**8. Physical activity/exercise**

The physical activity comprises bodily movement fabricated by the tightening of skeletal muscles that requires energy expenditure in surplus of resting energy expenditure. Exercise is a subsection of physical activity: planned, structured, and repetitive bodily movement executed to improve or maintain one or more components of physical fitness.

Physical activity should be a vital part of the treatment plan for persons with diabetes. Exercise aids all persons with diabetes improve insulin sensitivity, diminishing cardiovascular risk factors, controlling body mass, and improving well-being.

In persons with T1DM, the glycemic response to exercise varies, contingent on overall diabetes control, plasma glucose, and insulin level at the start of exercise; timing, intensity, and duration of the exercise; previous food intake; and previous conditioning. A significant variable is the level of plasma insulin during and after exercise. Hypoglycemia can arise because of insulin-enhanced muscle glucose uptake by the exercising muscle.

Hypoglycemia is a possible problem associated with exercise in persons taking insulin or insulin secretagogues. Hypoglycemia can ensue during, immediately after, or many hours after exercise. This is because of increased insulin sensitivity after exercise and the need to supply liver and muscle glycogen, which can take up to 24 to 30 hours.

Hyperglycemia also can consequence from the exercise of high intensity, likely because of the effects of counterregulatory hormones. When a person exercises at what for him or her is a high level of exercise strength, there is a greater-than-normal increase in counterregulatory hormones. As a result, hepatic glucose release beats the rise in glucose use. The raised glucose level also may spread into the post-exercise state. Hyperglycemia and worsening ketosis also can consequence in persons with T1DM who are deprived of insulin for 12 to 48 hours and are ketotic. Vigorous activity should be escaped in the presence of ketosis [2]. It is not, however, necessary to delay exercise based simply on hyperglycemia, provided the individual senses well and urine and/or blood ketones are negative. High-intensity exercise is more likely to be the reason for hyperglycemia than insulin deficiency.
