Please note, this article is written to expand a lay person’s knowledge of their body. The better you understand your body as an athlete, the better you will be able to look after it.
The soleus muscle lies behind the gastrocnemius muscle. Most people thinking of the calf will envisage the gastrocnemius muscle. If you stand on your tiptoes and look down at your calf, the two bulging areas on the upper part of your lower leg form the gastrocnemius muscle. Slide your hand to the bottom of those two bulges, and you get your soleus.
The muscle runs all the way from the bottom of the lower leg to the top and is covered by the gastrocnemius toward the top of the calf. Its origin is toward the top of both your tibia and fibula. and it inserts onto your calcaneus or heel bone. Its job is to plantar flex your foot. If you stand on your toes, particularly with your knees a bit bent you are using your soleus muscle. (Go for it, you know you want to give it a try).
Massage practitioners will at times bend your knee while massaging and then bend your foot upwards (toes toward knees) in order to better massage the muscle. A tight soleus might be a cause of posterior (rear) knee pain. (http://sbrsport.me/2014/02/28/sport-massage-at-sbr-sport/)
Two ways of stretching the muscle:
- Bend your knee, and with your heel on the floor, slowly move your knee forward.
- Rest the ball of your foot onto a raised platform , get your heel flat on the ground and slowly move your knee forward. (I prefer this stretch)
- Remember to warm up slowly.
- The muscle can get strained when forcefully pushing off from your foot. This would include speed work for runners, jumping, coming out of a deep squat etc.
- The muscle can also get strained during eccentric contractions. This includes the landing phase of a jump, and the landing of a runner who lands with their forefoot.
- Minimalistic shoes will put this area under more strain.
- The muscle can get strained from excessive pronation.
- Soleus tightness may be a hidden cause of back pain. (Travell & Simon 1992)
Hope this helps.