Muséum National d’Histoire Naturelle, Centre National de la Recherche Scientifique, Département Adaptations du Vivant, rue Buffon, Paris, France
| | - Anthony Herrel
- UMR 7179, Muséum National d’Histoire Naturelle, Centre National de la Recherche Scientifique, Département Adaptations du Vivant, rue Buffon, Paris, France
| | - Stéphane Peigné
- UMR 7207 – CR2P, CNRS/MNHN, Département Origines et Evolution, rue Buffon, Paris, France
| | - Camille Lacroux
- UMR 7179, Muséum National d’Histoire Naturelle, Centre National de la Recherche Scientifique, Département Adaptations du Vivant, rue Buffon, Paris, France
| | - Aurélien Lowie
- UMR 7179, Muséum National d’Histoire Naturelle, Centre National de la Recherche Scientifique, Département Adaptations du Vivant, rue Buffon, Paris, France
| | - Fanny Pagès
- UMR 7179, Muséum National d’Histoire Naturelle, Centre National de la Recherche Scientifique, Département Adaptations du Vivant, rue Buffon, Paris, France
| | - Jean-Christophe Theil
- UMR 7179, Muséum National d’Histoire Naturelle, Centre National de la Recherche Scientifique, Département Adaptations du Vivant, rue Buffon, Paris, France
| | - Christine Böhmer
- UMR 7179, Muséum National d’Histoire Naturelle, Centre National de la Recherche Scientifique, Département Adaptations du Vivant, rue Buffon, Paris, France
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42
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Effects of aerobic training, resistance training, or both on circulating irisin and myostatin in untrained women. ACTA GYMNICA 2018. [DOI: 10.5507/ag.2018.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
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43
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Alavizadeh NS, Rashidlamir A, Hejazi SM. Effect of Eight Weeks Aerobic and Combined Training on Serum Levels of Sirtuin 1 and PGC-1α in Coronary Artery Bypass Graft Patients. MEDICAL LABORATORY JOURNAL 2018. [DOI: 10.29252/mlj.12.5.50] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
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44
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Abstract
Greater levels of bone ultimate fracture load, bone stress–strain index, muscle cross-sectional area, and maximal voluntary isometric plantarflexion (MVIP) strength of the lower leg may be adaptations from chronic exposure to stretch-shortening cycle (SSC) actions. Dancers, a population that habitually performs SSC movements primarily about the ankle joint, may serve as a novel population to gain broader understanding of SSC function. A total of 10 female collegiate dancers and 10 untrained controls underwent peripheral quantitative computed tomography scans of both lower legs and performed MVIPs, countermovement hops, and drop hops at 20, 30, and 40 cm on a custom-made inclined sled. Dancers had greater right and left ultimate fracture load values and significantly (P ≤ .05) greater left leg stress–strain index than controls. Dancers had significantly larger right and left muscle cross-sectional area and MVIP values and hopped significantly higher during all hopping conditions in comparison with controls. Average force–time and power–time curves revealed significantly greater relative force and power measurements during the concentric phase for all hopping conditions in dancers when compared with controls. This investigation provides evidence that dance may be a stimulus for positive muscle and bone adaptations, strength levels, and enhanced SSC capabilities.
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45
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D'Souza RF, Zeng N, Markworth JF, Figueiredo VC, Roberts LA, Raastad T, Coombes JS, Peake JM, Cameron-Smith D, Mitchell CJ. Divergent effects of cold water immersion versus active recovery on skeletal muscle fiber type and angiogenesis in young men. Am J Physiol Regul Integr Comp Physiol 2018; 314:R824-R833. [PMID: 29466686 DOI: 10.1152/ajpregu.00421.2017] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Resistance training (RT) increases muscle fiber size and induces angiogenesis to maintain capillary density. Cold water immersion (CWI), a common postexercise recovery modality, may improve acute recovery, but it attenuates muscle hypertrophy compared with active recovery (ACT). It is unknown if CWI following RT alters muscle fiber type expression or angiogenesis. Twenty-one men strength trained for 12 wk, with either 10 min of CWI ( n = 11) or ACT ( n = 10) performed following each session. Vastus lateralis biopsies were collected at rest before and after training. Type IIx myofiber percent decreased ( P = 0.013) and type IIa myofiber percent increased with training ( P = 0.012), with no difference between groups. The number of capillaries per fiber increased from pretraining in the CWI group ( P = 0.004) but not the ACT group ( P = 0.955). Expression of myosin heavy chain genes ( MYH1 and MYH2), encoding type IIx and IIa fibers, respectively, decreased in the ACT group, whereas MYH7 (encoding type I fibers) increased in the ACT group versus CWI ( P = 0.004). Myosin heavy chain IIa protein increased with training ( P = 0.012) with no difference between groups. The proangiogenic vascular endothelial growth factor protein decreased posttraining in the ACT group versus CWI ( P < 0.001), whereas antiangiogenic Sprouty-related, EVH1 domain-containing protein 1 protein increased with training in both groups ( P = 0.015). Expression of microRNAs that regulate muscle fiber type (miR-208b and -499a) and angiogenesis (miR-15a, -16, and -126) increased only in the ACT group ( P < 0.05). CWI recovery after each training session altered the angiogenic and fiber type-specific response to RT through regulation at the levels of microRNA, gene, and protein expression.
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Affiliation(s)
- Randall F D'Souza
- Liggins Institute, The University of Auckland , Auckland , New Zealand
| | - Nina Zeng
- Liggins Institute, The University of Auckland , Auckland , New Zealand
| | - James F Markworth
- Liggins Institute, The University of Auckland , Auckland , New Zealand
| | - Vandre C Figueiredo
- Liggins Institute, The University of Auckland , Auckland , New Zealand.,Center for Muscle Biology, University of Kentucky , Lexington, Kentucky
| | - Llion A Roberts
- School of Human Movement and Nutrition Sciences, University of Queensland , Brisbane , Australia.,Sports Performance Innovation and Knowledge Excellence, Queensland Academy of Sport , Brisbane , Australia.,School of Allied Health Sciences & Menzies Health Institute Queensland, Griffith University , Gold Coast, Queensland , Australia
| | - Truls Raastad
- Department of Physical Performance, Norwegian School of Sport Sciences , Oslo , Norway
| | - Jeff S Coombes
- School of Human Movement and Nutrition Sciences, University of Queensland , Brisbane , Australia
| | - Jonathan M Peake
- Sports Performance Innovation and Knowledge Excellence, Queensland Academy of Sport , Brisbane , Australia.,School of Biomedical Sciences and Institute of Health and Biomedical Innovation, Queensland University of Technology , Brisbane Australia
| | - David Cameron-Smith
- Liggins Institute, The University of Auckland , Auckland , New Zealand.,Food & Bio-Based Products Group, AgResearch, Palmerston North , New Zealand.,Riddet Institute , Palmerston North , New Zealand
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46
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Tucci S, Mingirulli N, Wehbe Z, Dumit VI, Kirschner J, Spiekerkoetter U. Mitochondrial fatty acid biosynthesis and muscle fiber plasticity in very long-chain acyl-CoA dehydrogenase-deficient mice. FEBS Lett 2018; 592:219-232. [PMID: 29237229 DOI: 10.1002/1873-3468.12940] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 11/27/2017] [Accepted: 12/04/2017] [Indexed: 12/31/2022]
Abstract
The white skeletal muscle of very long-chain acyl-CoA-dehydrogenase-deficient (VLCAD-/- ) mice undergoes metabolic modification to compensate for defective β-oxidation in a progressive and time-dependent manner by upregulating glucose oxidation. This metabolic regulation seems to be accompanied by morphologic adaptation of muscle fibers toward the glycolytic fiber type II with the concomitant upregulation of mitochondrial fatty acid biosynthesis (mFASII) and lipoic acid biosynthesis. Dietary supplementation of VLCAD-/- mice with different medium-chain triglycerides over 1 year revealed that odd-chain species has no effect on muscle fiber switch, whereas even-chain species inhibit progressive metabolic adaptation. Our study shows that muscle may undergo adaptive mechanisms that are modulated by dietary supplementation. We describe for the first time a concomitant change of mFASII in this muscular adaptation process.
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Affiliation(s)
- Sara Tucci
- Department of General Pediatrics, Center for Paediatrics and Adolescent Medicine, Faculty of Medicine and Medical Centre, University of Freiburg, Germany
| | - Nadja Mingirulli
- Department of General Pediatrics, Center for Paediatrics and Adolescent Medicine, Faculty of Medicine and Medical Centre, University of Freiburg, Germany
| | - Zeinab Wehbe
- Department of General Pediatrics, Center for Paediatrics and Adolescent Medicine, Faculty of Medicine and Medical Centre, University of Freiburg, Germany
| | - Verónica I Dumit
- Core Facility Proteomics, Center for Biological Systems Analysis (ZBSA), University of Freiburg, Germany
| | - Janbernd Kirschner
- Department of Neuropaediatrics, Center for Paediatrics and Adolescent Medicine, Faculty of Medicine and Medical Centre, University of Freiburg, Germany
| | - Ute Spiekerkoetter
- Department of General Pediatrics, Center for Paediatrics and Adolescent Medicine, Faculty of Medicine and Medical Centre, University of Freiburg, Germany
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Mersmann F, Bohm S, Arampatzis A. Imbalances in the Development of Muscle and Tendon as Risk Factor for Tendinopathies in Youth Athletes: A Review of Current Evidence and Concepts of Prevention. Front Physiol 2017; 8:987. [PMID: 29249987 PMCID: PMC5717808 DOI: 10.3389/fphys.2017.00987] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 11/17/2017] [Indexed: 01/09/2023] Open
Abstract
Tendons feature the crucial role to transmit the forces exerted by the muscles to the skeleton. Thus, an increase of the force generating capacity of a muscle needs to go in line with a corresponding modulation of the mechanical properties of the associated tendon to avoid potential harm to the integrity of the tendinous tissue. However, as summarized in the present narrative review, muscle and tendon differ with regard to both the time course of adaptation to mechanical loading as well as the responsiveness to certain types of mechanical stimulation. Plyometric loading, for example, seems to be a more potent stimulus for muscle compared to tendon adaptation. In growing athletes, the increased levels of circulating sex hormones might additionally augment an imbalanced development of muscle strength and tendon mechanical properties, which could potentially relate to the increasing incidence of tendon overload injuries that has been indicated for adolescence. In fact, increased tendon stress and strain due to a non-uniform musculotendinous development has been observed recently in adolescent volleyball athletes, a high-risk group for tendinopathy. These findings highlight the importance to deepen the current understanding of the interaction of loading and maturation and demonstrate the need for the development of preventive strategies. Therefore, this review concludes with an evidence-based concept for a specific loading program for increasing tendon stiffness, which could be implemented in the training regimen of young athletes at risk for tendinopathy. This program incorporates five sets of four contractions with an intensity of 85–90% of the isometric voluntary maximum and a movement/contraction duration that provides 3 s of high magnitude tendon strain.
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Affiliation(s)
- Falk Mersmann
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany.,Berlin School of Movement Science, Berlin, Germany
| | - Sebastian Bohm
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany.,Berlin School of Movement Science, Berlin, Germany
| | - Adamantios Arampatzis
- Department of Training and Movement Sciences, Humboldt-Universität zu Berlin, Berlin, Germany.,Berlin School of Movement Science, Berlin, Germany
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48
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Howe LP, Read P, Waldron M. Muscle Hypertrophy: A Narrative Review on Training Principles for Increasing Muscle Mass. Strength Cond J 2017. [DOI: 10.1519/ssc.0000000000000330] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Krutki P, Mrówczyński W, Bączyk M, Łochyński D, Celichowski J. Adaptations of motoneuron properties after weight-lifting training in rats. J Appl Physiol (1985) 2017; 123:664-673. [DOI: 10.1152/japplphysiol.00121.2017] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 06/01/2017] [Accepted: 06/06/2017] [Indexed: 11/22/2022] Open
Abstract
Resistance training, with repeated short-term and high-intensity exercises, is responsible for an increase in muscle mass and force. The aim of this study was to determine whether such training induces adaptations in the electrophysiological properties of motoneurons innervating the trained muscles and to relate these adaptive changes to previous observations made on motor unit contractile properties. The study was performed on adult male Wistar rats. Animals from the training group were subjected to a 5-wk voluntary progressive weight-lifting program, whereas control rats were restricted to standard cage activity. Intracellular recordings from lumbar spinal motoneurons were made under pentobarbital anesthesia. Membrane properties were measured, and rhythmic firing of motoneurons was analyzed. Strength training evoked adaptive changes in both slow- and fast-type motoneurons, indicating their increased excitability. A shorter spike duration, a higher input resistance, a lower rheobase, a decrease in the minimum current required to evoke rhythmic firing, an increase in the maximum frequencies of the early-state firing (ESF) and the steady-state firing (SSF), and an increase in the respective slopes of the frequency-current ( f/ I) relationship were observed in fast motoneurons of the trained group. The increase in the maximum ESF and SSF frequencies and an increase in the SSF f/ I slope were also present in slow motoneurons. Higher maximum firing rates of motoneurons as well as higher discharge frequencies evoked at the same level of intracellular depolarization current imply higher levels of tetanic forces developed by motor units over the operating range of force production after strength training. NEW & NOTEWORTHY Neuronal responses to weight-lifting training can be observed in altered properties of both slow and fast motoneurons. Motoneurons of trained animals are more excitable, require lower intracellular currents to evoke rhythmic firing, and have the ability to evoke higher maximum discharge frequencies during repetitive firing.
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Affiliation(s)
- Piotr Krutki
- Department of Neurobiology, Poznań University of Physical Education, Poznań, Poland; and
| | | | - Marcin Bączyk
- Department of Neurobiology, Poznań University of Physical Education, Poznań, Poland; and
| | - Dawid Łochyński
- Department of Musculoskeletal Rehabilitation, Poznań University of Physical Education, Poznań, Poland
| | - Jan Celichowski
- Department of Neurobiology, Poznań University of Physical Education, Poznań, Poland; and
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Andersen JL, Gruschy-Knudsen T. Rapid switch-off of the human myosin heavy chain IIX gene after heavy load muscle contractions is sustained for at least four days. Scand J Med Sci Sports 2017; 28:371-380. [DOI: 10.1111/sms.12914] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/12/2017] [Indexed: 12/19/2022]
Affiliation(s)
- J. L. Andersen
- Institute of Sports Medicine; Bispebjerg Hospital and Center for Healthy Aging; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen Denmark
| | - T. Gruschy-Knudsen
- Institute of Sports Medicine; Bispebjerg Hospital and Center for Healthy Aging; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen Denmark
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