Which of the following is NOT a recommended practice to prevent DCS?

To effectively prevent decompression sickness (DCS), it's crucial to adhere to best practices that manage the body's exposure to nitrogen while diving and in the immediate post-dive context.

Overhydrating before a dive, while it might seem like a good idea to increase blood circulation and help in the elimination of excess nitrogen, is actually not a recommended practice. The body needs to maintain a proper balance of fluids. Overhydration can potentially lead to a condition known as "water intoxication" or dilutional hyponatremia, which can disrupt the electrolyte balance and lead to further complications while diving rather than mitigating the risk of DCS.

In contrast, monitoring nitrogen levels is important to understand how much nitrogen the body is absorbing during the dive. Ascending slowly allows for the safe elimination of nitrogen from the body, minimizing the risk of bubble formation. Finally, avoiding flying immediately after diving is crucial because changes in altitude can exacerbate the risk of DCS due to reduced atmospheric pressure while the body is still off-gassing nitrogen. These practices are all key components in managing the risks associated with diving.