Discovery Unlocks Potential of ‘Special’ Muscle

soleus flexion

Building on years of research, Hamilton and colleagues developed the soleus push-up, 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 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 instruct people to properly learn this unique movement, but without the sophisticated laboratory equipment used in this latest study.

The researchers are quick to point out that this is not a new fitness tip or diet of the month. It is a powerful physiological movement that takes advantage of the unique characteristics of the soleus.