A hypotonic solution is any solution that has a lower osmotic pressure than another solution. It is a solution that has less solute and more water than another solution.
In a hypotonic solution, there is more free water outside the cell than inside the cell. As a result, water will diffuse into the cell through the process of osmosis
If an individual is sweating a lot, he/she are losing two things: water and salt . This means that their blood is losing both as well. The loss of salt is important because you need a certain salt and water concentration for proper cellular function. At the moment one sweating, with the cells losing water, they are moving towards a hypertonic phase. One would want a hypotonic solution to replace lost salts.
This can be made possible through reproductive cells undergoing meiosis since such process has specialized sex cells split and multiple after copulation. To answer the question if is it possible for a human to survive without a reproductive system, the answer is yes.