Identify one specific substance necessary for muscle activity that is delivered to muscles more effectively as a result of increased heart rate

oxygen

Explanation:

Oxygen is the specific substance needed for muscle activity that is delivered to muscles most effectively as a result of increased heart rate.

The control of heart rate (HR) during rest and exercise is a good indicator of the level of intensity at which the heart is working and is an important information about a person's health status. The heart muscle will respond directly to the body's need for oxygen and blood flow at different times in life, both to perform an exercise of a certain level of intensity and during periods of illness or external need, in which the body responds by sending blood flow to the muscles and / or organs that require blood and O2 supply. Heart rate is an important part of different physiological variables. For example, cardiac output forms with the stroke volume. Heart rate is also part of the double product.

the gravitational force on an object increase as the mass of an object also, im not going to report you, but this question should be under the science category, not health

d, i believe because of it's activity level