Please choose the correct ending to complete the given sentence: Health: [header] How to gain flexibility in your hips [title] Warm up with light cardio for 10-15 minutes. [step] Jumping jacks, walking lunges, heel kickbacks, and marching are great activities to warm you up. Warming up will help prevent injury as you stretch.

Ending1: [substeps] Start by standing up straight with your feet slightly slightly closer together. Do this for 10-15 seconds while holding your legs on either side of your body. Ending2: [substeps] Stand on a sturdy chair or platform. Squeeze your knees together and lean into the seat. Ending3: [title] Kneel on the floor with your right leg bent in front of you. [step] You should have your left knee on the floor and your right knee pointing in front of you, with both of your legs bent at right angles. Ending4: [substeps] To warm up with a good core workout (repeating the exercise but kicking your legs forward), you don't do weight-bearing exercise. Focus on hiit workouts that focus on muscle groups, like pelvic muscles, and target your abs.

Answer format: ending1/ending2/ending3/ending4