2 Simple Exercises to Strengthen your Foot and Arch Muscles
Strength within the foot and arch is essential to supporting the health of your feet and keeping you safer from injury. The intrinsic muscles of the foot are what keep you from sinking into your pointe shoes or using a stiff shoe like a crutch, and strengthening the intrinsics will help you articulate through your feet and support yourself en pointe. Intrinsic means that the muscles start and end within the foot itself-- they don't cross the ankle or toe joints and don't produce any action on those joints. The lumbricals in particular are the intrinsic muscles of the foot whose main function is to support the arches, metatarsals, and bones of the midfoot.
Since these are small muscles, they aren't the first things your brain recruits when you want to point your feet or rise up onto your toes. The first muscles your brain calls are usually the largest, strongest muscles that you use all the time--your ankle and toe flexors (the Gastrocnemius and Flexor Hallicus Longus or Flexor Digitorum Longus, for example). So, in order to target the intrinsics in a strengthening exercise instead of those big guns, you really need to train your brain how to recruit them. This takes small, specific exercises, and lots of practice.
First, sit with your leg out in front of you and have a pillow or squishy ball propped up against a wall in front of your foot. Slowly point into the pillow/ball, going through the demi pointe, but making sure to avoid curling the toes. Keeping the toes long reduces the chances of using your long toe flexors. Those muscles start in the calf, cross behind your ankle, and go all the way down into the toes. If overused, they can become inflamed, and you also want to make sure you never curl your toes while en pointe. So, teaching yourself to point without curling really targets the strength of those intrinsic muscles while avoiding overuse of the long toe flexors.
The second exercise I recommend for specifically strengthening the foot intrinsics is a tricky one and can take some practice. Sit with your foot flat on the floor and try to lift up your arch while keeping the toes long and flat. Again, we're avoiding that curling of the toes and only targeting the small muscles under the arch. This is a small movement, really just lifting the arch up into a more pronounced dome shape. Just slowly lift the arch and relax, paying close attention to keeping the toes and calf soft and relaxed.
Doing these two specific exercises regularly can really work wonders to strengthen those intrinsic muscles of your foot, keep you pulled up in your pointe shoes, and articulate your feet!