Our chances of developing type-2 diabetes are influenced by environmental factors such as the type of food we eat, the amount of exercise we do and getting older. Type 2 diabetes is a condition associated with the hormone insulin, either the body isn’t making enough of it or it isn’t working properly. Insulin is the signal that tells cells to remove glucose from the blood. If cells become less sensitive to insulin, they become much less effective at removing the glucose that is circulating in the blood. High blood sugar can eventually lead to problems with many different areas of the body such as damage to nerves, heart, eyes, kidneys and brain. Why does aging increase our risk of diabetes? As we age the body changes and so do biochemical processes occuring in our cells, such as proteins and their activity. One process that contributes to type-2 diabetes is GLUT-4 protein activity. The GLUT-4 protein is responsible for transporting glucose out of the blood and into the cells of the body. When insulin is released it will increase the uptake of glucose from the blood by telling these GLUT-4 proteins to transport more glucose into the cells. As we age, GLUT-4 activity reduces in many tissues and therefore when insulin is released into the blood after a meal, less glucose is being transported into the cells. Other mechanisms that increase the risk of getting this disease are muscle loss (sarcopenia) and sedentary lifestyles. As we age we begin to lose muscle mass, approximately 3–8% per decade after 30 years of age (brutal) and then it unfortunately accelerates after the age of 60. As skeletal muscle is one of the biggest consumers of cellular energy, it guzzles this glucose fuel from the bloodstream. Therefore, as we age and our muscle mass decreases we are not able to remove the same amount of sugar from the blood as we used to. Losing muscle mass will also make it harder for people to participate in day-to-day activities, resulting in fat accumulation which further increases the risk of diabetes. A single bout of exercise improves insulin sensitivity for up to two days after the activity has taken place. One of the mechanisms behind this increase in insulin sensitivity is thought to be improved GLUT-4 activity. Exercise stimulates movement of GLUT-4 proteins to the cell membrane, resulting in greater glucose uptake. This only occurs within the muscles that are used during that activity (another reason why it is important to exercise the whole body). Consistent exercise over time (months) will increase the abundance of these proteins existing on the cell membrane, making the insulin signal more effective, resulting in even greater glucose uptake. Exercise will also stimulate muscle growth, counteracting the loss caused by aging. The higher the muscle mass, the more glucose that will be consumed by muscles after eating a meal, lowering blood sugar. References DiMenna, F. J., & Arad, A. D. (2021). The acute vs. chronic effect of exercise on insulin sensitivity: Nothing lasts forever. Cardiovascular Endocrinology & Metabolism, 10(3), 149. Li, J., Li, J., & Lu, Y. (2021). Effects of resistance training on insulin sensitivity in the elderly: A meta-analysis of randomized controlled trials. Journal of Exercise Science & Fitness, 19(4), 241-251. Meiquer (2006). Insulin glucose metabolism. Online resource, accessed 07/01/24. File:Insulin glucose metabolism.jpg - Wikipedia Richter, E. A., Sylow, L., & Hargreaves, M. (2021). Interactions between insulin and exercise. Biochemical Journal, 478(21), 3827-3846. Sui, S. X., Williams, L. J., Holloway-Kew, K. L., Hyde, N. K., & Pasco, J. A. (2020). Skeletal muscle health and cognitive function: a narrative review. International journal of molecular sciences, 22(1), 255. Stocks, B., & Zierath, J. R. (2022). Post-translational Modifications: The Signals at the Intersection of Exercise, Glucose Uptake, and Insulin Sensitivity. Endocrine Reviews, 43(4), 654-677. Vargas, E., Podder, V., & Sepulveda, C. (2019). Physiology, glucose transporter type 4.
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Canterbury Strength Weightlifting Club
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