According to Speaker Rich Hopkins, if you are not in the mood to speak and are sick try:
- Medicate - time your medications so they take effect just before you go onstage
- Yield - let your body tell you if you are overstraining and adjust as needed (e.g., sit on a chair instead of standing the entire time)
Tim Wilson
Professional Speech Coach
Free speaking tips at: http://speakingquicktips.blogspot.com