In some cultures in the Northern Hemisphere, the astronomical March equinox (varying between 19 and 21 March) is taken to mark the first day of spring, and the Northern solstice (around 21 June) is taken as the first day of summer. In other traditions, the equinox is taken as mid-spring.
Circulation problems that cause dizziness. You may feel dizzy, faint or off balance if your heart isn't pumping enough blood to your brain. Causes include: 1  Drop in blood pressure.
Heart disease health centre. Exercise and low blood pressure. If you have low blood pressure, some precautions may be needed before exercising. Some people with low blood pressure experience no symptoms at all, while others might have a brief sensation of feeling dizzy when standing up too quickly.