Nasm Which muscles are typically underactive when the feet turn out
The Correct Answer and Explanation is :
When the feet turn out (a condition often referred to as foot external rotation), certain muscles may be underactive, meaning they are not functioning properly or are weak. The primary muscles that tend to be underactive in this situation are:
- Medial gastrocnemius: This muscle is part of the calf and helps control the rotation of the foot.
- Soleus: Also part of the calf, the soleus assists with stabilizing the ankle and controlling foot motion.
- Tibialis posterior: This muscle plays a key role in controlling the foot’s movement, particularly the inward rotation, and helps in stabilizing the arch of the foot.
- Gluteus medius: Although it’s primarily known for stabilizing the pelvis and controlling the hips, the gluteus medius also helps with proper foot alignment by influencing the rotation of the leg and ankle.
- Medial hamstrings: These muscles help stabilize the knee and control the rotation of the lower leg.
Explanation
Feet turning out during activities like walking, running, or standing (a condition sometimes called foot pronation or externally rotated feet) can be a sign of muscle imbalances or dysfunction in the kinetic chain. This means that certain muscles are not working as they should, leading to abnormal movement patterns.
The foot turning outward typically indicates underactive muscles that fail to stabilize or control the rotation of the lower leg and foot. The medial gastrocnemius and soleus are responsible for helping to control the foot’s movement, especially in terms of preventing excessive outward rotation. When they are weak, the foot may over-rotate outward. Similarly, the tibialis posterior, which helps maintain the alignment of the arch and controls the inward rotation of the foot, becomes underactive in this condition.
Gluteus medius and medial hamstrings play significant roles in stabilizing the pelvis and controlling lower limb alignment. Weakness in these muscles can affect the hip and knee’s ability to keep the foot in proper alignment during movement. This muscular imbalance often results from prolonged sitting, poor posture, or repetitive movement patterns, and it can lead to further issues like knee pain or low back discomfort if left unaddressed.
To correct this, strengthening these underactive muscles and addressing the alignment issues through corrective exercises can help restore proper movement mechanics and prevent further dysfunction.