Aerobic capacity and skeletal muscle properties of normoxic and hypoxic rats in response to training
Abdelmalki, A. ; Fimbel, S. ; Mayet-Sornay, M. H. ; Sempore, B. ; Favier, R.
Springer
Published 1996
Springer
Published 1996
| ISSN: |
1432-2013
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| Keywords: |
Key words Capillarization ; Endurance time to exhaustion ; Fast-and slow-twitch skeletal muscles ; Fibre type distribution ; Food restriction ; Oxidative and glycolytic enzymes ; Maximal oxygen uptake
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| Source: |
Springer Online Journal Archives 1860-2000
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| Topics: |
Medicine
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| Notes: |
Abstract The aim of this study was to determine, in the rat, the effects of chronic exposure (7–9 weeks) to normobaric hypoxia (FIO2 = 0.13, equivalent to 3700 m altitude) on cardiac and skeletal muscle properties, on maximal oxygen uptake (VO2max), and endurance time to exhaustion (ETE). In addition, we evaluated the impact of endurance training (90 min of treadmill running per day, 5 days per week, for 9 weeks) on these parameters. The results were compared to normoxic rats fed ad libitum (NAL) and to normoxic pair-weight (NPW) animals in order to take into account the influence of hypoxia on growth rate. It was found that, in sedentary rats, hypoxia results in stunted growth, adrenal atrophy, a significant reduction of cross-sectional area of fast-twitch (type II) fibres, a reduced capillary-to-fibre ratio (C/F), and a reduced oxidative capacity (decreases in citrate synthase and 3-hydroxy-Acyl CoA dehydrogenase activities) of the plantaris muscle. These effects are mainly related to the anorexic effects of prolonged exposure to hypoxia. Nevertheless, hypoxic (H) rats displayed higher VO2max and ETE values when compared either to NAL or to NPW animals. Endurance training resulted, in all groups (H, NAL, NPW), in a significant change of the fibre type distribution of the plantaris which displayed an increased number of type IIA fibres and a decreased proportion of type IIB fibres. In addition, the C/F ratio and cross-sectional area of fast-twitch fibres were normalized by superimposition of training on hypoxia. Both VO2max and ETE were significantly higher in trained H rats than in NAL, but these improvements were mainly related to the reduced body weight induced by hypoxia. These data suggest that the greater aerobic capacity and tolerance for prolonged exercise induced by chronic exposure to hypoxia can be mainly accounted for by the anorexic effects of hypoxia, although other factors (e.g. increase in oxygen carrying capacity induced by hypoxia acclimatization) may play a significant role in some circumstances (e.g. in sedentary rats).
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| Type of Medium: |
Electronic Resource
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| URL: |
| _version_ | 1798295877590188032 |
|---|---|
| autor | Abdelmalki, A. Fimbel, S. Mayet-Sornay, M. H. Sempore, B. Favier, R. |
| autorsonst | Abdelmalki, A. Fimbel, S. Mayet-Sornay, M. H. Sempore, B. Favier, R. |
| book_url | http://dx.doi.org/10.1007/s004240050051 |
| datenlieferant | nat_lic_papers |
| hauptsatz | hsatz_simple |
| identnr | NLM201007258 |
| issn | 1432-2013 |
| journal_name | Pflügers Archiv |
| materialart | 1 |
| notes | Abstract The aim of this study was to determine, in the rat, the effects of chronic exposure (7–9 weeks) to normobaric hypoxia (FIO2 = 0.13, equivalent to 3700 m altitude) on cardiac and skeletal muscle properties, on maximal oxygen uptake (VO2max), and endurance time to exhaustion (ETE). In addition, we evaluated the impact of endurance training (90 min of treadmill running per day, 5 days per week, for 9 weeks) on these parameters. The results were compared to normoxic rats fed ad libitum (NAL) and to normoxic pair-weight (NPW) animals in order to take into account the influence of hypoxia on growth rate. It was found that, in sedentary rats, hypoxia results in stunted growth, adrenal atrophy, a significant reduction of cross-sectional area of fast-twitch (type II) fibres, a reduced capillary-to-fibre ratio (C/F), and a reduced oxidative capacity (decreases in citrate synthase and 3-hydroxy-Acyl CoA dehydrogenase activities) of the plantaris muscle. These effects are mainly related to the anorexic effects of prolonged exposure to hypoxia. Nevertheless, hypoxic (H) rats displayed higher VO2max and ETE values when compared either to NAL or to NPW animals. Endurance training resulted, in all groups (H, NAL, NPW), in a significant change of the fibre type distribution of the plantaris which displayed an increased number of type IIA fibres and a decreased proportion of type IIB fibres. In addition, the C/F ratio and cross-sectional area of fast-twitch fibres were normalized by superimposition of training on hypoxia. Both VO2max and ETE were significantly higher in trained H rats than in NAL, but these improvements were mainly related to the reduced body weight induced by hypoxia. These data suggest that the greater aerobic capacity and tolerance for prolonged exercise induced by chronic exposure to hypoxia can be mainly accounted for by the anorexic effects of hypoxia, although other factors (e.g. increase in oxygen carrying capacity induced by hypoxia acclimatization) may play a significant role in some circumstances (e.g. in sedentary rats). |
| package_name | Springer |
| publikationsjahr_anzeige | 1996 |
| publikationsjahr_facette | 1996 |
| publikationsjahr_intervall | 8004:1995-1999 |
| publikationsjahr_sort | 1996 |
| publisher | Springer |
| reference | 431 (1996), S. 671-679 |
| schlagwort | Key words Capillarization Endurance time to exhaustion Fast-and slow-twitch skeletal muscles Fibre type distribution Food restriction Oxidative and glycolytic enzymes Maximal oxygen uptake |
| search_space | articles |
| shingle_author_1 | Abdelmalki, A. Fimbel, S. Mayet-Sornay, M. H. Sempore, B. Favier, R. |
| shingle_author_2 | Abdelmalki, A. Fimbel, S. Mayet-Sornay, M. H. Sempore, B. Favier, R. |
| shingle_author_3 | Abdelmalki, A. Fimbel, S. Mayet-Sornay, M. H. Sempore, B. Favier, R. |
| shingle_author_4 | Abdelmalki, A. Fimbel, S. Mayet-Sornay, M. H. Sempore, B. Favier, R. |
| shingle_catch_all_1 | Abdelmalki, A. Fimbel, S. Mayet-Sornay, M. H. Sempore, B. Favier, R. Aerobic capacity and skeletal muscle properties of normoxic and hypoxic rats in response to training Key words Capillarization Endurance time to exhaustion Fast-and slow-twitch skeletal muscles Fibre type distribution Food restriction Oxidative and glycolytic enzymes Maximal oxygen uptake Key words Capillarization Endurance time to exhaustion Fast-and slow-twitch skeletal muscles Fibre type distribution Food restriction Oxidative and glycolytic enzymes Maximal oxygen uptake Abstract The aim of this study was to determine, in the rat, the effects of chronic exposure (7–9 weeks) to normobaric hypoxia (FIO2 = 0.13, equivalent to 3700 m altitude) on cardiac and skeletal muscle properties, on maximal oxygen uptake (VO2max), and endurance time to exhaustion (ETE). In addition, we evaluated the impact of endurance training (90 min of treadmill running per day, 5 days per week, for 9 weeks) on these parameters. The results were compared to normoxic rats fed ad libitum (NAL) and to normoxic pair-weight (NPW) animals in order to take into account the influence of hypoxia on growth rate. It was found that, in sedentary rats, hypoxia results in stunted growth, adrenal atrophy, a significant reduction of cross-sectional area of fast-twitch (type II) fibres, a reduced capillary-to-fibre ratio (C/F), and a reduced oxidative capacity (decreases in citrate synthase and 3-hydroxy-Acyl CoA dehydrogenase activities) of the plantaris muscle. These effects are mainly related to the anorexic effects of prolonged exposure to hypoxia. Nevertheless, hypoxic (H) rats displayed higher VO2max and ETE values when compared either to NAL or to NPW animals. Endurance training resulted, in all groups (H, NAL, NPW), in a significant change of the fibre type distribution of the plantaris which displayed an increased number of type IIA fibres and a decreased proportion of type IIB fibres. In addition, the C/F ratio and cross-sectional area of fast-twitch fibres were normalized by superimposition of training on hypoxia. Both VO2max and ETE were significantly higher in trained H rats than in NAL, but these improvements were mainly related to the reduced body weight induced by hypoxia. These data suggest that the greater aerobic capacity and tolerance for prolonged exercise induced by chronic exposure to hypoxia can be mainly accounted for by the anorexic effects of hypoxia, although other factors (e.g. increase in oxygen carrying capacity induced by hypoxia acclimatization) may play a significant role in some circumstances (e.g. in sedentary rats). 1432-2013 14322013 Springer |
| shingle_catch_all_2 | Abdelmalki, A. Fimbel, S. Mayet-Sornay, M. H. Sempore, B. Favier, R. Aerobic capacity and skeletal muscle properties of normoxic and hypoxic rats in response to training Key words Capillarization Endurance time to exhaustion Fast-and slow-twitch skeletal muscles Fibre type distribution Food restriction Oxidative and glycolytic enzymes Maximal oxygen uptake Key words Capillarization Endurance time to exhaustion Fast-and slow-twitch skeletal muscles Fibre type distribution Food restriction Oxidative and glycolytic enzymes Maximal oxygen uptake Abstract The aim of this study was to determine, in the rat, the effects of chronic exposure (7–9 weeks) to normobaric hypoxia (FIO2 = 0.13, equivalent to 3700 m altitude) on cardiac and skeletal muscle properties, on maximal oxygen uptake (VO2max), and endurance time to exhaustion (ETE). In addition, we evaluated the impact of endurance training (90 min of treadmill running per day, 5 days per week, for 9 weeks) on these parameters. The results were compared to normoxic rats fed ad libitum (NAL) and to normoxic pair-weight (NPW) animals in order to take into account the influence of hypoxia on growth rate. It was found that, in sedentary rats, hypoxia results in stunted growth, adrenal atrophy, a significant reduction of cross-sectional area of fast-twitch (type II) fibres, a reduced capillary-to-fibre ratio (C/F), and a reduced oxidative capacity (decreases in citrate synthase and 3-hydroxy-Acyl CoA dehydrogenase activities) of the plantaris muscle. These effects are mainly related to the anorexic effects of prolonged exposure to hypoxia. Nevertheless, hypoxic (H) rats displayed higher VO2max and ETE values when compared either to NAL or to NPW animals. Endurance training resulted, in all groups (H, NAL, NPW), in a significant change of the fibre type distribution of the plantaris which displayed an increased number of type IIA fibres and a decreased proportion of type IIB fibres. In addition, the C/F ratio and cross-sectional area of fast-twitch fibres were normalized by superimposition of training on hypoxia. Both VO2max and ETE were significantly higher in trained H rats than in NAL, but these improvements were mainly related to the reduced body weight induced by hypoxia. These data suggest that the greater aerobic capacity and tolerance for prolonged exercise induced by chronic exposure to hypoxia can be mainly accounted for by the anorexic effects of hypoxia, although other factors (e.g. increase in oxygen carrying capacity induced by hypoxia acclimatization) may play a significant role in some circumstances (e.g. in sedentary rats). 1432-2013 14322013 Springer |
| shingle_catch_all_3 | Abdelmalki, A. Fimbel, S. Mayet-Sornay, M. H. Sempore, B. Favier, R. Aerobic capacity and skeletal muscle properties of normoxic and hypoxic rats in response to training Key words Capillarization Endurance time to exhaustion Fast-and slow-twitch skeletal muscles Fibre type distribution Food restriction Oxidative and glycolytic enzymes Maximal oxygen uptake Key words Capillarization Endurance time to exhaustion Fast-and slow-twitch skeletal muscles Fibre type distribution Food restriction Oxidative and glycolytic enzymes Maximal oxygen uptake Abstract The aim of this study was to determine, in the rat, the effects of chronic exposure (7–9 weeks) to normobaric hypoxia (FIO2 = 0.13, equivalent to 3700 m altitude) on cardiac and skeletal muscle properties, on maximal oxygen uptake (VO2max), and endurance time to exhaustion (ETE). In addition, we evaluated the impact of endurance training (90 min of treadmill running per day, 5 days per week, for 9 weeks) on these parameters. The results were compared to normoxic rats fed ad libitum (NAL) and to normoxic pair-weight (NPW) animals in order to take into account the influence of hypoxia on growth rate. It was found that, in sedentary rats, hypoxia results in stunted growth, adrenal atrophy, a significant reduction of cross-sectional area of fast-twitch (type II) fibres, a reduced capillary-to-fibre ratio (C/F), and a reduced oxidative capacity (decreases in citrate synthase and 3-hydroxy-Acyl CoA dehydrogenase activities) of the plantaris muscle. These effects are mainly related to the anorexic effects of prolonged exposure to hypoxia. Nevertheless, hypoxic (H) rats displayed higher VO2max and ETE values when compared either to NAL or to NPW animals. Endurance training resulted, in all groups (H, NAL, NPW), in a significant change of the fibre type distribution of the plantaris which displayed an increased number of type IIA fibres and a decreased proportion of type IIB fibres. In addition, the C/F ratio and cross-sectional area of fast-twitch fibres were normalized by superimposition of training on hypoxia. Both VO2max and ETE were significantly higher in trained H rats than in NAL, but these improvements were mainly related to the reduced body weight induced by hypoxia. These data suggest that the greater aerobic capacity and tolerance for prolonged exercise induced by chronic exposure to hypoxia can be mainly accounted for by the anorexic effects of hypoxia, although other factors (e.g. increase in oxygen carrying capacity induced by hypoxia acclimatization) may play a significant role in some circumstances (e.g. in sedentary rats). 1432-2013 14322013 Springer |
| shingle_catch_all_4 | Abdelmalki, A. Fimbel, S. Mayet-Sornay, M. H. Sempore, B. Favier, R. Aerobic capacity and skeletal muscle properties of normoxic and hypoxic rats in response to training Key words Capillarization Endurance time to exhaustion Fast-and slow-twitch skeletal muscles Fibre type distribution Food restriction Oxidative and glycolytic enzymes Maximal oxygen uptake Key words Capillarization Endurance time to exhaustion Fast-and slow-twitch skeletal muscles Fibre type distribution Food restriction Oxidative and glycolytic enzymes Maximal oxygen uptake Abstract The aim of this study was to determine, in the rat, the effects of chronic exposure (7–9 weeks) to normobaric hypoxia (FIO2 = 0.13, equivalent to 3700 m altitude) on cardiac and skeletal muscle properties, on maximal oxygen uptake (VO2max), and endurance time to exhaustion (ETE). In addition, we evaluated the impact of endurance training (90 min of treadmill running per day, 5 days per week, for 9 weeks) on these parameters. The results were compared to normoxic rats fed ad libitum (NAL) and to normoxic pair-weight (NPW) animals in order to take into account the influence of hypoxia on growth rate. It was found that, in sedentary rats, hypoxia results in stunted growth, adrenal atrophy, a significant reduction of cross-sectional area of fast-twitch (type II) fibres, a reduced capillary-to-fibre ratio (C/F), and a reduced oxidative capacity (decreases in citrate synthase and 3-hydroxy-Acyl CoA dehydrogenase activities) of the plantaris muscle. These effects are mainly related to the anorexic effects of prolonged exposure to hypoxia. Nevertheless, hypoxic (H) rats displayed higher VO2max and ETE values when compared either to NAL or to NPW animals. Endurance training resulted, in all groups (H, NAL, NPW), in a significant change of the fibre type distribution of the plantaris which displayed an increased number of type IIA fibres and a decreased proportion of type IIB fibres. In addition, the C/F ratio and cross-sectional area of fast-twitch fibres were normalized by superimposition of training on hypoxia. Both VO2max and ETE were significantly higher in trained H rats than in NAL, but these improvements were mainly related to the reduced body weight induced by hypoxia. These data suggest that the greater aerobic capacity and tolerance for prolonged exercise induced by chronic exposure to hypoxia can be mainly accounted for by the anorexic effects of hypoxia, although other factors (e.g. increase in oxygen carrying capacity induced by hypoxia acclimatization) may play a significant role in some circumstances (e.g. in sedentary rats). 1432-2013 14322013 Springer |
| shingle_title_1 | Aerobic capacity and skeletal muscle properties of normoxic and hypoxic rats in response to training |
| shingle_title_2 | Aerobic capacity and skeletal muscle properties of normoxic and hypoxic rats in response to training |
| shingle_title_3 | Aerobic capacity and skeletal muscle properties of normoxic and hypoxic rats in response to training |
| shingle_title_4 | Aerobic capacity and skeletal muscle properties of normoxic and hypoxic rats in response to training |
| sigel_instance_filter | dkfz geomar wilbert ipn albert fhp |
| source_archive | Springer Online Journal Archives 1860-2000 |
| timestamp | 2024-05-06T09:43:11.388Z |
| titel | Aerobic capacity and skeletal muscle properties of normoxic and hypoxic rats in response to training |
| titel_suche | Aerobic capacity and skeletal muscle properties of normoxic and hypoxic rats in response to training |
| topic | WW-YZ |
| uid | nat_lic_papers_NLM201007258 |