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Slysz JT, Burr JF. Enhanced Metabolic Stress Augments Ischemic Preconditioning for Exercise Performance. Front Physiol 2018; 9:1621. [PMID: 30498458 PMCID: PMC6249303 DOI: 10.3389/fphys.2018.01621] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 10/26/2018] [Indexed: 02/05/2023] Open
Abstract
Purpose: To identify the combined effect of increasing tissue level oxygen consumption and metabolite accumulation on the ergogenic efficacy of ischemic preconditioning (IPC) during both maximal aerobic and maximal anaerobic exercise. Methods: Twelve healthy males (22 ± 2 years, 179 ± 2 cm, 80 ± 10 kg, 48 ± 4 ml.kg−1.min−1) underwent four experimental conditions: (i) no IPC control, (ii) traditional IPC, (iii) IPC with EMS, and (iv) IPC with treadmill walking. IPC involved bilateral leg occlusion at 220 mmHg for 5 min, repeated three times, separated by 5 min of reperfusion. Within 10 min following the IPC procedures, a 30 s Wingate test and subsequent (after 25 min rest) incremental maximal aerobic test were performed on a cycle ergometer. Results: There was no statistical difference in anaerobic peak power between the no IPC control (1211 ± 290 W), traditional IPC (1209 ± 300 W), IPC + EMS (1206 ± 311 W), and IPC + Walk (1220 ± 288 W; P = 0.7); nor did VO2max change between no IPC control (48 ± 2 ml.kg−1.min−1), traditional IPC (48 ± 6 ml.kg−1.min−1), IPC + EMS (49 ± 4 ml.kg−1.min−1) and IPC + Walk (48 ± 6 ml.kg−1.min−1; P = 0.3). However, the maximal watts during the VO2max increased when IPC was combined with both EMS (304 ± 38 W) and walking (308 ± 40 W) compared to traditional IPC (296 ± 39 W) and no IPC control (293 ± 48 W; P = 0.02). Conclusion: This study shows that in a group of participants for whom a traditional IPC stimulus was not effective, the magnification of the IPC stress through muscle contractions while under occlusion led to a subsequent exercise performance response. These findings support that amplification of the ischemic preconditioning stimulus augments the effect for exercise capacity.
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Affiliation(s)
- Joshua T Slysz
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada
| | - Jamie F Burr
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON, Canada
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Girard O, Brocherie F, Millet GP. Effects of Altitude/Hypoxia on Single- and Multiple-Sprint Performance: A Comprehensive Review. Sports Med 2018; 47:1931-1949. [PMID: 28451905 DOI: 10.1007/s40279-017-0733-z] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Many sport competitions, typically involving the completion of single- (e.g. track-and-field or track cycling events) and multiple-sprint exercises (e.g. team and racquet sports, cycling races), are staged at terrestrial altitudes ranging from 1000 to 2500 m. Our aim was to comprehensively review the current knowledge on the responses to either acute or chronic altitude exposure relevant to single and multiple sprints. Performance of a single sprint is generally not negatively affected by acute exposure to simulated altitude (i.e. normobaric hypoxia) because an enhanced anaerobic energy release compensates for the reduced aerobic adenosine triphosphate production. Conversely, the reduction in air density in terrestrial altitude (i.e. hypobaric hypoxia) leads to an improved sprinting performance when aerodynamic drag is a limiting factor. With the repetition of maximal efforts, however, repeated-sprint ability is more altered (i.e. with earlier and larger performance decrements) at high altitudes (>3000-3600 m or inspired fraction of oxygen <14.4-13.3%) compared with either normoxia or low-to-moderate altitudes (<3000 m or inspired fraction of oxygen >14.4%). Traditionally, altitude training camps involve chronic exposure to low-to-moderate terrestrial altitudes (<3000 m or inspired fraction of oxygen >14.4%) for inducing haematological adaptations. However, beneficial effects on sprint performance after such altitude interventions are still debated. Recently, innovative 'live low-train high' methods, in isolation or in combination with hypoxic residence, have emerged with the belief that up-regulated non-haematological peripheral adaptations may further improve performance of multiple sprints compared with similar normoxic interventions.
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Affiliation(s)
- Olivier Girard
- Aspetar Orthopaedic and Sports Medicine Hospital, Athlete Health and Performance Research Centre, Doha, Qatar.
- ISSUL, Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland.
| | - Franck Brocherie
- Laboratory Sport, Expertise and Performance (EA 7370), Research Department, French Institute of Sport (INSEP), Paris, France
- ISSUL, Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
| | - Grégoire P Millet
- ISSUL, Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
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Christiansen D, Murphy RM, Bangsbo J, Stathis CG, Bishop DJ. Increased FXYD1 and PGC-1α mRNA after blood flow-restricted running is related to fibre type-specific AMPK signalling and oxidative stress in human muscle. Acta Physiol (Oxf) 2018; 223:e13045. [PMID: 29383885 PMCID: PMC5969286 DOI: 10.1111/apha.13045] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 01/01/2018] [Accepted: 01/24/2018] [Indexed: 12/24/2022]
Abstract
Aim This study explored the effects of blood flow restriction (BFR) on mRNA responses of PGC‐1α (total, 1α1, and 1α4) and Na+,K+‐ATPase isoforms (NKA; α1‐3, β1‐3, and FXYD1) to an interval running session and determined whether these effects were related to increased oxidative stress, hypoxia, and fibre type‐specific AMPK and CaMKII signalling, in human skeletal muscle. Methods In a randomized, crossover fashion, 8 healthy men (26 ± 5 year and 57.4 ± 6.3 mL kg−1 min−1) completed 3 exercise sessions: without (CON) or with blood flow restriction (BFR), or in systemic hypoxia (HYP, ~3250 m). A muscle sample was collected before (Pre) and after exercise (+0 hour, +3 hours) to quantify mRNA, indicators of oxidative stress (HSP27 protein in type I and II fibres, and catalase and HSP70 mRNA), metabolites, and α‐AMPK Thr172/α‐AMPK, ACC Ser221/ACC, CaMKII Thr287/CaMKII, and PLBSer16/PLB ratios in type I and II fibres. Results Muscle hypoxia (assessed by near‐infrared spectroscopy) was matched between BFR and HYP, which was higher than CON (~90% vs ~70%; P < .05). The mRNA levels of FXYD1 and PGC‐1α isoforms (1α1 and 1α4) increased in BFR only (P < .05) and were associated with increases in indicators of oxidative stress and type I fibre ACC Ser221/ACC ratio, but dissociated from muscle hypoxia, lactate, and CaMKII signalling. Conclusion Blood flow restriction augmented exercise‐induced increases in muscle FXYD1 and PGC‐1α mRNA in men. This effect was related to increased oxidative stress and fibre type‐dependent AMPK signalling, but unrelated to the severity of muscle hypoxia, lactate accumulation, and modulation of fibre type‐specific CaMKII signalling.
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Affiliation(s)
- D. Christiansen
- Institute of Sport, Exercise and Active Living (ISEAL); Victoria University; Melbourne Vic. Australia
| | - R. M. Murphy
- Department of Biochemistry and Genetics; La Trobe Institute for Molecular Science; La Trobe University; Melbourne Vic. Australia
| | - J. Bangsbo
- Department of Nutrition, Exercise and Sports (NEXS); University of Copenhagen; Copenhagen N Denmark
| | - C. G. Stathis
- Institute of Sport, Exercise and Active Living (ISEAL); Victoria University; Melbourne Vic. Australia
| | - D. J. Bishop
- Institute of Sport, Exercise and Active Living (ISEAL); Victoria University; Melbourne Vic. Australia
- School of Medical and Health Sciences; Edith Cowan University; Perth WA Australia
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Ferguson RA. Blood flow-restricted exercise: Providing more bang for buck in trained athletes? Acta Physiol (Oxf) 2018; 223:e13065. [PMID: 29575714 DOI: 10.1111/apha.13065] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Richard A Ferguson
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
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Bunevicius K, Grunovas A, Venckunas T, Poderiene K, Trinkunas E, Poderys J. Blood flow restriction late in recovery after heavy resistance exercise hampers muscle recuperation. Eur J Appl Physiol 2017; 118:313-320. [PMID: 29214460 DOI: 10.1007/s00421-017-3771-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2017] [Accepted: 11/23/2017] [Indexed: 11/25/2022]
Abstract
PURPOSE This study aimed to examine the effect of acute blood flow restriction during the late recovery phase between two resistance exercise bouts on muscular endurance and oxygenation. METHODS Amateur male middle- and long-distance runners performed two bouts of one-leg dynamic plantar flexion exercise to failure with the load equivalent to 75% of maximum. Subjects were randomly assigned into two experimental groups with thigh occlusion pressure between bouts at either 120 or 200 mmHg with 20 min of passive rest in between, and two control groups without any blood flow restriction separated by either 5 or 20 min of rest. Blood flow restriction in the experimental groups was implemented during the last 15 min of recovery. Calf arterial blood flow and muscle oxygenation were measured by venous occlusion plethysmography and near-infrared spectroscopy, respectively. RESULTS Decrease of muscular oxygenation and blood flow during recovery between exercise bouts depended on the applied occlusion pressure. When compared with bout 1, work capacity in the experimental groups during bout 2 was reduced by 9.3 ± 2.2% with 120 mmHg and by 10.5 ± 3.1% (p < 0.05) with 200 mmHg occlusion pressure. In the control groups, work capacity was restored after 20 min (- 3.9 ± 3.2%, p > 0.05) but not after 5-min recovery (- 20.0 ± 1.8%, p < 0.05). CONCLUSIONS Blood flow restriction late in recovery after a heavy resistance exercise bout decreased muscle oxygenation and work capacity during the subsequent heavy resistance exercise bout.
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Affiliation(s)
- Kestutis Bunevicius
- Institute of Sport Science and Innovations, Lithuanian Sports University, Sporto 6, 44221, Kaunas, Lithuania.
| | - Albinas Grunovas
- Institute of Sport Science and Innovations, Lithuanian Sports University, Sporto 6, 44221, Kaunas, Lithuania
| | - Tomas Venckunas
- Institute of Sport Science and Innovations, Lithuanian Sports University, Sporto 6, 44221, Kaunas, Lithuania
| | - Kristina Poderiene
- Institute of Sport Science and Innovations, Lithuanian Sports University, Sporto 6, 44221, Kaunas, Lithuania
| | - Eugenijus Trinkunas
- Institute of Sport Science and Innovations, Lithuanian Sports University, Sporto 6, 44221, Kaunas, Lithuania
| | - Jonas Poderys
- Institute of Sport Science and Innovations, Lithuanian Sports University, Sporto 6, 44221, Kaunas, Lithuania
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Conceição MS, Chacon-Mikahil MPT, Telles GD, Libardi CA, Júnior EMM, Vechin FC, DE Andrade ALL, Gáspari AF, Brum PC, Cavaglieri CR, Serag S, Spiegelman BM, Hawley JA, Camera DM. Attenuated PGC-1α Isoforms following Endurance Exercise with Blood Flow Restriction. Med Sci Sports Exerc 2017; 48:1699-707. [PMID: 27128665 DOI: 10.1249/mss.0000000000000970] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
INTRODUCTION Exercise performed with blood flow restriction simultaneously enhances the acute responses to both myogenic and mitochondrial pathways with roles in training adaptation. We investigated isoform-specific gene expression of the peroxisome proliferator-activated receptor gamma coactivator 1 and selected target genes and proteins regulating skeletal muscle training adaptation. METHODS Nine healthy, untrained males participated in a randomized, counterbalanced, crossover design in which each subject completed a bout of low-intensity endurance exercise performed with blood flow restriction (15 min cycling at 40% of V˙O2peak, BFR-EE), endurance exercise (30 min cycling at 70% of V˙O2peak, EE), or resistance exercise (4 × 10 repetitions of leg press at 70% of one-repetition maximum) separated by at least 1 wk of recovery. A single resting muscle biopsy (vastus lateralis) was obtained 2 wk before the first exercise trial (rest) and 3 h after each bout. RESULTS Total PGC-1α mRNA abundance, along with all four isoforms, increased above rest with EE only (P < 0.05) being higher than BFR-EE (P < 0.05). PGC-1α1, 2, and 4 were higher after EE compared with resistance exercise (P < 0.05). EE also increased vascular endothelial growth factor, Hif-1α, and MuRF-1 mRNA abundance above rest (P < 0.05), whereas COXIV mRNA expression increased with EE compared with BFR-EE (P < 0.05). CONCLUSION The attenuated expression of all four PGC-1α isoforms when EE is performed with blood flow restriction suggests this type of exercise provides an insufficient stimulus to activate the signaling pathways governing mitochondrial and angiogenesis responses observed with moderate- to high-intensity EE.
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Affiliation(s)
- Miguel Soares Conceição
- 1Faculty of Physical Education, University of Campinas, Campinas, BRAZIL; 2Laboratory of Neuromuscular Adaptations to Resistance Training, Department of Physical Education, Federal University of São Carlos, São Carlos, BRAZIL; 3School of Physical Education and Sport, University of São Paulo, São Paulo, BRAZIL; 4Department of Cell Biology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA; 5Mary MacKillop Institute for Health Research, Centre for Exercise and Nutrition, Australian Catholic University, Melbourne, AUSTRALIA; and 6Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, England, UNITED KINGDOM
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de Freitas MC, Gerosa-Neto J, Zanchi NE, Lira FS, Rossi FE. Role of metabolic stress for enhancing muscle adaptations: Practical applications. World J Methodol 2017; 7:46-54. [PMID: 28706859 PMCID: PMC5489423 DOI: 10.5662/wjm.v7.i2.46] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Accepted: 03/17/2017] [Indexed: 02/06/2023] Open
Abstract
Metabolic stress is a physiological process that occurs during exercise in response to low energy that leads to metabolite accumulation [lactate, phosphate inorganic (Pi) and ions of hydrogen (H+)] in muscle cells. Traditional exercise protocol (i.e., Resistance training) has an important impact on the increase of metabolite accumulation, which influences hormonal release, hypoxia, reactive oxygen species (ROS) production and cell swelling. Changes in acute exercise routines, such as intensity, volume and rest between sets, are determinants for the magnitude of metabolic stress, furthermore, different types of training, such as low-intensity resistance training plus blood flow restriction and high intensity interval training, could be used to maximize metabolic stress during exercise. Thus, the objective of this review is to describe practical applications that induce metabolic stress and the potential effects of metabolic stress to increase systemic hormonal release, hypoxia, ROS production, cell swelling and muscle adaptations.
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Allan R, Sharples AP, Close GL, Drust B, Shepherd SO, Dutton J, Morton JP, Gregson W. Postexercise cold water immersion modulates skeletal muscle PGC-1α mRNA expression in immersed and nonimmersed limbs: evidence of systemic regulation. J Appl Physiol (1985) 2017; 123:451-459. [PMID: 28546467 DOI: 10.1152/japplphysiol.00096.2017] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 04/07/2017] [Accepted: 05/23/2017] [Indexed: 11/22/2022] Open
Abstract
Mechanisms mediating postexercise cold-induced increases in PGC-1α gene expression in human skeletal muscle are yet to be fully elucidated but may involve local cooling effects on AMPK and p38 MAPK-related signaling and/or increased systemic β-adrenergic stimulation. Therefore, we aimed to examine whether postexercise cold water immersion enhancement of PGC-1α mRNA is mediated through local or systemic mechanisms. Ten subjects completed acute cycling (8 × 5 min at ~80% peak power output) followed by seated-rest (CON) or single-leg cold water immersion (CWI; 10 min, 8°C). Muscle biopsies were obtained preexercise, postexercise, and 3 h postexercise from a single limb in the CON condition but from both limbs in CWI [thereby providing tissue from a CWI and nonimmersed limb (NOT)]. Muscle temperature decreased up to 2 h postexercise following CWI (-5°C) in the immersed limb, with lesser changes observed in CON and NOT (-3°C, P < 0.05). No differences between limbs were observed in p38 MAPK phosphorylation at any time point (P < 0.05), whereas a significant interaction effect was present for AMPK phosphorylation (P = 0.031). Exercise (CON) increased gene expression of PGC-1α 3 h postexercise (~5-fold, P < 0.001). CWI augmented PGC-1α expression above CON in both the immersed (CWI; ~9-fold, P = 0.003) and NOT limbs (~12-fold, P = 0.001). Plasma normetanephrine concentration was higher in CWI vs. CON immediately postimmersion (860 vs. 665 pmol/l, P = 0.034). We report for the first time that local cooling of the immersed limb evokes transcriptional control of PGC-1α in the nonimmersed limb, suggesting increased systemic β-adrenergic activation of AMPK may mediate, in part, postexercise cold induction of PGC-1α mRNA.NEW & NOTEWORTHY We report for the first time that postexercise cold water immersion of one limb also enhances PGC-1α expression in a contralateral, nonimmersed limb. We suggest that increased systemic β-adrenergic stimulation, and not localized cooling per se, exerts regulatory effects on local signaling cascades, thereby modulating PGC-1α expression. Therefore, these data have important implications for research designs that adopt contralateral, nonimmersed limbs as a control condition while also increasing our understanding of the potential mechanisms underpinning cold-mediated PGC-1α responses.
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Affiliation(s)
- Robert Allan
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom; .,Centre for Applied Sport and Exercise Sciences, University of Central Lancashire, Preston United Kingdom
| | - Adam P Sharples
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Graeme L Close
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Barry Drust
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Sam O Shepherd
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - John Dutton
- Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich, United Kingdom; and
| | - James P Morton
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Warren Gregson
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
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Lloyd Jones MC, Morris MG, Jakeman JR. Impact of time and work:rest ratio matched sprint interval training programmes on performance: A randomised controlled trial. J Sci Med Sport 2017; 20:1034-1038. [PMID: 28410999 DOI: 10.1016/j.jsams.2017.03.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 02/16/2017] [Accepted: 03/23/2017] [Indexed: 12/18/2022]
Abstract
OBJECTIVES The aim of this study was to examine the effects of a short training intervention using two repeated sprint protocols matched for total sprint duration and work:rest ratio. DESIGN Randomised-controlled trial. METHODS Thirty physically active males were randomly allocated to one of two sprint training groups: a 6s group, a 30s group or a non-exercising control. The training groups were matched for work:rest ratio and total sprint time per session, and completed 6 training sessions over a 2-week period. Before and after the 2 week training period, participants completed a VO2max test and a 10km time trial on a cycle ergometer. RESULTS Time trial performance increased significantly by 5.1% in 6s (630±115s to 598±92s; p<0.05) and 6.2% in 30s (579±68s to 543±85s; p<0.05) from baseline testing, but there was no significant change in the control group (p>0.05), and no significant difference between exercise groups (p>0.05). The 6s group increased peak power output by 9.0% (from 1092±263W to 1181±248W; p<0.05) from sprint session 1 to 6, and the 30s group by 20.0% (1041±161W to 1237±159W; p<0.05). CONCLUSIONS This study indicates that both 6 and 30s bouts of repeated sprint exercise, matched for total sprint duration and W:R can improve athletic performance.
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Affiliation(s)
- Molly C Lloyd Jones
- Department of Sport and Health Sciences, Oxford Brookes University, United Kingdom
| | - Martyn G Morris
- Department of Sport and Health Sciences, Oxford Brookes University, United Kingdom; School of Life Sciences, Coventry University, United Kingdom
| | - John R Jakeman
- Department of Sport and Health Sciences, Oxford Brookes University, United Kingdom.
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Bonafiglia JT, Edgett BA, Baechler BL, Nelms MW, Simpson CA, Quadrilatero J, Gurd BJ. Acute upregulation of PGC-1α mRNA correlates with training-induced increases in SDH activity in human skeletal muscle. Appl Physiol Nutr Metab 2017; 42:656-666. [PMID: 28177701 DOI: 10.1139/apnm-2016-0463] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The purpose of the present study was to determine if acute responses in PGC-1α, VEGFA, SDHA, and GPD1-2 mRNA expression predict their associated chronic skeletal muscle molecular (SDH-GPD activity and substrate storage) and morphological (fibre-type composition and capillary density) adaptations following training. Skeletal muscle biopsies were collected from 14 recreationally active men (age: 22.0 ± 2.4 years) before (PRE) and 3 h after (3HR) the completion of an acute bout of sprint interval training (SIT) (eight 20-s intervals at ∼170% peak oxygen uptake work rate separated by 10 s of recovery). Participants then completed 6 weeks of SIT 4 times per week with additional biopsies after 2 (MID) and 6 (POST) weeks of training. Acute increases in PGC-1α mRNA strongly predicted increases in SDH activity (a marker of oxidative capacity) from PRE and MID to POST (PRE-POST: r = 0.81, r2 = 0.65, p < 0.01; MID-POST: r = 0.79, r2 = 0.62, p < 0.01) and glycogen content from MID to POST (r = 0.60, r2 = 0.36, p < 0.05). No other significant relationships were found between acute responses in PGC-1α, VEGFA, SDHA, and GPD1-2 mRNA expression and chronic adaptations to training. These results suggest that acute upregulation of PGC-1α mRNA relates to the magnitude of subsequent training-induced increases in oxidative capacity, but not other molecular and morphological chronic skeletal muscle adaptations. Additionally, acute mRNA responses in PGC-1α correlated with VEGFA, but not SDHA, suggesting a coordinated upregulation between PGC-1α and only some of its proposed targets in human skeletal muscle.
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Affiliation(s)
- Jacob T Bonafiglia
- a School of Kinesiology and Health Studies, Queen's University, Kingston, ON K7L 3N6 Canada
| | - Brittany A Edgett
- a School of Kinesiology and Health Studies, Queen's University, Kingston, ON K7L 3N6 Canada
| | - Brittany L Baechler
- c Department of Kinesiology, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Matthew W Nelms
- a School of Kinesiology and Health Studies, Queen's University, Kingston, ON K7L 3N6 Canada
| | - Craig A Simpson
- b Department of Emergency Medicine, Queen's University, Kingston, ON K7L 3N6, Canada
| | - Joe Quadrilatero
- c Department of Kinesiology, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Brendon J Gurd
- a School of Kinesiology and Health Studies, Queen's University, Kingston, ON K7L 3N6 Canada
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