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Flexor digitorum superficialis exercises to stretch and strengthen your muscles

These 3 dynamic drills are simple but effective strength builders.
Written By  Liam Brown
Last Updated on 2nd March 2021
Illustration showing the anatomy of the flexor digitorum superficialis muscle

Out of the many forearm muscles, the flexor digitorum superficialis is the biggest of all those that reside in the anterior compartment. And, because it does more than just flex the wrist (more on its functions in a sec), it’s extremely important to keep this muscle strong and healthy if you want to avoid inures.

But before we get into the specific flexor digitorum superficialis exercises, let’s take a quick anatomy recap to understand how this important muscle functions.

Related flexor exercises/stretches:

Flexor digitorum superficialis anatomy

The flexor digitorum superficialis, as the name suggests, is one of the main superficial forearm flexors, which means that it sits very close to the skin. It’s also little surprise that a muscle this large (large for the forearm, that is) has two distinct heads. [1]

The humeroulnar head, unsurprisingly, originates from the humerus, whereas the radial head originates at the radius.

Besides being a powerful wrist flexor, the flexor digitorum superficialis is unique in the fact that it can flex your fingers individually (digits 2-5).

As you’ll soon learn, you need to be aware of both of these functions if you want to train your flexor digitorum superficialis optimally and achieve the best results.

Flexor digitorum superficialis exercises

To strengthen the flexor digitorum superficialis and develop your forearms to their fullest potential, you need to select one exercise that emphasizes wrist flexion and one drill that trains finger flexion. [2] And—lucky you—that’s exactly what I’ve done here.

1. Wrist curl

Man doing seated forearm curls

The wrist curl is a common bodybuilding exercise. Yet anyone seeking stronger forearms can benefit from this exercise. Here’s how to do it:

  1. Grab a pair of light dumbbells and place the top of your forearms on a bench (or table) so that your palms are facing up.
  2. Allow your hands to hang off the edge of the surface.
  3. Lower the dumbbells towards the ground until you feel a deep but comfortable stretch.
  4. Curl the weights back up by flexing your wrists.
  5. Squeeze your forearms and repeat for a total of 2-3 sets before switching arms (if you're working one arm at a time). Stick to high reps (12-20) to avoid straining your wrists.

2. Hand grip squeezes

Man using a hand strengthener

This is one of the most convenient flexor digitorum superficialis exercises because you need only one piece of equipment. Therefore, there’s no need to go to a gym. If you wanted, you could even do this exercise while lying in bed. But, for the benefit of your posture, I recommend doing this drill while sitting in a chair.

  1. Place one side of a hand gripper in the palm of your hand, and then wrap your fingers around the other end.
  2. Squeeze the two gripper ends towards each other by bringing your fingers towards your palm.
  3. Keep squeezing until the two ends touch.
  4. Release the gripper, but be sure to resist the tension on your way back to the starting position.
  5. Repeat for 3-4 sets of 10-12 reps. You might also want to use chalk if you’re doing this exercise for muscle growth, because in that case, you’ll be lifting heavier.

3. Weighted carry

Man doing farmer's carries

This exercise is great for the flexor digitorum superficialis because it relies on strong finger flexion to keep the weights from falling out of your hands. I like to do this exercise while walking, but you can get the same grip strengthening benefits from just doing it statically.

  1. Grab two heavy dumbbells (remember, heavy is relative) that you can hold for around 30 seconds (it may take trial and error to find your ideal weight).
  2. Hold the dumbbells by your sides and maintain a good, upright posture.
  3. Make sure that the dumbbells start off in the palm of your hands.
  4. Maintain a firm grip on the dumbbells as you walk back and forth with them.
  5. Repeat the movement for 2-4 sets and increase the time under tension to 45-60 seconds once the initial 30 seconds become easy.

Don’t forget the extensors!

Do you need to train the flexor digitorum superficialis separately?

Senior holding a dumbbell in his hand

When deciding how to best train a muscle, it’s important to think about the functions that that muscle is responsible for. [3]

Why?

Because many forearm muscles perform the exact same functions. And while you might be able to modify the resistance curve in some flexor digitorum superficialis stretching exercises, most isolation exercises are still going to work multiple lower arm muscles.

The flexor digitorum superficialis already gets plenty of stimulation during regular resistance training.

So, to answer the question, no, you don’t need any special flexor digitorum superficialis exercises in your routine as long as you're doing some kind of grip training.

As for the flexion component of the flexor digitorum superficialis, you could do wrist curls. However, if you already do back and bicep training (or even manual labor), then it’s highly likely that your flexors are getting plenty of stimulation already.

Related posts

Conclusion: Which flexor digitorum superficialis exercises are the most effective?

Usually, the best exercise for a particular muscle depends on the context. But on this occasion, I think that the conclusion is pretty cut and dry.

Since the weighted carries/holds train both wrist flexion and finger flexion, they’re superior to regular wrist curls. Plus, you can do them with virtually any heavy household object (better fill up those shopping bags) that you can grip.

The hand gripper is a good alternative. But since most people do this exercise slumped in a chair rather than while walking (as with the static holds), it doesn’t have as much functional carryover to everyday activities.

References

  1. Sendic, G. (2020, October 29). Flexor digitorum superficialis muscle. Kenhub. https://www.kenhub.com/en/library/anatomy/flexor-digitorum-superficialis-muscle
  2. Flexor Digitorum Superficialis. (n.d.). Department of Radiology University of Washington. https://rad.washington.edu/muscle-atlas/flexor-digitorum-superficialis/
  3. Okafor, L. (n.d.). Anatomy, Shoulder and Upper Limb, Hand Flexor Digitorum Superficialis Muscle - StatPearls - NCBI Bookshelf. National Center for Biotechnology Information. https://www.ncbi.nlm.nih.gov/books/NBK539723/
Liam Brown
Liam Brown has been coaching clients as a personal trainer for more than 12 years. Raised by his athlete mother and physiotherapist father, he understands the critical importance of learning the proper technique for both avoiding injury and building muscle.
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