When it is cold, you can either choose to put on a coat, or be cold and suffer the consequences. You can decide to stay in on extremely windy days or to avoid exposure to bright sun, or you can live with the consequences of exposure to these forces.
The climate has the potential to enhance the Qi or, in excess deplete or damage the Qi. You know that watching the sun set over the mountains in nature stimulates and inspires the Qi. The same sun at midday in summer, if you are unprotected, can deplete energy in the short term and cause exhaustion and dizziness. Besides the natural climates there is a wide assortment of external influences including exposure to stressors and toxins in food, water, air, and the environment, that have the potential to damage and deplete the Qi as well.
The key point regarding Conserve Qi and these external factors is choice. You have to take that coat, wear that hat, use that umbrella, take care to shield yourself from excessive sun, build a fire make hot tea, take a vacation.
If it is too grueling to drive to your work through heavy traffic, you are the only person who can find yourself a new job. If it is obvious to you that certain foods cause you sudden fatigue, it will be you who must make the choice to avoid that food.
If you find yourself saying that you don’t honestly think you can change your behavior or the behavior of others in regard to weather, work, food, and other external stressors, the definitely accelerate your Qigong practice.
This can neutralize the negative effects of many stressors. However, if you accelerate Qigong and become more skilled at conserving Qi through your choices, this will create a radical multiplication of your personal potential and Qi wealth.
[Excerpt from The Healing Promise of Qi page 149-150]