Effect of training on fibre composition and phosphate metabolites in rest measured in vitro in muscles of young pigs

• Published in: Comparative biochemistry and physiology. B, Comparative biochemistry Vol. 102; no. 2; pp. 397 - 401
• Main Authors: Uhrín, Pavel, Liptaj, Tibor
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.06.1992; Elsevier Science
• Subjects: Analysis of Variance; Animals; Biological and medical sciences; Fundamental and applied biological sciences. Psychology; Magnetic Resonance Spectroscopy; Muscles - cytology; Muscles - metabolism; Phosphates - metabolism; Physical Conditioning, Animal; Rest; Space life sciences; Swine - metabolism; Vertebrates: body movement. Posture. Locomotion. Flight. Swimming. Physical exercise. Rest. Sports; Physical exercise; Phosphates; Physical training; Metabolite; Muscular fiber; Striated muscle; Pig; Vertebrata; Rest; Mammalia; Chemical composition; Artiodactyla; Ungulata
• ISSN: 0305-0491
• DOI: 10.1016/0305-0491(92)90141-D

1. 1. Fibre type composition and phosphate metabolites were studied in m. longissimus thoracis (MLT), m. rectus femoris (MRF) and m. triceps brachii (MTB) in trained ( N = 6) and sedentary ( N = 6) pigs. 2. 2. Samples were analyzed histochemically and by means of in vitro 31P NMR spectroscopy. 3. 3. Training (duration 11 weeks) consisted of treadmill running at a speed of 1.1 m/sec. The daily exercise time of trained animals gradually increased from 10 min during the very first days to 60 min at the end of the 4th week. 4. 4. During the final 7 weeks exercise time remained unchanged. Sedentary animals were not subjected to training. 5. 5. A higher proportion of type βR fibres in MRF, MTB and MLT and a lower proportion of type αW fibres were found in the trained group of animals compared to the control group. 6. 6. In MLT no significant differences in the proportion of type αW were observed between both groups. 7. 7. No significant differences in average fibre diameter of muscle fibres were found between groups. 8. 8. No differences in concentration of phosphate compounds were observed between trained and sedementary groups. 9. 9. Muscles with a higher proportion of type IIb fibres in both groups of pigs contained higher amounts of phosphocreatine (PCr) and were also characterized by a higher ratio of PCr to inorganic phosphate (P i).