The most common cause of vascular obstruction is a blood clot, also known as a DVT. This type of vascular problem usually occurs in one leg (not both), and leads to swelling of the soft tissues throughout the foot and ankle. The swelling can also extend further up the leg.
The hypothalamus is a part of your brain that controls body temperature. When you exercise, your body temperature increases, causing the hypothalamus to signal the brainstem to further increase your heart rate.
Heart rate reserve. Your heart beat rises during aerobic exercise. It can rise from 70 beats per minutes (bpm) at rest to as high as 170 bpm or even higher during exercise, depending on the intensity of the exercise, your fitness level, your age, and other factors.