Final answer:
Endurance is the ability of the circulatory and respiratory systems to supply oxygen for dynamic physical activities, which is improved through aerobic exercises. Slow-twitch muscle fibers contribute significantly to endurance by carrying more oxygen, supported by the synergistic function of both circulatory and respiratory systems.
Step-by-step explanation:
The ability of the circulatory and respiratory systems to supply oxygen to the muscles to perform dynamic physical activity is known as endurance. This involves the body's capability to efficiently use oxygen to generate adenosine triphosphate (ATP), which is needed for muscle contractions during prolonged activities. Aerobic exercises, such as cycling and walking, are designed to improve this type of muscular endurance and cardiovascular health by increasing the heart rate and oxygen uptake.
In terms of ability to store oxygen and utilize it for aerobic respiration, slow-twitch muscle fibers are essential as they have more capillaries, mitochondria, and myoglobin. Endurance is associated with the increased capacity of these fibers to carry more oxygen and sustain activity for lengthier periods compared to fast-twitch fibers that are more suited to strength and power activities. The circulatory and respiratory systems work together synergistically to ensure that oxygen is transported from the lungs to the muscles, and carbon dioxide, the waste product, is removed efficiently.