AquaJogger ® - Water Fitness Glossary

Why Water Exercise Differs from Land Exercise

Water makes up 70 percent of the human body, so it's not surprising that when the body is immersed in water many positive physical changes occur instantly.

From increasing circulation to lowering blood pressure, water's unique properties provide an invigorating and joint-friendly environment. In water, gravity is almost nonexistent, yet resistance can be increased up to 42 times that of air-making water an ideal low-impact and total body conditioning workout. Always consult your doctor before undertaking water fitness workouts.

1. Action/Reaction. For every action there is an opposite and equal reaction.

Water pushes back equal to the energy exerted against it. With every movement, water's natural resistance provides a time-efficient workout while toning the muscle pairs equally. In water, the amount of resistance can be instantly adjusted by the individual's own exertion to be as challenging or light as desired. Couples can workout together-each at their own pace-and water fitness classes can accommodate a wide range of skills and fitness levels.

2. Buoyancy. An upward thrust exerted by water on a body which acts in the opposite direction to the force of gravity.

Water's buoyancy virtually eliminates the effects of gravity-supporting up to 90 percent of the body's weight for reduced impact and greater flexibility. For example, a 140-lb. woman weighs only 14 lbs. in water. Water acts as a cushion for the body's weight bearing joints, reducing stress on muscles, tendons, and ligaments. As a result, aquatic workouts are low impact and can prevent the injury, strain, and re-injury common to many land-based exercises. Wearing a buoyancy belt suspends the body comfortably with the neck and shoulders above the water for an effective, low-impact, deep water workout.

3. Eddy Drag. Occurs when unstreamlined objects move through the water impeding the flow and-if the speed of movement is increased-creating rapid and random turbulence in the water.

Increasing the speed and/or surface area of a moving object in water results in increased drag against that object. Eddy drag can be maximized during a water workout by cupping the hands to create little "eddys" or whirlpools around the movement. Muscle strength and toning increases as the body works harder and faster against the waters resistance.

4. Hydrostatic Pressure. Fluid pressure is exerted equally on all surface areas of an immersed body at rest at a given depth.

Water exerts a force on the body even when it is stationary. The pressure of the water helps the heart circulate blood by aiding venous return blood flow back to the heart. This assistance to the heart accounts for lower blood pressure and heart rates during deep water exercise versus similar exertions on land. As a result, water exercise may be one of the safest and most useful fitness programs for cardiac patients, Hydrostatic pressure also helps reduce swelling for many and can accelerate the healing process by increasing the volume of nutrient rich blood being circulated throughout the body, allowing many people with injuries or arthritis to exercise comfortably.

5. Resistance. Due to viscosity, drag forces and frontal resistance, water provides resistance proportional to the effort exerted against it.

Experts say resistance to movement can range from approximately four to 42 times greater in water than air, making water a natural and instantly adjustable weight-training machine. Unlike most land-based exercise, water can strengthen both sides of the muscle pair simultaneously. For instance, an arm curl works both biceps and triceps, because there is resistance to the movement in both directions of the exercise. Water's resistance can be increased with speed and/or surface area and is proportional to the effort required to move against it. Adding water fitness equipment can increase resistance to strengthen and tone the muscles.

6. Specific Heat. The ability to absorb and communicate large quantities of heat. It is much harder to raise the temperature of water than air. A layer of water around the body does not insulate, but instead conducts heat.

The temperature of pool water (approximately 83 degrees) decreases the load on the heart by assisting in cooling the body. Evaporation of sweat is one of the most important ways the body loses heat after immersion in a pool. Heat is lost much faster in water than air, allowing far greater training intensities and durations. The water's ability to cool the body is also a benefit far people who tend to overheat while exercising, and in conditions such as pregnancy or multiple sclerosis, where maintaining a lower core body temperature is very important.

7. Specificity. Human performance is highly task specific, so both the metabolic and bio mechanical requirement of the activity must be considered when training to enhance performance.

Activity in the water can be designed to target specific anatomical sites for strengthening, rehabilitation, and injury prevention. Land-based activities, such as running, can be closely imitated in deep water to enhance performance without the impact. This allows participants to train while injured and is a very useful cross-training technique. Similarly, practical daily movements such as walking, lifting, or reaching can be incorporated into a water fitness workout to enhance functionary and range of motion.

8. Viscosity. The frictional resistance of water molecules which comes from two main properties- cohesion and adhesion. Cohesion is the attraction of molecules for one another from the same material. Adhesion describes the attraction of molecules of different material for one another.

Water molecules cling to each other and to the body as it moves, creating both resistance to water movement and a remarkable sensory experience. Immersing the skin (the body's 1argest organ) in water alters the signals of pressure, pain, temperature, and pleasure to the central nervous system, allowing reduction of stress-related symptoms such as high blood pressure. The water's full-body massage action provides a vigorous, yet deeply relaxing and pain-free workout.

Source: www.aquajogger.com

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