Lesson 41

Lesson Two: Swimming and Moving

Course Complete

Learning Objectives

By the end of this section, I should be able to answer these questions:

1. How does water’s density affect moving in water?

2. How do I move efficiently as a diver?

3. How does streamlining benefit me as a diver?

4. Why is trim important to streamlining, moving efficiently and protecting the underwater environment?

5. What skill allows me to use water’s density to make moving in water more efficient?

Swimming and Moving

Because water is so much denser than air, it takes more effort to move in it. The faster you try to swim or move, the more energy you use and the faster you tire because it takes four times as much energy to double your speed.

There’s no reason to rush while diving. To move efficiently as a diver, move slowly and steadily. Avoid rapid and/or jerky moves, which waste your strength. You’ll go much farther and enjoy the dive more if you relax and take your time.

Streamlining reduces drag, which in turn reduces the energy you use underwater. This makes the dive more relaxing and helps you save air. Streamlining is simply the process of wearing your gear close, with nothing dangling, and swimming relatively level in the water. Your instructor will help you during your confined and open water dives.

With correct trim, buoyancy control makes water’s density work for you to move efficiently. As you dive, stay neutrally buoyant – almost weightless – so you glide smoothly through the underwater world, and avoid accidental damage to it with fin kicks or other contact. At the surface, inflate your BCD so you float effortlessly. The ability to change your buoyancy is what makes diving a unique, fun experience.