What you’re describing sounds less like a lack of willpower and more like anticipatory anxiety with an avoidance cycle. You decide the night before that you’ll exercise, but when the actual moment comes, your body goes into an anxiety response—palpitations, restlessness, foggy feeling and low motivation. Because you avoid going downstairs, the anxiety temporarily decreases, which unfortunately reinforces the avoidance and makes the next attempt harder.
The important thing is not to force yourself into intense exercise immediately. Start extremely small—for example, just put on your shoes and go downstairs for 5 minutes of slow walking. Once you are comfortable, gradually increase the duration. The goal initially is to break the avoidance cycle, not to burn a lot of calories.
At the same time, because you’re experiencing palpitations, significant fatigue and low motivation, it would be useful to assess for anxiety/depression and physical contributors such as
thyroid problems, anemia,
vitamin deficiencies, sleep issues, etc. If these symptoms are occurring in other areas of life too, please discuss them with a psychiatrist/physician rather than assuming it is simply a motivation problem.
You are not lazy or weak—your brain is learning to avoid something that it currently associates with anxiety, and this pattern can be changed.
Next Steps
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