Exercise's short-term impact on the cardiovascular system heart rate rise rise in stroke volume rise in cardiac output increase in total peripheral resistance fall in arterial pressure The short-term effects of exercise on the respiratory system include a rapid increase in respiration rate, deeper breathing, and increased blood oxygen content. The lungs also benefit from exercise by getting more air into them and therefore flushing out mucus and other debris. Exercise is also known to reduce the risk of developing chronic obstructive pulmonary disease (COPD). The short-term effects of exercise on the gastrointestinal system include increased digestion and absorption of food. The liver also benefits from exercise with increased blood flow causing it to release stored glycogen (blood sugar) for use by other parts of the body. The short-term effects of exercise on the immune system include increasing numbers of white blood cells which fight infection and improving how the body responds to infections. The short-term effects of exercise on the nervous system include improved brain function. When you exercise regularly your brain produces more dopamine which helps relieve depression. It also increases the amount of serotonin available to those who suffer from anxiety or panic attacks.