Harder to Cool
When your body gets hot, it pumps more blood through your body in an attempt to cool itself. Once again, the slower-to-respond blood vessels aren’t helping. The process will take longer which leads to a higher heart rate and increased fatigue.
Lightheadedness After Stopping
Once you stop running, your muscles no longer need the high volume of oxygen-rich blood, so your heart slows down. But, since your blood vessels are slow to contract back, your blood pressure drops which can make you dizzy.
