Groundbreaking Discovery of “Special” Muscle That Can Promote Fat Burning While Sitting

The ‘Soleus Pushup’ is a metabolic innovation that rivals any therapeutic approach.

A groundbreaking discovery from the same mind whose research propelled the notion that “sitting too much is not the same as exercising too little” is poised to change a sedentary lifestyle: Even though just 1% of your body weight, the soleus muscle in the calf, if activated correctly, it can do great things to significantly improve metabolic health in the rest of your body.

And Marc Hamilton, Professor of Health and Human Performance at the University of Houston (UH), has discovered this approach to optimal activation. He pioneered the “soleus flex” (SPU) that effectively elevates muscle metabolism for hours, even while sitting. One of the 600 muscles in the human body, the soleus is a posterior muscle of the lower leg that extends from just below the knee to the heel.

Recently published in the magazine iScience, Hamilton’s research indicates that soleus flexing’s ability to maintain elevated oxidative metabolism to improve blood glucose regulation is more effective than any popular method currently touted as a solution. For example, soleus flexion is more effective at elevating oxidative metabolism than exercise, weight loss, and intermittent fasting. Oxidative metabolism is the process by which oxygen is used to burn metabolites such as blood glucose or fats. However, it depends, in part, on the immediate energy needs of the muscle when it is working.

“We never dreamed that this muscle has this kind of ability. It’s been inside our bodies all along, but no one has investigated how to use it to optimize our health, until now,” said Hamilton. “When properly activated, the soleus muscle can elevate local oxidative metabolism to high levels for hours, not just minutes, and it does so by using a different fuel mix.”

Muscle biopsies revealed that there was a minimal contribution of glycogen to fuel the soleus. Instead of breaking down glycogen, soleus can use other types of fuel, such as glucose and fats in the blood. Glycogen is normally the predominant type of carbohydrate that fuels muscle exertion.

“The lower-than-normal reliance of soleus on glycogen helps it work for hours effortlessly and without fatigue during this type of muscular activity, because there is a definite limit to muscular endurance caused by glycogen depletion,” he added. “To our knowledge, this is the first concerted effort to develop a specialized type of contractile activity focused on optimizing human metabolic processes.”

When SPU was tested, whole-body effects on blood chemistry included a 52% improvement in blood glucose (sugar) variation and 60% lower insulin requirements for three hours after ingesting a glucose drink.

The new approach of keeping soleus muscle metabolism going is also effective at doubling the normal rate of fat metabolism in the fasting period between meals, lowering blood fat levels (VLDL triglycerides).

soleus flexion

Building on years of research, Hamilton and his team developed the soleus pushup, which activates the soleus muscle differently than when standing or walking. The SPU targets the soleus to increase oxygen consumption, more than is possible with these other types of soleus activities, while also being resistant to fatigue.

So how do you perform a soleus flexion?

In short, while sitting with your feet flat on the ground and your muscles relaxed, your heel rises while the forefoot remains stationary. When the heel reaches the top of its range of motion, the foot passively releases to come back down. The goal is to simultaneously shorten the calf muscle while the soleus is naturally activated by its motor neurons.

While the SPU movement may look like walking (although it’s done sitting down), it’s actually the exact opposite, according to the researchers. When walking, the body is designed to minimize the amount of energy used, due to how the soleus moves. Hamilton’s method turns this on its head and makes the soleus use as much energy as possible over an extended period of time.

“The soleus flex looks simple from the outside, but sometimes what we see with the naked eye is not the whole story. It’s a very specific move that right now requires wearable technology and expertise to optimize the health benefits,” Hamilton said.

Additional publications are in the works focusing on how to teach people to learn this unique movement correctly, but without the sophisticated laboratory equipment used in this latest study.

This isn’t some new fitness tip or diet of the month, scientists are quick to point out. It is a powerful physiological movement that takes advantage of the unique characteristics of the soleus.

Possible first step towards a breakthrough in health care

Hamilton calls it the “most important study” ever completed in his Metabolic Innovations lab at UH and said the discovery could be a solution to a variety of health problems caused by spending hours every day living with a muscular metabolism. too low, caused by inactivity. . The average American sits around 10 hours a day.

Regardless of a person’s level of physical activity, spending too much time sitting has been shown to increase the risk of heart disease, diabetes, dementia and more. More than half of all American adults and 80% of people over the age of 65 are living with metabolic problems caused by diabetes or prediabetes.

Having a low metabolic rate while sitting is especially problematic for people who are at high risk for age-associated metabolic diseases, such as metabolic syndrome and type 2 diabetes.

Hamilton said that inactive muscles require less energy than most people seem to understand, calling it “one of the most fundamental, yet overlooked problems” leading the way to discovering metabolic solutions. to help prevent some chronic diseases associated with age.

“All 600 muscles combined normally contribute only about 15% of whole body oxidative metabolism in the three hours after carbohydrate ingestion. Even though soleus is only 1% of body weight, it is capable of increasing your metabolic rate during SPU contractions to easily double, sometimes even triple, your whole body’s carbohydrate oxidation.

We are not aware of any existing or promising drug that comes close to increasing and maintaining whole-body oxidative metabolism to this magnitude.”

Reference: “A Potent Physiologic Approach to Increase and Maintain Soleus Oxidative Metabolism Improves Glucose and Lipid Regulation” by Marc T. Hamilton, Deborah G.Hamilton, and Theodore W. Zderic, Aug 5, 2022, iScience.
DOI: 10.1016/j.isci.2022.104869