Why do athletes exercise harder or longer to achieve a maximum heart rate than a person not physically fit?

Answer 1

Actually, unless someone has heart failure, it is only partially due to how strong the heart muscle is. It also comes down to OXYGEN which is the fuel on which our bodies operate and BLOOD which carries the oxygen to our muscles and organs.

Here's a very simplified explanation:

Your body sets your pulse at a rate that will supply your body with enough fuel. The harder you work your muscles, the more fueld they need, and the faster your heart has to pump the blood to meet that need.

People with physically fit bodies are able to extract more oxygen for a given amount of blood. In order to do the same amount of work (such as running up a flight of stairs), a physically fit person does not have to increase their heart rate as much because their bodies are able to extract the necessary amount of oxygen from a smaller amount of blood.

If someone who is NOT as fit can only extract HALF the oxygen from the same amount of blood, for example, then their muscles will need to see twice as much blood to get the same amount of fuel. In order to get twice as much blood to their muscles in the same amount of time, their hearts must beat much harder and faster.

At the same time, aerobic training increases the amount of blood that can be ejected by the heart with each beat, meaning that your heart doesn't need to beat as frequently to supply the same amount of blood to the body. That makes TWO reasons why someone who is more fit needs a slower heart rate compared to someone who does not exercise.

By the same token, if someone has a heart that has been damaged by heart disease, they may not be able to push as much blood forward with each heartbeat. To do the same amount of work as someone with a healthy heart, they would need a much faster heart rate to make up for the weak squeeze of their heart.

Ultimately, athletes have to work their muscles MUCH HARDER before their heart rates reach the maximum, simply because their hearts don't have to pump as fast to keep the muscles well-supplied with oxygen.

Answer 2

think about it: the heart is a muscle.... people who lift weights develop their muscles so they can lift a greater maximum weight than those that dont... same with the heart it can take more "weight" before it hits its maximum.... I guess you can say its maximum is actually higher because it has become stronger.