What are the common signs that the lungs of the heart are trained as a result of exercise and physical labor?

When an untrained person begins to play sports, does physical exercise or just unusually hard work for him, the body does not have time to adapt to the stress. The body temperature rises, and the lungs do not have time to absorb enough oxygen, and this makes you dizzy. The heartbeat speeds up in order to have time to deliver oxygen to all parts of the body, but it is unusual for the heart to work at such speeds. And the muscles, without cooling, cause fatigue, so that a person would have a rest.