Which factors can enhance oxygen delivery to muscles during exercise?

Enhanced oxygen delivery to muscles during exercise is primarily influenced by increased cardiac output and improved blood flow. When you exercise, your working muscles require more oxygen to meet the higher energy demands. Cardiac output, which is the product of heart rate and stroke volume, rises significantly during exercise. This increase ensures that more blood—and thus more oxygen—can reach the muscles more efficiently.

Improved blood flow is also critical. As you exercise, vasodilation occurs in the working muscles, allowing for greater blood flow. This not only facilitates oxygen transport but also helps remove metabolic waste products like carbon dioxide and lactate, further promoting performance and endurance.

The other options do not promote improved oxygen delivery effectively. Increased body temperature and reduced heart rate do not correlate positively with better oxygen transport; in fact, a lower heart rate can reduce overall cardiac output. Decreased ventilation rates and lower cardiac output would lead to less oxygen being available for the muscles, while reduced blood volume and increased body weight would likely hinder rather than help oxygen transport and utilization during physical activity.