TY - JOUR
T1 - Influence of exercise training on the oxidative capacity of rat abdominal muscles
AU - Uribe, J. M.
AU - Stump, C. S.
AU - Tipton, C. M.
AU - Fregosi, R. F.
N1 - Funding Information:
Acknowledgements. These studies were supported in part by National Institutes of Health Grants HL 41790 (R.F.F.) and HL 33 782 (C.M.T.). J.M. Uribe was supported by Grant IG 21690 from the American Heart Association-Arizona Affiliate. These studies represent partial fulfillment of his requirements for the Master of Science degree at The University of Arizona. C.S. Stump was supported by NASA Graduate Student Research Program Fe.l'owship G-50493.
PY - 1992
Y1 - 1992
N2 - Our purpose was to determine if endurance exercise training would increase the oxidative capacity of the abdominal expiratory muscles of the rat. Accordingly, 9 male rats were subjected to an endurance training protocol (1 h/day, 6 days/week, 9 weeks) and 9 litter-mates served as controls. Citrate synthase (CS) activity was used as an index of oxidative capacity, and was determined in the following muscles: soleus, plantaris, costal diaphragm, crural diaphragm, and in all four abdominal muscles: rectus abdominis, transversus abdominis, external oblique, and internal oblique. Compared to their non-trained litter-mates, the trained rats had higher peak whole body oxygen consumption rates (+16%) and CS activities in plantaris (+34%) and soleus (+36%) muscles. Thus, the training program caused substantial systemic and locomotor muscle adaptations. The CS activity of costal diaphragm was 20% greater in the trained animals, but no difference was observed in crural diaphragm. The CS activity in the abdominal muscles was less than one-half of that in locomotor and diaphragm muscles, and there were no significant changes with training except in the rectus abdominis where a 26% increase was observed. The increase in rectus abdominis CS pumping muscles adapted to the training protocol. The relatively low levels of CS activity in the abdominal muscles suggests that they are not recruited frequently at rest, and the lack of an increase with training indicates that these muscles do not contribute significantly to the increased ventilatory activity accompanying exercise in the rat.
AB - Our purpose was to determine if endurance exercise training would increase the oxidative capacity of the abdominal expiratory muscles of the rat. Accordingly, 9 male rats were subjected to an endurance training protocol (1 h/day, 6 days/week, 9 weeks) and 9 litter-mates served as controls. Citrate synthase (CS) activity was used as an index of oxidative capacity, and was determined in the following muscles: soleus, plantaris, costal diaphragm, crural diaphragm, and in all four abdominal muscles: rectus abdominis, transversus abdominis, external oblique, and internal oblique. Compared to their non-trained litter-mates, the trained rats had higher peak whole body oxygen consumption rates (+16%) and CS activities in plantaris (+34%) and soleus (+36%) muscles. Thus, the training program caused substantial systemic and locomotor muscle adaptations. The CS activity of costal diaphragm was 20% greater in the trained animals, but no difference was observed in crural diaphragm. The CS activity in the abdominal muscles was less than one-half of that in locomotor and diaphragm muscles, and there were no significant changes with training except in the rectus abdominis where a 26% increase was observed. The increase in rectus abdominis CS pumping muscles adapted to the training protocol. The relatively low levels of CS activity in the abdominal muscles suggests that they are not recruited frequently at rest, and the lack of an increase with training indicates that these muscles do not contribute significantly to the increased ventilatory activity accompanying exercise in the rat.
KW - Exercise
KW - Mammal
KW - O capacity (rat)
KW - Respiratory muscle
KW - Training
KW - endurance
KW - endurance training
KW - rat
KW - respiratory muscles (rat)
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U2 - 10.1016/0034-5687(92)90038-X
DO - 10.1016/0034-5687(92)90038-X
M3 - Article
C2 - 1626136
AN - SCOPUS:0026575926
VL - 88
SP - 171
EP - 180
JO - Respiratory Physiology and Neurobiology
JF - Respiratory Physiology and Neurobiology
SN - 1569-9048
IS - 1-2
ER -