Diving physiology informs you about several things about the underwater environment and how these play an important role in your continued comfort and well-being when you dive. As a new diver—and even as you build experience—you need to understand and take notice of how increased water pressure can impact you, what can happen to your body at depth, why it can happen, how to recognize any adverse symptoms, and what to do in case of an incident.
Diving physiology also includes some information about things that can happen before you go underwater and even after your dive.
Even though diving is said to be 60% mental and 40% physical, there may be times when the diver needs to work hard and exert a lot of physical effort—for example, swimming against a current, climbing up a beach or steep hill, or getting back onto a dive boat after the in-water phase of a dive is over.
A certain amount of physical strength and good cardiovascular health is required. This does not mean that you have to be an Olympic athlete, but at the same time, being overweight and being short of breath after a short walk is not good for diving. So, if you are not doing so already, start to make an effort to keep yourself healthy and do regular exercise to build up the efficiency of your cardiovascular system. This will help make you a better and a safer diver.