In an August 4 Instagram post, Charles Glass explained how using mirrors can help or hurt your posing routine. Whether the goal is fat loss, muscle-building, or stage presentation, Glass has a toolbox to draw from. While the mirror is essential for learning a posing routine, he believes it eventually leads to diminishing returns if overused. Charles Glass believes the mirror is a double-edged sword, capable of helping or hurting a posing routine. RELATED: Arnold Schwarzenegger Says Shaky Posing On Stage ‘Inexcusable,’ Explains Why Andrew Jacked Won 2026 Arnold Classic