The flexor digitorum longus is a long, narrow muscle that is found in the lower leg. This muscle plantar flexes and inverts the foot, flexes the toes and helps the foot "grip" the ground. Target this muscle with flexor digitorum longus strengthening exercises.
Keeping this muscle strong and conditioned will help exercise-related and overuse injuries of the posterior leg. Perform 10 repetitions of each exercise, working up to three sets in a row.
Read more: Foot Exercises for Metatarsal Pain
1. Foot Inversion
- Inversion of the foot occurs when the sole of the foot is turned medially.
- Sit on the floor with your legs extended to the front.
- Slowly rotate your right foot so that the sole faces toward your left foot.
- Hold this position for five seconds; then place your foot flat on the floor.
- Repeat the exercise with your left foot.
Increase the difficulty of this exercise by looping a resistance band around the ball of the working foot. Keep the outside of the band pulled tight to add resistance to the exercise.
2. Seated Calf Raise
The seated calf raise exercise works your flexor digitorum longus using plantar flexion.
- Sit in a chair with your knees bent and your feet flat on the floor.
- Place your hands on your knees and press downward.
- As you are pressing down, lift your heels as high as you can while keeping the balls of your feet on the floor.
- At the top of the movement, squeeze your calf muscles and hold the contraction for two to five seconds.
- Relax your legs and lower your heels back to the floor.
Place a weight across your knees to make this exercise more challenging or perform standing calf raises, as recommended by ExRx.net.
3. Towel Bunching
You use your flexor digitorum longus on a daily basis to help your toes grip the floor or the inside of your shoes. The towel-bunching exercise utilizes this action to work the muscle.
- Place a medium size towel flat on the floor in front of a chair.
- Sit in the chair and place your foot flat on the towel.
- Use your toes to grip the towel and pull it toward your heel.
- Continue through the length of the towel then spread the towel back out and repeat the exercise with your other foot.
Read more: How to Stop Foot Pain With 7 Easy Exercises
4. Marble Pick Up
The marble pick up exercise, as recommended by the American Academy of Orthopaedic Surgeons, utilizes toe flexion for flexor digitorum longus strengthening.
- Sit in a chair with your feet on the floor.
- Place 20 marbles next to one foot.
- Place a small cloth on the floor on the opposite side of your foot.
- Pick up one marble at a time with your toes and place them on the cloth.
- Repeat three times.
5. Barefoot Walking and Running
Walking or running barefoot on uneven surfaces, such as sand or grass, is a great way to target your flexor digitorum longus.
As explained in an article published in April 2012 by the Strength and Conditioning Journal, going barefoot also increases proprioception — or feedback to your brain about the position of your foot. This in turn improves your balance.
- Check for broken glass, rocks and stickers before taking your shoes off and beginning this exercise.
- Walk or run barefoot for five to 10 minutes a few times a week.