Building core strength is important in prevention of back pain and injury. Your core also plays a vital role in supporting and connecting your trunk to your legs, providing stability and effecient transference of energy not just in sports but in everyday movements too.
The important thing to remember is that you should spend just as much time planking and strengthening your lower back as doing “vanity” exercises like crunches. Performing plank exercises for 5 minutes per day, with good form, coupled with abdominal crunches will help improve your core strength and help prevent injuries to your back.
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