Liquid Assets

Subscribe | Advertise | About Us | Contact Us | Home

April 2005

By R. Barry Dale, PT, PhD, SCS, ATC, CSCS; Jacqueline MacDonald, PT; and Lita Messer, PTA

Aquatic therapy offers benefits to a wide range of clinical populations

Water-based therapy dates back to ancient history. Greek and Roman culture embraced water and its medicinal properties. Hippocrates prescribed bathing and water-based exercise for many ailments, and the Romans developed elaborate bath houses complete with dressing rooms and various pools of different temperatures. The properties of water are ideal for physical rehabilitation, and today, aquatic therapy continues to grow as a market segment.

Aquatic therapy is indicated as a viable, and in many cases preferred, treatment option for virtually any diagnosis. Patients who are most commonly referred and who appear to gain the most from aquatic rehabilitation are those that have difficulty performing or tolerating traditional land-based therapies. Therefore, aquatic therapy could be used to implement modified functional activities as a transition to function-based rehabilitation on land.

For example, a key issue for orthopedic patients is their inability to tolerate or perform weight-bearing activities. The buoyancy of water relieves some of the patient’s body weight and as a result is beneficial to orthopedic patients whose goals are to gain range of motion, improve core trunk stability, minimize pain, and reduce weight-bearing forces through the joints. Adjusting water depth controls the amount of body weight that must be supported by weight-bearing joints as weight decreases with immersion depth. For example, immersion to the level of the anterior superior iliac spine, xiphoid process, and seventh cervical vertebra decreases weight-bearing by approximately 50%, 70%, and 92%, respectively.¹

Aquatic therapy benefits many orthopedic conditions, including muscle and connective tissue injuries such as strains, sprains, contusions, and tendonitis; articular injuries associated with trauma or overuse syndromes; post-fracture (nonacute and stable); and various pathologies of the vertebrae and intervertebral discs. In addition, many patients are candidates for aquatic therapy before and/or after orthopedic surgery.

Neurological patients need to regain proper neuromuscular tone and control for proper performance of functional activities. Aquatic therapy may help the patient accomplish these in a safe and controlled environment. The following neurological conditions may benefit from aquatic rehabilitation: stroke, spina bifida, Guillain-Barre syndrome, peripheral neuropathy, spinal cord injuries, traumatic brain injuries, and Parkinson’s disease.²

Aquatic therapy may help the clinician manage the patient’s muscle tone. For example, rigid and/or spastic muscles will tend to sink, and floppy or flaccid muscles will float, which will be noted immediately as the patient enters the water. The clinician can then provide appropriate support to the patient.

An additional benefit to the neurological patient is that water increases sensory input to the body. The water constantly challenges balance, requiring the patient to stabilize proximally in order to remain upright. Creating turbulence in the water or performing deep-water activities where the body is free floating with no external support can challenge balance further.

Deconditioned patients have poor endurance, generalized weakness, and impaired functional abilities and exercise plays a major role in the success of these patients. The aquatic program is an ideal place to introduce exercise and functional training. The buoyancy properties of water will assist these types of patients perform activities that are difficult to perform on land. Gastric bypass patients present with a unique type of debility associated with deconditioning and usually have comorbidities such as joint pain and/or joint degeneration. However, patients who have undergone gastric bypass or who are otherwise deconditioned seem to progress well with aquatic therapy.

PRINCIPLES OF AQUATIC CONDITIONING
Aquatic conditioning requires attention to several factors that affect physiological responses during water-based exercise. Cardiovascular conditioning in water is relatively more intense than land-based exercise. This is partially due to the viscosity of water, which provides considerably more resistance than air. Therefore, heart rate (HR), rate of perceived exertion, and energy expenditure respond differently to exercise in the water versus land-based activities. Thus, appropriate adjustments are necessary to implement an effective aquatic conditioning program. With shallow-water walking or running, target HR should be adjusted downward by seven to nine beats per minute (bpm).³ For example, a patient would theoretically reach a land-based target HR of 150 once their aquatic exercise pulse reaches 141 or 143 bpm. Deep-water running, on the other hand, requires a downward adjustment of about 17 bpm.⁴

Other means to monitor intensity during deep-water running include cadence and the Brennen perceived exertion scale.² Cadence is calculated by 1) Counting the repetitions that a specified (right or left) knee produces during a given period of time (15, 20, 30, or 60 seconds); and 2) Multiplying the number of repetitions by a factor that produces a rate during 60 seconds. For example, consider that a patient’s right knee produces 20 repetitions during 20 seconds of time. The factor needed to equate 20 seconds to 1 minute is 3, and thus the patient’s cadence is 60 cycles per minute. Coincidently, deconditioned patients should begin deep-water running with a cadence of less than 60 cycles per minute.² The Brennen perceived exertion scale is a five-point scale that ranges from very light to very hard.² The scale also equates the intensity of deep-water running to exercise intensities on land: level one is equivalent to a slow walk whereas level five is equivalent to sprinting.²

Water temperature is also important to consider during aquatic aerobic conditioning. Ideally, water temperature should be between 26° and 28° C (79° to 82° F) to dissipate metabolic heat generated during an exercise bout.4 This temperature range is somewhat less than the temperature of most therapeutic pools, which is usually 30° to 33° C (86° to 92° F). Thus, sustained conditioning activities may need to occur in a fitness pool, rather than a “therapy” pool.

Resistance and assistance are affected by modifying lever-arm length, the surface area of the moving body part, and the movement velocity. These principles hold true with or without the addition of special equipment available to the aquatic therapist. Longer lever arms generally increase resistance or assistance. Increasing surface area causes the moving body part or object to collide with more water molecules affecting the flow of water around the object, which in turn increases the resistance encountered. Increasing exercise velocity is another means to increase resistance.

EQUIPMENT CONSIDERATIONS
Aquatic equipment allows for the progression of treatment, making activities more challenging by increasing lever arm length and/or surface area. Equipment used in aquatic therapy also increases buoyancy, which in turn acts as a resistance or assistance force. For instance, flotation devices improve buoyancy, but an increase in surface area could increase resistance. Buoyancy behaves as a resistance force when elbow extensors act to hold a buoyant dumbbell underwater and provides assistance when a buoyancy cuff around the ankle pulls the lower extremity into flexion. Kickboards, paddles, dumbbells, and cuff weights of various sizes also can be used to increase surface area and therefore resistance during walking or balance activities. Paddles and special dumbbells offer resistance for upper extremity exercises.

Dumbells used to increase surface area and resistance.

Dumbells can be used to increase surface area and resistance during walking or balance activities.

Noodles, inner tubes, and flotation belts increase buoyancy and generally serve as flotation devices. Noodles are versatile tools, and some examples of their use include: 1) challenging support during standing activities; 2) straddling them to assist with trunk stabilization; or 3) serving as resistance underneath the patient’s foot during a simulated standing leg press. Having the patient “hang” upright in a tube can also offer mild distraction for back pain patients. Flotation belts work well to support patients in deep-water activities.

Patients may also perform activities in supine, prone, or upright position. Activities in supine or prone will promote trunk flexion or extension, respectively.

Aquatic rehabilitation is a skilled intervention that offers unique benefits to many different types of medical conditions. It may improve mobility, strength, balance, and aerobic condition for many medical diagnoses. The clinician has many equipment options to consider during the progression of an aquatic therapy program.

R. Barry Dale, PT, PhD, SCS, ATC, CSCS, is an assistant professor of physical therapy at the University of South Alabama, Mobile; Jacqueline MacDonald, PT, and Lita Messer, PTA, practice physical therapy at Mobile Infirmary Medical Center, Mobile, Ala.

REFERENCES

Thein-Nissenbaum J. Aquatic rehabilitation. In: Wilk K, ed. Physical Rehabilitation of the Injured Athlete. 3rd ed. Philadelphia: Saunders; 2003:295-314.
Triche T. Special topics: aquatic therapy for the injured athlete. In: Wilk K, ed. Clinical Orthopedic Rehabilitation. 2nd ed. Philadelphia: Mosby; 2003:503-511.
Hall J, Grant J, Blake D, Taylor G, Garbutt G. Cardiorespiratory responses to aquatic treadmill walking in patients with rheumatoid arthritis. Physiother Res Int. 2004;9(2):59-73.
Hamer P, Slocombe B. The psychophysical and heart rate relationship between treadmill and deep-water running. Aust J Physiother. 1997;43(4):265-271.

LOOKING FOR EXPERT ADVICE?

Experts here are available to answer all your questions!

Please contact us for more information about this feature, or to become an expert.

MEDIA CENTER

Interactive Media

Resources

	Calendar
	Consumer Resources
	Media Kit
	Advertiser Index EAB Reprints Submit an Article

ADDITIONAL ONLINE RESOURCES

Allied Media
24X7mag Clinical Lab Products (CLP) Orthodontic Products The Hearing Review Hearing Review Products Rehab Management		Physical Therapy Products Plastic Surgery Practice Imaging Economics RT Magazine Sleep Review