13

Aquatic Therapeutic Exercise

Benefits and Purpose Benefits and Purpose of Aquatic Therexof Aquatic Therex

Exercise sometimes possible sooner in water than on dry land

Non weight bearing

Offers total exercise program: cardiovascular conditioning, flexibility, strength, muscular endurance

Specific GravitySpecific Gravity

Also called relative density

Specific gravity of water = 1

Ratio of an object’s weight to the weight of an equal volume of water

Average specific gravity for body = 0.95-0.97

For human body, depends on lean and fat mass and distribution of body fat

Archimedes principle: A body partially or fully immersed in a fluid will experience an upward thrust of that fluid that is equal to the weight of the fluid the body displaces.

BuoyancyBuoyancy

Archimedes principle

If body has specific gravity of 0.95, 95% of body will be submerged and 5% will float

A body with a specific gravity of less than 1 will float because weight of water displaced is less than weight of body

Center of BuoyancyCenter of Buoyancy

The center of gravity of the displaced fluid and the point at which the buoyant force acts on the body

When in equilibrium, the center of buoyancy and the center of gravity are in vertical alignment with each other and the body is balanced

HydrodynamicsHydrodynamics

Viscosity

The resistance to movement within a fluid that is caused by the friction of the fluid’s moleculesInfluenced by cohesion, adhesion, surface tension

(continued)

HydrodynamicsHydrodynamics

Drag: the water’s resistance to a body that is moving through it

Form drag

Frictional drag

Wave drag

Hydrostatic PressureHydrostatic Pressure

Pascal’s law: Pressure from a fluid is exerted equally on all surfaces of an immersed object at any given depth

For every foot of submersion, water pressure increases by 0.43 psi

The more deeply the object is immersed, the greater the pressure

Positive impact on edema

Pascal’s LawPascal’s Law

Reprinted from Bates and Hanson 1996.

Weight Bearing in WaterWeight Bearing in Water

The more deeply the body is submerged, the less weight is borne by the lower extremities.

Females’ center of gravity is lower than males’: affects percentage of body weight borne at different depths.The faster a person walks in the water, the higher the weight-bearing percentages.

Weight Bearing in WaterWeight Bearing in Water

Reprinted from Harrison, Hillman, and Bulstrode 1992.

Aquatic EquipmentAquatic Equipment

Safety equipment

Resistive devices: used to increase muscle strength/endurance; increase surface area, require speed, add buoyancy or weight

Assistive devices: help stabilize body, maintain buoyancy, assist in motion

Cardiovascular devices

Indications Indications for Aquatic Therexfor Aquatic Therex

Pain, edema, muscle spasm, loss of motion, weakness, limited endurance

Maintaining cardiovascular conditioning or normal status of uninvolved extremities

Restricted weight-bearing status

AdvantagesAdvantages

Can be performed even if weight bearing is restricted

Buoyancy reduces joint compressive forces

Warmth of water can relax muscles, relieve pain

Reduces weight bearing while allowing muscles to continue to function properly in the gait sequence

AdvantagesAdvantages

Can promote body awareness and balance

Can be used early in rehabilitation program, helping to prevent deconditioning

Can relieve or reduce pain due to immobilization or edema

Precautions Precautions for Aquatic Therexfor Aquatic Therex

Fear of the water

Conditions such as diabetes, cardiovascular disease, seizure disorders

Medications

Ear infections

Never allow patient in pool unattended

Contraindications Contraindications for Aquatic Therex for Aquatic Therex

Contagious infection

Temperature of 100° F or more

Severe cold or flu

Urinary tract infection

Open wounds

Application Application of Aquatic Principlesof Aquatic Principles

Hydrostatic pressure: more advantageous to exercise swollen extremity in deep water

Greater resistance achieved through

longer lever arm, straighter extremity

increased speedmoving object at surface of water or with increased surface area

Aquatic Exercise Aquatic Exercise ProgressionProgression

Early

Use buoyancy equipment for increased range of motion.

Do gait training in deep water.Use resistance exercises without equipment.

(continued)

Aquatic Exercise Aquatic Exercise ProgressionProgression

Mid

Emphasize restoration of muscle strength and endurance.

Use drag to increase resistance.Add resistive equipment.

(continued)

Increase reps and sets.

Aquatic Exercise Aquatic Exercise ProgressionProgression

Advanced

Focus on restoration of ABCs of proprioception

Gait training more intense and varied

Hopping, jumping, etc.

(continued)

Eyes open, closed.

Increased intensity for strength

Aquatic Exercise Aquatic Exercise ProgressionProgression

End phase

Mimicking skills and demands of sport

Aggressive coordination, agility, speed activities

Plyometrics

Benefits Benefits of Deep-Water Exerciseof Deep-Water Exercise

No weight bearing and no impact forces

Forces of gravity on a submersed body are minimal

Can help maintain cardiovascular fitness and strength

Exercises essentially concentric

Correct Vertical AlignmentCorrect Vertical Alignment

Correct Position Correct Position for Deep-Water Runningfor Deep-Water Running

Refraction of LightRefraction of Light

Determining Depth Determining Depth of Waterof Water

Patient’s confidence in the water

Patient’s weight-bearing status

Goals of the exercise