A dream in which you were keeping fit by working out—whether it was in the gym with weights or on an exercise machine, or following an exercise video at home—may be commenting on your real-life need to gain or lose weight.
If you already take good care of yourself and exercise regularly your dreaming mind could have been encouraging you to build up a different kind of strength and stamina; not necessarily physical, but emotional or intellectual.
Alternatively, keep-fit dreams could have been commenting on how you are feeling in real life. For example, if you were running on a treadmill, do you feel that you are expending a lot of energy but actually getting nowhere? If you were lifting weights, do you feel you are shouldering a burden in waking life? If a fitness instructor is yelling at your exhausted dream self, do you feel that you are being pushed beyond your limits by someone who has authority over you in real life? Dreams in which you are practicing or watching yoga may be urging you to take a more flexible approach to life. They may also be encouraging you to step back from outward activity for a while to explore your inner motivations.
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