Please choose the correct ending to complete the given sentence: Health: [header] How to lose arm fat fast [title] Do bicep curls. [step] Stand up straight and hold a dumbbell in your hand so your palm is facing outward. Then, exhale while slowly lifting the dumbbell up to your shoulder.

Ending1: As the dumbbell reaches your shoulder, give it a slow and controlled swing. Do not raise the dumbbell past shoulder height, but drop your arms as much as possible. Ending2: [substeps] Slowly raise the dumbbell off the ground so that it's almost touching your shoulder. Use this exercise on both arms at once. Ending3: Keep your weight in your palms and move the dumbbell forward so that it's resting on your bicep. Your body should be partially upright with your arms arched out to your sides and your arm at a 90 degree angle. Ending4: Flex your bicep as your lifting the dumbbell. Once your bicep is fully flexed, inhale and slowly lower the dumbbell back down to your side.

Answer format: ending1/ending2/ending3/ending4