Tired businesswoman sleeping on the desk, in front of the computer screen.Many individuals feel fatigued throughout the day even though they sleep well at night. One cause of fatigue is inadequate cardiac output.

Your heart (the cardiac muscle) provides oxygen and nutrients to all parts of the body through the pumping of blood. When cardiac output falls, tissues throughout the body, including your brain, your muscles, and other internal organs, are unable to metabolize at their normal rate.

A common cause of low cardiac output during the day is the pooling of body fluid into the legs when we are upright, either sitting or standing. This is a result of gravity continuously pulling the fluid downward away from the heart. This results is less fluid being returned to the heart and, as a direct result, cardiac output falls.

Cardiac output can be increased back to normal levels by making sure the pooled fluid in your lower body is being returned back to your heart. This is the role of your “secondary hearts” (the soleus muscles in calf of your legs). Lack of use leads to soleus insufficiency, but as with any muscle, the soleus muscles can be retrained, and cardiac output can be recovered.

Activities such as squatting exercises, Tai Chi, or other activities which require that you stand on your toes for long duration are good exercises for your soleus muscles. For those unable or not interested in undertaking such daily exercises, the HeartPartner has been developed as a means to passively exercise the soleus muscles. A couple of hours a day of HeartPartner use is sufficient to retrain your soleus muscles, resulting in a reduction of fluid pooling in the lower body and increased cardiac output.