Try one of these Warm-Up or Stretching exercises before your next workout to kick start the metabolism, increase flexibility and mobility, and lubricate the joints in order to avoid injury and maximize results. Look and feel your best right from your own home with trainers such as Jillian Michaels, Billy Blanks Jr, Kathy Smith, Denise Austin, Samantha Clayton, ENVY Girls, and Garret Amerine. less