So if you're doing abs exercises and you feel like your hip flexors are putting in more work, refocus and dial in on the muscles you're trying to target. It might sound trite to just "think" about a muscle working as you're doing an exercise (for example, thinking about your abs contracting as you do a situp), but it might actually prevent you from mindlessly grinding out reps with poor form.
Progress to add core engagement.  Once they can master the posterior pelvic tilt, I usually progress to assist by curing core engagement.  You can do this by pacing both hands together on top of your front knee and push straight down, or by holding a massage stick or dowel in front of you and pushing down into the ground.  Key here is to have arms straight and to push down with you core, not your triceps.
You can use over-the-counter remedies such as Motrin or Advil (ibuprofen) or Aleve (naproxen) to help with pain and swelling. Tylenol (acetaminophen) works for pain relief, but it doesn't treat inflammation and swelling. If you have heart disease, high blood pressure, kidney disease, or if you've had ulcers or internal bleeding, check with your doctor before taking any of these medications.
Our hip flexors serve many vital functions. The goal of the hip flexor is to make it easy to for joints to move through their full range of motion smoothly.  They’re responsible for important aspects of motion, like our ability to bend, run, or kick. Without our hip flexors, controlling the movement of our legs would be virtually impossible. Our hip flexors also work to stabilize the joints of the hips and lower body.
You're more likely to get a hip flexor injury if you've had one in the past, you don't warm up properly before engaging in athletic activity, your muscles are already tight or stiff, or your muscles are weak from being overused. If, while exercising, you try to do too much at once in too short an amount of time, you can also put yourself at risk for a hip flexor injury.
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