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Does swimming minimize somatic and bone growth delay in rats?

The bone formation is regulated by hormonal factors and modified by extrinsic stimuli, such as practice of exercises. The effect of swimming on the somatic and bone growth of female rats subjected to two experimental models to reproduce hormone deficiency was assessed.Twenty-eight Wistar, neonate female rats separated in two groups: Monosodium glutamate (MGlu, n = 14; solution of monosodium glutamate 4.0mg/g, alternate days, first 14 days of life) and Saline Group (SAL, n = 14; saline solution. Body weight and measurements of somatic development (latero-lateral axis of the skull, anterior-posterior axis of the skull - LLS / APS - and length of the tail - LT) were evaluated from the 1st to the 30th day of life. At 60 days of life, the MGlu group was ovariectomized and SAL just went though surgical stress. Subsequently, half of the animals in each group started the swimming training (12 weeks, 5 days/week, 60 min/session), resulting in the following experimental groups: Sedentary saline (Sedsal, n = 7), Swimming saline (Swisal, n = 7), Sedentary glutamate ovariectomy (SedMGluO, n = 7) and Swimming glutamate ovariectomy (SwiMGluO, n = 7).At the end of the experiment, the right femur was weighed and its length assessed. At the 30 initial days, the MGlu group reduced its body weight and the LLS, APC and LT compared to SAL. At day 60, body weight of MGlu group remained lower and at the end of the experiment it was similar between Swisal and Sedsal groups; SedMGLuO and SwiMGluO groups. However, weight reduction was observed in SedMGlutO compared to SedSAL. Swimming helped the weight of the femur in the SAL and did not alter it between SedMGluO and SwiMGluO, but it increased in Sedsal compared to SedMGluO group. In length, the SwiSal was similar to Sedsal and the same situation occurred between SwiMGluO and SedMGluO. However, Sedsal group presented greater length than SedMGluO. Swimming was not able to reverse the effects caused by situations of body imbalance early induced in the bone tissue in young adult animals.

tissue; body growth; ovariectomy; swimming


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