title: Exercise duration-matched interval and continuous sprint cycling induce similar increases in AMPK phosphorylation, PGC-1α and VEGF mRNA expression in trained individuals.
abstract: OBJECTIVE
  The effects of low-volume interval and continuous 'all-out' cycling, matched for total exercise duration, on mitochondrial and angiogenic cell signalling was investigated in trained individuals.
  
  
  METHODS
  In a repeated measures design, 8 trained males ([Formula: see text], 57 ± 7 ml kg(-1) min(-1)) performed two cycling exercise protocols; interval (INT, 4 × 30 s maximal sprints interspersed by 4 min passive recovery) or continuous (CON, 2 min continuous maximal sprint). Muscle biopsies were obtained before, immediately after and 3 h post-exercise.
  
  
  RESULTS
  Total work was 53 % greater (P = 0.01) in INT compared to CON (71.2 ± 7.3 vs. 46.3 ± 2.7 kJ, respectively). Phosphorylation of AMPK(Thr172) increased by a similar magnitude (P = 0.347) immediately post INT and CON (1.6 ± 0.2 and 1.3 ± 0.3 fold, respectively; P = 0.011), before returning to resting values at 3 h post-exercise. mRNA expression of PGC-1α (7.1 ± 2.1 vs. 5.5 ± 1.8 fold; P = 0.007), VEGF (3.5 ± 1.2 vs. 4.3 ± 1.8 fold; P = 0.02) and HIF-1α (2.0 ± 0.5 vs. 1.5 ± 0.3 fold; P = 0.04) increased at 3 h post-exercise in response to INT and CON, respectively; the magnitude of which were not different between protocols.
  
  
  CONCLUSIONS
  Despite differences in total work done, low-volume INT and CON 'all-out' cycling, matched for exercise duration, provides a similar stimulus for the induction of mitochondrial and angiogenic cell signalling pathways in trained skeletal muscle.
authors.affiliation: School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, Leicestershire, LE11 3TU, UK.|English Institute of Sport, EIS Performance Centre, Loughborough University, Loughborough, LE11 3TU, UK.|English Institute of Sport, Manchester Institute of Health and Performance, 299 Alan Turing Way, Manchester, M11 3BS, UK.
authors.forename: Conor W
authors.initials: CW
authors.lastname: Taylor
authors.affiliation: English Institute of Sport, EIS Performance Centre, Loughborough University, Loughborough, LE11 3TU, UK.
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Ingham
authors.affiliation: School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, Leicestershire, LE11 3TU, UK.|Faculty of Health and Medical Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, GU2 7YW, UK.
authors.forename: Julie E A
authors.initials: JE
authors.lastname: Hunt
authors.affiliation: School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, Leicestershire, LE11 3TU, UK.
authors.forename: Neil R W
authors.initials: NR
authors.lastname: Martin
authors.affiliation: English Institute of Sport, EIS Performance Centre, Loughborough University, Loughborough, LE11 3TU, UK.|British Athletics, National Performance Institute, Loughborough University, Loughborough, LE11 3TU, UK.
authors.forename: Jamie S M
authors.initials: JS
authors.lastname: Pringle
authors.affiliation: School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, Leicestershire, LE11 3TU, UK. R.Ferguson@lboro.ac.uk.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Ferguson
mesh_terms: D055372:AMP-Activated Protein Kinases / Q000378:metabolism; D000328:Adult; D042501:Angiogenic Proteins / Q000378:metabolism; D001642:Bicycling / Q000502:physiology*; D018592:Cross-Over Studies; D006801:Humans; D008297:Male; D008928:Mitochondria / Q000502:physiology*; D018919:Neovascularization, Physiologic / Q000502:physiology*; D001678:Organelle Biogenesis; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha / Q000378:metabolism; D010766:Phosphorylation; D005082:Physical Exertion / Q000502:physiology*; D052097:Quadriceps Muscle / Q000098:blood supply / Q000502:physiology*; D016896:Treatment Outcome; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism*
chemical_list: D042501:Angiogenic Proteins; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D055372:AMP-Activated Protein Kinases
keywords: Angiogenesis; HIF-1α; High-intensity training; Mitochondrial biogenesis; Sprint interval exercise