What is a good exercise to stretch the deep soleus muscle in my calves?

Here's how to do a standing soleus stretch:

Reps: 3-4
Sets: 1
Intensity: Light
Hold: 10-30 seconds
Rest: No rest needed

Starting position: Stand up straight in front of a wall with your arms extended at shoulder height.

Movement: Place your hands on the wall. Extend your right leg straight back and press the heel toward the floor. Let your left knee bend slightly as you do so, while keeping the heel grounded on the floor. Now bend your right knee as much as possible without lifting the heel off the floor. Hold. Return to the starting position. Finish all reps, then repeat with your left foot. This completes the set.

Tips and techniques:

• Stretch to the point of mild tension, not pain.
• Hold a full-body lean from the ankle as you stretch.
• Maintain neutral posture with your shoulders down and back.

Too hard? Hold the back of a chair and do not press as far into the stretch.

Too easy? Try to bend your back knee farther without lifting your heel off the floor. This increases the stretch.