Final answer:
When performing curl-ups, your arms should stay flat on the mat, the given statement is b. false because the correct position for your arms during curl-ups is to cross them over your chest or place your hands behind your head, with your elbows pointing out to the sides.
Step-by-step explanation:
When performing curl-ups, your arms should not stay flat on the mat. The correct position for your arms during curl-ups is to cross them over your chest or place your hands behind your head, with your elbows pointing out to the sides. This position helps to engage your core muscles and prevent your arms from assisting in the movement.
Having your arms flat on the mat would provide additional leverage and make the curl-up exercise easier to perform. This would reduce the challenge to your abdominal muscles and potentially lead to a less effective workout.
By keeping your arms in the correct position, you are placing more emphasis on your abs, ensuring that they are doing the majority of the work during the curl-up exercise. This helps to strengthen your core muscles, improve stability, and prevent potential injuries from compensating with other muscles. So therefore the given statement is b. false