Finding from a new study using 24-hour blood pressure monitoring confirm that physical activity reduces blood pressure in patients with high blood pressure, even when they are taking medications to address this problem.
After a exercise program, the average systolic & diastolic blood pressure falls down. 
Some ways to reduce Blood Pressure's are :
1.   Healthy eating can both reduce the risk of developing high blood pressure and lower blood pressure that is already elevated.
2.    Reduce the sodium (salt) in your diet.
3.    Achieve a healthy body weight.
4.    Increase foods that are high in potassium, magnesium and fibre.
5.    Increase foods that are high in calcium.
6.    Reduce caffeine and quit smoking.
Source : Times Network