Feeling heavy without weight gain can stem from several factors, including mild dehydration which impairs circulation and cellular function. Hormonal imbalances, such as those related to menstruation or thyroid issues, and mental health conditions like depression and anxiety can also contribute by affecting energy regulation. Chronic stress, leading to elevated cortisol levels, further exacerbates fatigue and a sense of physical heaviness. Addressing these underlying issues through hydration, professional support, or stress management can help alleviate the symptoms.