Rest your hip. Sore hip flexor muscles can benefit from rest. Avoid the activities that caused your pain. Ice your affected hip for 20 minutes at a time, several times a day. Keep the leg of your affected hip elevated as much as possible 48 hours from the first onset of pain. You can also take over-the-counter pain medications to help control pain.
Protein, you may have heard, is what your muscles are made of. Well, not quite. The amino acids that make up protein are the building blocks of muscle, and your body needs—not wants, needs—these substances during and after training for repair and recovery. It breaks down the protein into the respective aminos, uses them for their various functions, and then you convert what doesn't get used. I break down a lot of tissue in my daily workouts, so balancing it out with adequate amounts of protein throughout the day is important.
Remember my special answer: here it is… MOUTHTAPERS exist. People out there will tape their mouth closed during sleep so that they can breathe their nose. Even during the day sometimes. Why? Because the nose is directly connected to the diaphragm while the mouth is connected to the chest. Sure, increase chest mobility and your lungs may be able to expand more which will allow more air to be held, BUT HOW CAN YOU HOLD THAT MORE AIR IF YOUR DIAPHRAGM is weak? You won’t. So everything I just talked about must be done through the nose. Notice yourself breathing with your mouth and SWITCH right away. It takes work and energy. How you breathe during the day rolls over to how you breathe during the night.