Boushel 2015 Scand J Med Sci Sports

From Bioblast
Jump to: navigation, search
Publications in the MiPMap
Boushel R, Gnaiger E, Larsen FJ, Helge JW, Gonzalez-Alonso J, Ara I, Munch-Andersen T, van Hall G, Søndergaard H, Saltin B, Calbet JAL (2015) Maintained peak leg and pulmonary VO2 despite substantial reduction in muscle mitochondrial capacity. Scand J Med Sci Sports 25 (Suppl 4):135–43.

» PMID: 26589127 Open Access

Boushel R, Gnaiger E, Larsen FJ, Helge JW, Gonzalez-Alonso J, Ara I, Munch-Andersen T, van Hall G, Soendergaard H, Saltin B, Calbet JA (2015) Scand J Med Sci Sports

Abstract: We recently reported the circulatory and muscle oxidative capacities of the arm after prolonged low-intensity skiing in the arctic (Boushel et al., 2014). In the present study, leg VO2 was measured by the Fick method during leg cycling while muscle mitochondrial capacity was examined on a biopsy of the vastus lateralis in healthy volunteers (7 male, 2 female) before and after 42 days of skiing at 60% HR max. Peak pulmonary VO2 (3.52 ± 0.18 L.min-1 pre vs 3.52 ± 0.19 post) and VO2 across the leg (2.8 ± 0.4 L.min-1 pre vs 3.0 ± 0.2 post) were unchanged after the ski journey. Peak leg O2 delivery (3.6 ± 0.2 L.min-1 pre vs 3.8 ± 0.4 post), O2 extraction (82 ± 1% pre vs 83 ± 1 post), and muscle capillaries per mm2 (576 ± 17 pre vs 612 ± 28 post) were also unchanged; however, leg muscle mitochondrial OXPHOS capacity was reduced (90 ± 3 pmol.s-1.mg-1 pre vs 70 ± 2 post, P < 0.05) as was citrate synthase activity (40 ± 3 µmol.min-1.g-1 pre vs 34 ± 3; P < 0.05). These findings indicate that peak muscle VO2 can be sustained with a substantial reduction in mitochondrial OXPHOS capacity. This is achieved at a similar O2 delivery and a higher relative ADP-stimulated mitochondrial respiration at a higher mitochondrial p50. These findings support the concept that muscle mitochondrial respiration is submaximal at VO2max, and that mitochondrial volume can be downregulated by chronic energy demand.


Bioblast editor: Gnaiger E O2k-Network Lab: CA Vancouver Boushel RC, AT Innsbruck Gnaiger E, AT Innsbruck Oroboros, ES CN Las Palmas Calbet JA, SE Stockholm Larsen FJ


Labels: MiParea: Respiration, Exercise physiology;nutrition;life style 


Organism: Human  Tissue;cell: Skeletal muscle  Preparation: Intact organ, Permeabilized tissue 


Coupling state: OXPHOS  Pathway: F, N, S, NS  HRR: Oxygraph-2k 

MitoFitPublication, BMI, VO2max 

Science and adventure
Project of the Copenhagen Muscle Research Centre (CMRC), Rigshospitalet, Copenhagen, Denmark (Prof. Dr. Bengt Saltin). Logo of the CMRC Greenland 2004 Expedition, designed by Crownprince Frederik of Denmark.

Greenland expedition CMRC: science and adventure

» Greenland Expedition CMRC