Answer: A) Heart and lungs
Explanation:
The heart becomes more efficient with every beat as it pumps oxygen-carrying blood, the lungs more effective in taking in oxygen, and the muscles more equipped to use more oxygen.
Frequency is what the answer is. (How Frequent you exercise)
<span>By performing different stretching exercises targeting multiple areas, one is able to realize long-term flexibility. The exercises depend on the various target muscles and the intensity of the exercises determines the outcome. Moreover multiple muscle exercise like swimming have been noted to improve on flexibility.</span>
The skeletal system. Including bones and cartiladge.
