To achieve Jennifer Aniston's arms, try:
Push-ups: Although there are many variations on the push-up, the basic principle remains the same: Engage your upper back, shoulders, and arms to lift your body weight off the floor, then slowly lower it back down.
Shadow boxing: Basically you throw punches whilst no one is standing there. Be sure to engage the core whilst doing these exercises. Try cross punches and upper cuts to work different muscles.
