Which factor could contribute to a patient's symptoms of weakness and shaking after receiving insulin?

The symptoms of weakness and shaking after receiving insulin are typically indicative of hypoglycemia, which occurs when blood glucose levels drop too low. Skipping a meal can lead to insufficient carbohydrate intake, which means there may not be enough glucose available in the bloodstream to counteract the effects of the insulin that has been administered. Insulin lowers blood glucose levels, and without accompanying carbohydrates from a meal to maintain those levels, a patient is more likely to experience symptoms of weakness and shaking as their body reacts to the inadequate glucose supply.

By avoiding a meal, the patient may have not replenished the glucose that insulin is causing to be utilized, thus leading to a drop in blood sugar levels and the presentation of these symptoms. In contrast, increased physical activity and increased carbohydrate intake would generally not lead to hypoglycemia in the same way if managed properly. Taking insulin later than scheduled could also result in fluctuations in blood sugar levels but is less directly linked to the specific symptoms after insulin administration compared to skipping a meal.