The soleus muscle in the calf, though only 1% of your body weight, can do big things to improve the metabolic health in the rest of your body if activated correctly. Researchers at the University of Houston are pioneering the “soleus pushup” which effectively elevates muscle metabolism for hours, even while you're sitting.
A soleus push up (SPU) consists of lifting the knee so that the foot makes a 30 degree angle while seated. Participants in the University of Houston research engaged in the activity for 270 minutes (4.5 hrs) without fatigue. This is due to the unique nature of the soleus muscle in that it does not deplete its stored glycogen during the SPU unlike other muscles which would during similar activities.
The soleus muscle is one of the two main muscles that form your calves (the other one being the gastrocnemius muscle which sits atop the soleus). The soleus stretches up from your Achilles tendon to the back of your knee, and is composed of "slow twitch" fibres. As well as allowing you to walk, run, or stand, the soleus has the critical task of constantly pumping blood back up to your heart.
Slow twitch type muscles can work for long periods before tiring out, as they don't require large amounts of energy because they use less stored sugar molecules (called glycogen) than type 2 fast twitch fibres do.
This research is still in its infancy, and the team says they're still working to develop the ideal way to do this move, but it's an easy leg movement you can do whenever you have to stay seated. Here's how they roughly described the soleus pushup:
- Sit in a chair with your knees hip-width apart. Relax your leg muscles and be sure both feet are flat on the floor.
- Next, raise both heels while keeping the front halves of your feet firmly planted on the floor.
- When your heels are as high as they can go, let them passively drop back down to the floor.
- Repeat this motion while you sit comfortably.
You can watch this video to see an example of the movement in this description of the study.
For more information, read the University of Houston press release: https://stories.uh.edu/2022-soleus-pu...
Read the full study published by Cell Press and made freely available by the National Library of Medicine: https://www.ncbi.nlm.nih.gov/pmc/arti...