Fluid weight question?

If you had a beam that was submerged underwater at a depth of 50' the quivalent load would be 62.4 pcf*50 ft*1 ft= 3120 lb/ft. if the beam was 8 ft then the resultant force would be 24960 lb. When I think about it that number is really high. If I were to swim down to a depth of 50 ft and used my body to act as a simply supported beam I can't imagine 24 kips of force on my back. Can someone please help me understand this. thanks