Endurance training results inGroup of answer choicesmuscle atrophy.an increase in blood vessels to a muscle.muscle hypertrophy.an increase in muscle fibers.

Endurance training results in an increase in blood vessels to a muscle.

Here's why:

Endurance training, such as long-distance running or cycling, primarily improves the cardiovascular system, enhancing the body's ability to transport oxygen to the muscles. This is achieved by increasing the number of capillaries (small blood vessels) surrounding each muscle fiber. This increase in blood vessels allows for greater oxygen delivery to the muscles, which can improve endurance performance.

It's important to note that while endurance training can lead to some muscle hypertrophy (growth), this is not its primary effect. Similarly, it does not typically result in muscle atrophy (loss of muscle mass) unless the training is combined with inadequate nutrition or recovery. Finally, endurance training does not increase the number of muscle fibers, a process known as hyperplasia. This is more commonly associated with resistance or strength training.