The cool breeze of fall has been replaced by the icy chills of winter. As a ballet dancer, I layer sweaters and leggings, trash bag pants- anything to keep warm. During rehearsals, I even wore socks underneath my pointe shoes to thaw my numb toes. However, there is no substitute for doing a thorough warmup to prime the muscles for exercise and prevent injury. Plus, these warm ups can also be a precursor to flexibility training as well. Here are some of the exercises that I find helpful to warm up.
1. Theraband Exercises
Exercise #1: I tie a theraband around my thighs, near my knees. Slowly, I plie in first position, and straighten my legs. I
repeat this around fifteen to twenty times. This exercise can also be done in the other basic ballet positions or even turned in with the knees facing front and legs spread hip distance apart.
Benefit: I find that the resistance from the theraband helps me activate my external rotators and other turnout muscles without doing extreme activity. When doing this basic movement, I can pinpoint certain muscles around my hips and simultaneously work through any misalignment in my form.
Exercise #2: With the theraband still tied around my legs, I start in first position. I brush my right leg to the front, going through the ball of my foot to point my toes. Then, I reverse this process to close back into first position, repeating ten times to the front, side, and back. I do these exercises for my left leg as well, and sometimes from fifth position.
Benefit: Doing tendus with the theraband works my lower back as well as my legs, as I have to keep my hips in one line. This exercise also helps me to warm up my feet and ankles, rolling through my foot, and practicing the proper technique for standing on the balls of my feet (releve) and pointe work.
Exercise #3: Sitting on the ground, I have my legs straight infront of me, the theraband untied and without knots. Putting 
one foot in the middle of the band and holding either end of the band in my hands, I point and flex my feet, feeling the resistance in my ankle. One set for this exercise is twenty repetitions. I then repeat for the other foot.
Benefit: This exercise promotes ankle stability and strengthening of the foot, which prevents injury and gets me ready for pointe work. This way, the ligaments and tendons in my foot are not overstressed when immediately jumping into complex ballet movements.
2. Stretchband (Flexistretch) Exercises
Exercise #1: I take my flexistretch, or other stretching band- preferably one with two loops at either end- and insert my feet through each of the loops. Laying on my back, I raise my legs so that my toes are pointing toward the ceiling, my
legs being a ninety degree angle to my torso. I then open my right leg to the side, so that I am in somewhat of a straddle position, bringing my leg as close to the floor as possible. I then bring my right leg back to meet my left leg, and repeat for the left leg. I do each repetition (right leg and left leg) about twenty times.
Benefit: This exercise I find especially helpful to prepare for middle splits. I also get to use my glutes and even inner thigh muscles to rotate and bring my legs back together. When I stretch for middle splits after doing this exercise, I do not feel tension in my inner thigh and around my hip joint.
Exercise #2: With a stretching band or the flexistretch, I insert my feet through the loops and stand next to a barre or tabletop, hanging on with one hand for balance. Beginning from 5th position, I raise my leg through retire, and extend 
my leg to the front. It is crucial that I maintain proper form by pulling up through my supporting side (the leg not doing the work). I have to keep my working foot pointed and use my hamstring and inner thigh muscles to turn out my leg. The band pulls my leg downwards, but I resist it to extend my leg up and out, gently lowering my leg back down to fifth position. I repeat ten times to the front, side, and back and the same for the other leg.
Benefit: One important movement in ballet is called develope, extending the leg to the front, side, or back, with intentional placement. This exercise helps me to gain strength in my hip flexors and allows me to work on my alignment so that I can perform the same action later in class or rehearsal.
3. Ankle Weight Exercises- the weights I use are 2.5 lbs each
Exercise #1: With the ankle weights on my feet, I sit with my legs straight in front of me, turned out in first position. I raise one leg up, turned out, bring it slowly to the side turned out. I then lift the leg back to the front, and lower it back down to first position. I alternate each side, completing fifteen to twenty repetitions of right and left. A variation of this exercise
can be done with the non-working leg bent in a turned out position. During the exercise, I try to keep my back straight and flat; sometimes it helps to have a flat wall behind my back.
Benefit: This exercise helps me engage the muscles on the inside of legs, running all the way down to my lower calf. I can isolate those muscles when turning out to the side, and lifting from the side to the front. Training these muscles is essential for movements that require some develope to the front where it is very clear whether the leg is turned out or not.
Exercise #2: With ankle weights, I lay on my back with both legs straight and turned in (there is a variation to the front and side where the non-working leg is bent). I raise one leg to about forty five degrees, and lower it back down, lightly 
touching the ground. It helps to feel the exercise by not fully stretching my leg, feeling my hip flexor instead of my quadricep. I repeat twenty repetitions to the front, side, and back, and to the other side.
Benefit: When I was in physical therapy, my hip flexor strength was evaluated, and was actually quite weak. This exercise has allowed me to feel my hip flexors engage so that when I develope my leg, I can extend instead of gripping my muscles. Strengthening my hip flexors has allowed me to lengthen in my legs and pull up in my hips so that I have less strain on my hip joints.
These are only some of the many exercises I have found effective, but it does take some personal trial and error to find what works best. I hope some of these exercises prove helpful in the future.