A Abasspour Mojdehi; R Shabani; MR Fadaei chafy
Abstract
Aim: High intensitystrength and endurance training can increase exercise capacity. The aim of this study was to describe the effect of high intensity strength and endurance training on body fat index, glucose homeostasis and serum leptin of 15 to 20 year old Taekwondo players boy. Method: Of the eligible ...
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Aim: High intensitystrength and endurance training can increase exercise capacity. The aim of this study was to describe the effect of high intensity strength and endurance training on body fat index, glucose homeostasis and serum leptin of 15 to 20 year old Taekwondo players boy. Method: Of the eligible volunteers in the study, 20 taekwondo players aged 15 to 20 were selected as the research sample. The subjects were randomly divided into two groups: moderate-intensity resistance-endurance training (the first group, the mean age was 17.77 ± 2.26 years) and high intensity (second group, 16.90 ± 1.72 years). The first group, , had moderate intensity and endurance training for 95 minutes, and the second group performed high intensity training for 80 minutes. Along with the conventional taekwondo exercises Before and after 8 weeks training, body fat index, glucose hemeostasis and serum leptin were assessed. For data analysis, dependent t-test and independent t- test were used. p < strong>Results: Compared with the pre-test, in the second group a significant decrease was observed in the body fat percentage, insulin and insulin resistance levels. Leptin and FBS significantly decreased after exercise in both groups. The Comparison between groups showed only significant difference in body fat percentage (P=0.03).. Conclusion: High intensity strength and endurance training in athletes can potentially lead to significant reduction in subcutaneous fat. Decreased serum leptin and glucose levels and improved insulin sensitivity can improve the taekwondo lpayers performance
M Gholizadeh; F Rahmani nia; M SiahKuhian
Abstract
Aim: Most studies have used moderate or low intensity endurance exercise to examine the effect of food intake with high and low glycemic index on metabolic responses and oxidation of substrates. However, the effect of glycemic index on high intensity intermittent exercise, which is a major characteristic ...
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Aim: Most studies have used moderate or low intensity endurance exercise to examine the effect of food intake with high and low glycemic index on metabolic responses and oxidation of substrates. However, the effect of glycemic index on high intensity intermittent exercise, which is a major characteristic of many sports, has not been studied. The purpose of the present study was to investigate the effect of high-glycemic (HGI) and low-glycemic (LGI)index isoenergetic breakfast on glucose homeostasis and substrate oxidation during high intensity intermittent exercise (HIIE). Method: Eight male students with age 23.4 ± 0.9 years, weight 76/21± 4/38 kg, maximal oxygen uptake 53.7±1.0ml/kg/min, participated in two expermintal trials separated by 7 days. At each trial, 60 minutes after consumption isoenergitic breakfast (819 kcal), high intensity intermittent exercise (HIIE) was performed. Blood samples were evaluated for plasma glucose, insulin and glucagon, total fat and carbohydrate oxidation, evaluated by through respiratory equations. Results: The results showed that in the postprandial period, increase in plasma glucose concentrations in HGI (from 86 to 127mg/dl) (P <0.05). In HGI, glucose concentration decreases rapidly in the early period of HIIE (to 79 mg/dl), but remains almost stable in LGI (P <0.05). AUG of glucose and insulin in HGI were higher (1.08%) than LGI (1.37%), respectively. The oxidation of fat during activity in LGI (2.5 g) was higher than that of HGI (3 g) (p <0.05). Conclusion: HGI causes hyperglycemia and hyperinsulinemia in the postprandial period, and higher levels of insulin before exercise can lead to a sudden drop in blood glucose over the course of the activity, but LGI, due to lower insulinemia, helps to maintain better blood glucose and glucose homeostasis during HIIE. Keywords: Glycemic Index (GI), Glucose homeostasis, Substrate Oxidation, High Intensity Intermittent Exercise (HIIE)
