A September 2022 study by the University of Houston on the soleus muscle in the calf and its development of  the “soleus pushup” (SPU) which effectively elevates muscle metabolism for hours, even when sitting.  The researchers said, 

  • “We never dreamed that this muscle has this type of capacity. It's been inside our bodies all along, but no one ever investigated how to use it to optimize our health, until now,” 

  • “When activated correctly, the soleus muscle can raise local oxidative metabolism to high levels for hours, not just minutes, and does so by using a different fuel mixture.”  

  • “The soleus’ lower-than-normal reliance on glycogen helps it work for hours effortlessly without fatiguing during this type of muscle activity, because there is a definite limit to muscular endurance caused by glycogen depletion,”

  •  “As far as we know, this is the first concerted effort to develop a specialized type of contractile activity centered around optimizing human metabolic processes.” 

Eureka notes

“The Soleus Pushup 

While seated with feet flat on the floor and muscles relaxed, the heel rises while the front of the foot stays put. When the heel gets to the top of its range of motion, the foot is passively released to come back down. The aim is to simultaneously shorten the calf muscle while the soleus is naturally activated by its motor neurons.”

The University of Houston added, 

  • “The soleus pushup looks simple from the outside, but sometimes what we see with our naked eye isn't the whole story. It’s a very specific movement that right now requires wearable technology and experience to optimize the health benefits,” 

  • “All of the 600 muscles combined normally contribute only about 15% of the whole-body oxidative metabolism in the three hours after ingesting carbohydrate. Despite the fact that the soleus is only 1% the body weight, it is capable of raising its metabolic rate during SPU contractions to easily double, even sometimes triple, the whole-body carbohydrate oxidation.” 

  • “We are unaware of any existing or promising pharmaceuticals that come close to raising and sustaining whole-body oxidative metabolism at this magnitude.”