bad condition, poor shape, unfitness - poor physical condition; being out of shape or out of condition

asthenia, astheny - an abnormal loss of strength

cachexia, cachexy, wasting - any general reduction in vitality and strength of body and mind resulting from a debilitating chronic disease

weakness - the property of lacking physical or mental strength; liability to failure under pressure or stress or strain; "his weakness increased as he became older"; "the weakness of the span was overlooked until it collapsed"