The present invention is an improved speed bag apparatus having a post 15 connected at its lower end 16 to a speed bag platform 50 by a vibration dampener 40. The vibration dampener rigidizes the connection between the post and the platform. The invention also includes a post collar 20 to guide and capture the post therein. The post is attached to a mounting apparatus which includes support members 31, 32, and 33 and a wall plate 30. The post collar also includes a pivoting clamp arm 60 which may be actuated by a turnable shaft 70 to grip the post as desired.