Add Water to the Mix

by: Kenneth Baldwin

Including aquatic fitness in your training package can enhance your clients' programs and expand your client base.

With the number of Americans who are inactive and/or overweight steadily increasing, personal fitness trainers (PFTs) face many challenges. Meeting these challenges requires the ability to cater to a broad client base, as well as a determination to keep up-to-date with current industry trends and research.

Successful PFTs, like successful businesspeople in any industry, continually look for ways to provide extra services to separate themselves from the competition and attract clients. For PFTs, aquatic fitness completes the training package and provides that competitive edge.

A New Look at an Old Trend

Aquatic fitness has been around for many years as a group fitness program. Since water’s buoyancy makes this exercise mode low impact, it has traditionally been popular with elderly or obese clients and those with conditions such as inflexibility or arthritis. This may be one reason why athletes—and even the general population—have sometimes perceived aquatic exercise as a nonchallenging activity to be used only for relaxation or injury rehabilitation. But that perception is changing.

PFTs are now beginning to use water exercise in their one-on-one training programs, taking advantage of the benefits of water to fulfill clients’ needs for motivation, variety and results.

The Benefits of Water Exercise

A properly designed aquatic exercise program provides everything required for physical fitness—including cardiovascular, strength, power, endurance and speed training. Water exercise also provides the following benefits:

  • The gravity-reduced environment decreases the load and stress on joints while providing resistance and allowing for increased range of motion (ROM) and full joint action. As a result, aquatic exercise can be used not just with injured clients but also to prevent injuries in the first place.
  • The medium of water makes it easy to increase and decrease intensity to effectively tailor exercise to individual needs and abilities. In addition, varying water temperature helps individualize workouts. Warmer water allows greater relaxation and less spasticity of muscles and joints, reducing discomfort for exercisers who are in injury postrehab. Cooler water reduces heart rate and prevents the body from overheating, which allows healthy participants to exercise longer without exhaustion.
  • Water’s hydrostatic pressure decreases blood pressure, allowing for greater exercise tolerance before fatigue sets in.
  • The fluid environment permits exercise in more than one plane of movement (vertical and horizontal).
  • The properties of flotation, buoyancy, resistance, drag and change of direction can increase the strength benefits of exercise while enabling clients to work out longer.

Learning the Basics

Designing an effective water exercise program requires two areas of basic knowledge. The first one, a knowledge of simple biomechanics and how the muscles and joints work through different ranges of motion, is required of all PFTs. But to be an aquatic exercise trainer, you also need a familiarity with basic physics and an understanding of how the properties of water interact with ROM, overload and intensity. In addition, to use aquatic exercise for clients in postrehab, you should have an in-depth knowledge of physiology, anatomy and kinesiology. Training or interning with a physical therapist would be particularly helpful.

Although movement on land and in the water is the same in principle, the properties of water totally change the way the body performs movement. For example, a front kick or a side travel movement is slower in water than on land, owing to water’s buoyancy, drag and resistance properties.

Water is approximately 800 times heavier than air (Kravitz & Mayo 1997). Water does not have resistance properties in itself, but when a solid object is immersed in water, resistance impedes movement. The hydrostatic and hydrodynamic principles for water movement are governed by the following four principles, or laws, of physics (Walding, Rapkins & Rossiter 2004):

1. Archimedes’ Principle of Density and Buoyancy. Archimedes’ law states that any body completely or partially submerged in a fluid at rest is acted upon by an upward, or buoyant, force. The magnitude of this force is equal to the weight of the fluid displaced by the body. According to this principle, the amount of movement, water depth and weight of the object will affect motion in water.

2. Pascal’s Principle of Hydrostatic Pressure. According to this principle, the pressure exerted on the surface of a body submerged in a fluid at rest is equal on all sides at a given depth. Performing the same exercise in different water depths will result in changes in pressure, as well as different applications to the working muscles.

3. Bernoulli’s Principle of Turbulence. This principle affirms that turbulence increases the intensity of the workout by creating a buildup of resistance around an object. When a body moves through water, pressure builds up in front of the body, and a negative pressure (turbulence) is created behind the body, dragging it backward. Employ-ing longer lever lengths and working in deeper water create more drag and resistance; a more streamlined body produces less drag and resistance.

4. Bouguer’s Principle of Stability and Balance. This principle explains that each object has a center of gravity, which is the point around which all gravitational forces are equal. This position will vary with changes in the shape and position of the object. Therefore, lengthening the lever will increase work load, and changes in speed will change the exercise effect.

An understanding of these laws of physics clarifies the conditions that change the effect of exercise in water. These conditions include buoyancy; the starting position of the body; the length of the moving part; and changes in speed, body positioning and the degree of added resistance (from equipment). Of course, with the exception of buoyancy, all these factors also need to be taken into consideration when analyzing movement on land.

Potential New Target Markets

The suitability of water fitness for aging Baby Boomers and overweight clients is obvious. But here are some other target groups to consider.

Individual Athletes and Sports Teams. No matter what sport they participate in, athletes always have a need for activity that is different from their usual routine. They may use aquatic exercise to build on their strength and speed in the preseason, to provide nonimpact cross-training or postrehabilitation during the season and/or to “change up” their periodization program postseason with a totally different training mode.

People With Disabilities. Clients who have difficulty performing activities on land may benefit from the properties of water and, with assistance, enhance their everyday activities.

Kids. Water creates a fun environment that allows kids to complete a task without thinking of it as work.

Injured Exercisers. By partnering with physical therapists, you can design postrehab water exercise programs to help injured clients improve ROM, flexibility and strength before placing the joints and muscles under load in a weight training situation.

People With Limited ROM or Flexibility. The properties of buoyancy and flotation allow clients to isolate muscles and improve ROM to a greater extent in water than on land.

Increasing Liquid Assets

Aquatic fitness offers a great opportunity to expand your income stream and provide a unique service to your clients. Building the necessary skill sets takes time and a great deal of passion, but the rewards are well worth the effort. (Also see “Partnering With an Aquatic Exercise Instructor”.)


Kravitz, L., & Mayo, J.J. 1997. The physiological effects of aquatic exercise: A brief review. www.drlen; retrieved Jan. 4, 2007.

Sanders, M.E., & Kennedy, C. 1997. To improve your

fitness program, just add water! www.sandford

ness.html; retrieved Dec. 27, 2006.

Walding, R., Rapkins, G., & Rossiter, G. (Eds.). 2004. New Century Senior Physics: Concepts in Context (2nd ed.) (chapter 7: Hydrostatics and Physics of Fluids). Melbourne, Australia: Oxford University Press.

IDEA Fitness Journal , Volume 4, Issue 3

© 2007 by IDEA Health & Fitness Inc. All rights reserved. Reproduction without permission is strictly prohibited.

About the Author

Kenneth Baldwin IDEA Author/Presenter

Ken Baldwin is an international presenter and is currently the education and products manager for QPEC, a company dedicated to CEC workshops for fitness professionals in Australia. Certifications: ACE...