Background & Aims: Type 1 diabetes is one of the most common endocrine disorders in children (5), which affects approximately 1 child under the age of 18 out of every 300 to 500 people (1). Time trend evaluation studies have shown that the prevalence of type 1 diabetes in childhood is increasing in all parts of the world, and the average relative increase is 3 to 4 percent per year. Also, the age of onset of type 1 diabetes in children has decreased. It is believed that non-genetic factors are important for the development of type 1 diabetes and its increase, but scientific evidence is insufficient and the causes of this increase and the current epidemic are still unknown (6). This disease is strongly related to microvascular and macrovascular complications, whose pathophysiological mechanisms are diverse and sometimes unclear (7, 8). Improving blood sugar control in diabetic patients leads to a reduction in the incidence of chronic complications of the disease and, of course, the cost of the resulting treatment (9). The main treatment in type 1 diabetes is the use of insulin, and an important part of nursing education in these patients includes education related to diabetes management regarding glycemic control in these children (9). Carrying out regular wind activities and an active lifestyle as a non-pharmacological intervention method is effective in promoting public health and also reducing the complications of some chronic diseases (10-12). One of the positive effects of regular exercise is improving carbohydrate metabolism in metabolic disorders, which can prevent complications related to hyperglycemia (13-15). Due to the high cost of treatment, non-pharmacological methods such as regular physical activity can play an important role in glycemic control and complications caused by diabetes in these people (5). In fact, type 1 diabetes is a challenging problem to manage various physiological and behavioral symptoms. Despite the importance of regular exercise in these people, it is very difficult to manage different methods of physical activity, especially for people with type 1 diabetes, and to provide health care in these people. People with type 1 diabetes, as a part of inactive people from the general population with an unhealthy physical index, are not very willing to participate in physical activity (16). One of the factors related to the low level of physical fitness and reluctance to participate in physical activities in these people is due to the fear of hypoglycemia (5). Although regular exercise can improve the health and well-being of children with type 1 diabetes; However, there are several barriers to exercise for a person with diabetes, including fear of hypoglycemia, loss of glycemic control, and inadequate knowledge about exercise therapy; Therefore, providing an exercise program in accordance with scientific sports recommendations as well as the needs related to motor development for these people can be beneficial (16). Considering the prevalence of type 1 diabetes and its irreversible complications, especially in younger children, as well as the importance of hyperglycemia control, it is important to reduce diabetic complications in these patients (8). Although exercise can be effective in improving the health of children with type 1 diabetes; But due to the difference in research results, more research is needed to prescribe a suitable exercise program for these people, which justifies the necessity of the present research; Therefore, the current research was designed with the aim of investigating the effect of selected combined exercises on glycemic control of girls with type 1 diabetes.
Methods: In quasi-experimental study 20 female patients with type 1 diabetes (age: 11.17 ± 2.60 years, height: 138.41 ± 12.10 cm, weighs: 32.24 ± 8.28 kg) using random sampling and they were divided into two training and control groups. Exercise training was done for eight weeks, three sessions per week and each session consisted of 60-90 minutes of combined training. Blood sampling was performed before and after the intervention period. Paired-samples t-tests were used to investigate within groups changes and independent t-tests were used to examine between groups.
Results: After the training period, the results a significant decrease in 2-Hour Plasma Glucose was observed in both exercise (P = 0.044) and control (P = 0.022) groups. There was also a significant decrease in fructosamine levels in the training group (P = 0.002). In the study of intergroup changes, fructosamine changes in the exercise group were significant compared to the control group (P = 0.038), but no difference was observed between level of fasting blood sugar (P = 0.201) and 2-Hour Plasma Glucose (P = 0.143) between exercise and control groups.
Conclusion: Regarding the relationship between physical activity and glycemic control in type 1 diabetes, it can be said that exercise in the training session can improve the sensitivity of insulin-sensitive cells such as muscle fibers like other people (27, 28); Admon et al showed in a study that a session of aerobic exercise can reduce blood glucose levels in patients with type 1 diabetes (29). In a meta-analysis, Burns et al stated that the combination of aerobic and resistance exercises can improve insulin sensitivity in children (30) and both types of exercises should be considered in designing exercises to improve insulin sensitivity. Among the effective mechanisms for improving insulin sensitivity after exercise, there are molecular mechanisms effective in insulin signaling, as well as a small increase in glucose membrane transporter-4 (GLUT4) after regular exercise in muscle cells, as well as an increase in GLUT4 accumulation. pointed out in the sarcoplasmic membrane (31-33). In this regard, Knudsen et al. showed that exercise increases GLUT4 in insulin-responsive storage vesicles and T tubules, and the accumulation of insulin-sensitive GLUT4 in sarcolemma and endosome membrane increases (34). Of course, in the present study, the level of muscle GLUT4 of the subjects was not checked due to the invasiveness of the muscle biopsy test, which is one of the limitations of the present study. Given that exercise can increase insulin sensitivity; In these people, during sports training and after training, it is necessary to consume smaller amounts of injectable insulin (5, 35). Considering that regular exercise can increase insulin sensitivity and reduce blood sugar levels during exercise as well as hours after exercise, in total, the cumulative effects of regular exercise along with drug treatment for patients with type 1 diabetes, It can prevent hyperglycemic damages such as glycosylation of proteins and cells of other body organs and prevent microvascular and macrovascular complications of diabetes in the long term (8, 36). Ghalavand et al showed in their research that regular exercise training increased insulin sensitivity and decreased 2-hour blood sugar (5). Although, in the present study, it was not possible to check glucose at different hours after exercise, and the fructosamine index was used as the average euglycemia of the subjects. Despite the positive benefits of fructosamine, including shorter life span and greater sensitivity to HbA1c and not being affected by factors related to hemoglobin changes, for a more accurate interpretation of fructosamine, it is necessary to check the amount of serum proteins (25), which was not measured in the present study. And it was one of the limitations of the present research. The findings of the present research showed that eight weeks of selected combined exercises improve glycemic control in the form of a decrease in serum fructosamine in girls with type 1 diabetes, and that exercise can play a positive role in the management of diabetes in these people.