Chapter 9: Aquatic Exercise

Introduction

Water therapy, the use of water for rehabilitation purposes, has been considered beneficial to people’s health throughout history and dates back thousands of years.¹²⁶ Ancient cultures utilized hot springs to improve circulation and relaxation.¹²⁶ The use of water for restorative purposes has grown in popularity and has gained increased use in facilitating therapeutic exercise. The unique properties of the aquatic environment provide clinicians with treatment options that may otherwise be difficult or impossible to implement on land. Using buoyant devices and varied depths of immersion, the practitioner has flexibility in positioning the patient (supine, seated, kneeling, prone, side-lying, or vertically) with any desired amount of weight-bearing. A substantial and growing body of evidence describes aquatic intervention for rehabilitation purposes and indicates its beneficial effects for rehabilitation of a variety of clinical conditions. Overall, the available evidence indicates that aquatic intervention is safe and appears to have minimal to no adverse effects. Aquatic exercise has been successfully used for a wide variety of rehabilitation populations including pediatric,^{12,42,51,69,100,119,128,135} orthopedic,^{3,6,13,15,16,20,25,27,37,39,43,46,53,72,74,102,130} neurological,^{53,78,84,92,96} and cardiopulmonary patients.^32,68,127

Background and Principles for Aquatic Exercise

Definition of Aquatic Exercise

Aquatic exercise (water-based exercises) refers to exercises that are performed in water in multidepth immersion pools or tanks. Aquatic therapy is the use of water for rehabilitation purposes. If the clinical decision is to use aquatic exercise as the treatment modality, certain aspects of the intervention should be considered.¹²⁴ Aquatic exercise can be used to facilitate the application of established therapeutic interventions, such as stretching, strengthening, joint mobilization, balance and gait training, and endurance training.

Properties of Water and Immersion

Water is a unique environment. Previous reports have identified the aquatic environment as a beneficial tool in exercise and rehabilitation. The beneficial effects are primarily due to the unique properties of water and immersion that have profound physiological implications in the delivery of therapeutic exercise. To utilize aquatics efficiently, practitioners must have a basic understanding of the physical properties of water and clinical significance of the static and dynamic properties of water as they affect human immersion and exercise. Understanding the clinical properties of water is important to appropriately select exercise and treatment techniques, as well as why to choose the aquatic environment for a particular person.¹⁰⁶

The inherent physical properties provided by buoyancy, hydrostatic pressure, viscosity, surface tension, hydromechanics, thermodynamics, density, and center of buoyancy have a direct effect on the body in the aquatic environment^16,52...