After you read this posts, exercise will no longer be just exercise to you.


Because sports science is now sure that the type of exercise, how often your perform it, how long you perform it and at what intensity is now important no matter what workout you are doing.

When it comes to the benefits of exercise on your heart, early research is consistently showing that high-intensity interval training (HIIT) exercise has greater benefits for your heart than traditional, moderate-intensity exercise. In other words, exercising at 100% effort for a few seconds, followed by a few seconds of rest is superior to exercising at 60% intensity (per se)  for a number of minutes.

Intensity, Not Time Saves Your Heart

According to The American College of Sports Medicine, intensity, not time is most important for a healthy heart. In other words, working your heart at a high intensity every now and then is better than nothing at all. In fact, researchers designed a 16-year study to assess the effects of just one HIIT workout routine per week in comparison to people who did not exercise at all. In those who did perform a HIIT workout once per week had a significantly decreased risk of cardiovascular death. This study, and others like it, are profound in that they challenge recommendations that a certain duration of exercise per week is needed to maintain a healthy heart.

HIIT Effects on Heart Muscle and Oxygen Utilization

HIIT also has research-proven benefits in increasing muscle heart mass and utilization of oxygen in the body’s tissues. In this study, participants ran at 90-95% of their maximal heart rate four times for four minutes each bout. Results showed that this particular HIIT workout can increase the size of the major pumping heart muscles (left ventricle) by 12% and oxygen utility by 18%. Therefore, there is a positive relationship between exercise intensity and healthy heart muscle, as well as, oxygen utility. 

Now to The Rats: HIIT in the Lab

In taking an experimental approach in determining the effectiveness of HIIT, I will also present some of the changes in rat heart muscles that were noted with HIIT training.

  • Twice improved oxygen utility than moderate-intensity exercise
  • Improved force production of heart muscle.
  • Balanced, healthy enlargement of heart muscle
  • Increased volume of blood that the heart can hold

HIIT and the Human Heart in the Lab

We know that HIIT training is beneficial for the normal, healthy human heart. What about someone with heart failure?

Studies have not only shown that HIIT improves heart function in patients with heart failure, the researchers also boast that over 2000 hours of HIIT has been perform in their lab without any complications (Rognmo, O., unpublished manuscript/observations, 2009).

The Takeaway

If you are not incorporating HIIT training into your workout schedule at least once per week, you should strongly consider it. If it is medically safe for you to perform aerobic exercise, then it is likely safe (and more beneficial) for you to perform a HIIT workout. It’s pretty profound that even one HIIT workout routine per week can provide significant cardiovascular benefit. Take a few minutes during the week, get at least one HIIT done and your heart will love you for it!