You do not need to be a hardcore athlete to boost your health heart.
Moderate exercise can significantly reduce your risk of heart disease and chronic illnesses as well as improve your endurance, strength and flexibility.
Though any aerobic exercise is good for your heart, these five physical activities are top notch for heart health.
1 Brisk walking
2 Running
3 Swimming
4 Cycling
5 Interval or Circuit training
If doing a solid stint of aerobic exercise  (1,2,3,4)  bores you to tears, mix up your cardio, for example: see this Interval programme.
This type of training will not only keep you motivated to exercise it will improve your muscular strength, endurance and Heart Health.