Physical therapist instructs a patient about core stabilization without compensations. The patient is using hand floats to assist slow, functional movement while maintaining good stabilization.

Patient is in a neutral spine position against the pool wall, receiving instructions about the use of resistive paddles to activate core and scapular stabilizers.

by Anne Plattenburg, PT, MPT

Aquatic physical therapy is a welcome alternative for orthopedic patients struggling with pain-provoking exercises. Degenerative conditions such as arthritis, as well as musculoskeletal injuries and conditions, can make weight-bearing painful through the spine, hips, and knees. The pain and the compensations that often arise can lead a patient to avoid activities and lose strength, stabilization, and balance. The warm-water environment helps to unweight painful joints, improve ease with strengthening, and promote relaxation of tense muscles. The water also provides a supportive and safe medium in which to work on postural control, balance, and correcting gait deviations. When exercise is less painful, the patient’s experience is more positive. Helping to facilitate a positive relationship with exercise can improve a patient’s function and compliance to an exercise program that promotes a healthy lifestyle.

Aquatic therapy is most effective when a therapist successfully integrates the water properties of buoyancy, viscosity, and hydrostatic pressure with the treatment intervention. Because certain health conditions can be adversely affected by these properties, the patient needs to be considered appropriate for the water. A PT evaluation with a thorough medical history review and discussion with the patient should reveal any precautions or contraindications. Any concerns or uncertainties should be discussed with the patient’s physician.

Contraindications and Precautions

A patient with any of the following contraindications is not a good candidate for aquatic PT: uncontrolled hypertension or cardiac instability, incontinence, uncontrolled seizures, open wound(s) or active rash, infectious conditions, suicidal tendencies, or extreme fear of the water. Precautions for warm water therapy can change to contraindications depending on patient response. Precautions include conditions in which thermal regulation is compromised, such as multiple sclerosis or pregnancy. Others include respiratory problems; patients with confusion or disorientation; or patients with significant limitations in strength, endurance, range of motion, or balance, or who are on cardiac medication that can greatly alter cardiovascular response to exercise.

For the patient who discusses apprehension about being in the water, but has a strong interest in trying aquatic PT, precaution is indicated. Often a slow introduction to water immersion with therapist close by can be very effective. Communication between therapist and patient is essential, so the patient feels safe and in control to stop or continue at any time. Any questions or concerns regarding the patient’s health status should be communicated and discussed with the patient’s physician before initiating aquatic PT.

Treatment Expectations for the Patient

The patient appropriate for aquatic PT should have an understanding of this treatment choice, what to expect at treatment sessions, and have all questions answered by the therapist. The therapy pool should have a safe way for the patient to enter and exit the water; stairs with railing is ideal. For patients unable to use the stairs, an ADA-compliant pool lift chair should be available. During an aquatic visit, a therapist may work with the patient from the pool deck, giving instruction for exercise technique and correcting dysfunctional movement patterns. Using the side of the pool or railing can provide support to the patient if indicated during exercises. Various choices of aquatic equipment can provide extra flotation or resistance to progress exercises.

A therapist may also work with the patient inside the pool for manual techniques, tactile cueing for body position, or movement pattern re-training. A therapist in the water can help the patient develop confidence and education in controlling their body in the water. Aquatic treatments are designed to address deficits discovered in the evaluation. All treatment choices should utilize the unique water properties that provide buoyancy, resistance, and hydrostatic pressure to the body.

For patients unable to use the stairs, an ADA-compliant pool lift chair should be available.

For patients unable to use the stairs, an ADA-compliant pool lift chair should be available.


Buoyancy, in simple terms, is the upward lift felt by your body while in the water; it is opposite to the force of gravity. It is the property utilized when a patient needs more support from the water to unweight the body or painful joints. The effect of buoyancy increases as the depth of water on the body increases or as flotation is added to the body. For reference, when a person is standing in a water level at the patient’s umbilicus, weight bearing is reduced to 50% body weight; at the level of the xyphoid process, weight bearing is 25% to 30% body weight; and at top of the shoulders, only 10% body weight. For strengthening exercises, using the depth where the patient has the most postural control and least pain is most beneficial. If no weight bearing is desired, use of a flotation device in deeper water can be used. Exercises in deep water may use pool noodles or a flotation belt for hanging traction, relaxation, or exercises combined for arms, legs, and core. Pools with varying depths provide greater options for the therapist.


Viscosity is the water property that provides resistance to a body’s movement. The speed of movement determines the amount of resistance; faster movements of an extremity require greater strength and greater involvement of the core to keep the body stable. Water walking, for example, requires strength not only from the extremities, but from the core muscles for trunk and postural control. Walking pace, arm swing, step size, and direction of walk can be adjusted to hone in on the best dynamic lumbo pelvic stabilization challenge for the patient, especially those with any low back or lower quarter problems.

Use of aquatic equipment such as paddles in the hands, or float wraps above the ankles, can increase resistance by creating greater drag when moved through the water for shoulder strengthening, or resisting buoyancy and drag during hip motions, respectively. Small, repetitive opposing movements used throughout a range of motion can provide a rhythmic stabilization technique. It is important to recognize a patient’s strength and control is greatly challenged at the point when the body or a limb moving in one direction reverses direction. The patient should use a speed of movement that shows good control in overcoming the inertia created by the initial direction of movement. This concept is often utilized for exercise progressions; educating the patient in modifying the pace for best control of posture and limbs will protect joints from uncontrolled forces, and improve muscular stability.

Hydrostatic Pressure

The last water property for this discussion is that of hydrostatic pressure on the body. Water’s density provides a force in all directions toward the body surface. Since hydrostatic pressure increases with increasing water depth, the deeper the body is in the water, the greater the hydrostatic pressure. In deep water, a patient supported in pool noodles vertically will have the greatest hydrostatic pressure on the lower extremities. This property can help decrease swelling in the legs. Hydrostatic pressure also provides support to joints needing greater stability. Again, pacing is important in controlling resistance if joint instability is an issue.

Physical therapist instructs a patient about core stabilization without compensations. The patient is using hand floats to assist slow, functional movement while maintaining good stabilization.

Physical therapist instructs a patient about core stabilization without compensations. The patient is using hand floats to assist slow, functional movement while maintaining good stabilization.

Aquatic Experience and Training

Aquatic PT has wonderful benefits for the patient, including less pain, a safe form of exercise, and the opportunity to experience a freedom of movement they often do not have on land. Working in an environment where a patient is able to use muscles of ambulation at a reduced challenge allows strengthening for those muscles, as well as a way to re-establish the correct gait sequencing pattern. A patient benefiting from aquatic PT may continue with a water exercise program at their local YMCA or community center, or participate in other aquatic exercise opportunities such as classes in water aerobics, water-based dance, or deep water workouts, to name a few. The Arthritis Foundation sponsors low-impact aquatic exercise classes at many YMCAs, instructed specifically for persons with arthritis.

For the clinician interested in seeking a special certification in aquatic therapy, there are different options. Whereas the American Board of Physical Therapy Specialists (ABPTS) does not recognize a certification with specialty in aquatic physical therapy, the APTA does offer the Certificate in Aquatic Physical Therapy Clinical Competency (CAPTCC). Upon completion of coursework and demonstration of aquatic skills, the aquatic section of the APTA informs, “the CAPTCC provides PTs and PTAs with a comprehensive study of the fundamental knowledge, skills and abilities necessary to provide safe evidence-based patient care using the aquatic environment.”

One may also consider The Aquatic Therapy Rehabilitation Institute (ATRI) and its educational opportunities, including attention to evidence-based practice. ATRI offers a certification upon passing a comprehensive examination with continuing education requirements to maintain status. Aquatic Exercise Association (AEA) also has comprehensive certification, and coursework as well.

Though aquatic therapy is not new, not all PT clinics are able to provide these services. Limiting factors can often be cost, having space for a therapy pool, or the ability to coordinate use of a local pool. If a new therapeutic pool is in the future for your clinic, there are several options to consider. Pools are available in a variety of sizes and designed for in-ground or above-ground use. Among the therapeutic features built into some of the pools currently on the market are variable-depth floors, underwater treadmills, resistance jets, well-placed railing, and video cameras used at a treadmill for live video feedback to improve gait. Other choices include stairs with railing and ADA-compliant chair lifts for the patient who needs greater assistance into and out of the pool. Some pools have a floor that can rise to the water surface for easy access. A patient can stand at a rail, or if using a wheelchair, can roll onto the elevated floor. Using a control, the floor can be lowered to the appropriate level for the patient.

Aquatic therapy certainly is another “tool for the tool belt” that can help patients regain function, but also considers the experience for the patient affected by limited function, and the psychological benefit of feeling the freedom of standing, or walking. For some patients, this specialized type of therapy can help turn the corner to a healthier lifestyle. RM

Anne Plattenburg, PT, MPT, has worked in the outpatient setting as an aquatic and clinical physical therapist for 11 years. She received a master’s degree in physical therapy from Andrews University in 2004, and her bachelor of science from the University of Dayton in 1988. Plattenburg currently works for Premier Health at Miami Valley Hospital in Dayton, Ohio. For more information, contact [email protected].