Water exercise remains a popular and viable alternative to land-based modes of fitness training. A properly designed water workout incorporates most if not all of the components of a typical land-based workout, resulting in measurable gains in cardiorespiratory fitness and the attainment of improved health and wellness including improved body composition, muscle endurance and flexibility.
The purpose of this article is to highlight the effectiveness of deep water as an alternative to land-based core training.
Buoyancy and Body Composition
Water fitness is often undervalued as a stimulus for performance enhancement based on a common perception that although comfortable, it is an ineffective way to expend energy and offers minimal impact on overall fitness. To the contrary, deep water training transforms this perception into one of a dynamic and intense core abdominal fitness regimen.
A key component of deep water work is the concept of buoyancy. The use of water as a training medium requires manipulating buoyancy, a factor that opposes gravity. This is a concept that tends not to be well understood by fitness processionals who predominantly teach land-based fitness workouts.
The Archimedes Principle (AP) defines buoyancy as “any object that is wholly or partly immersed in a fluid, is buoyed up by a force equal to the weight of the fluid displaced by the object.” In other words, a direct relationship exists between the weight of the submerged body and the amount of fluid being displaced. Additionally, the effects of buoyancy are increased as the lungs become submerged.
Participants in an aquatic environment who have a low percentage of body fat have a tendency to be less buoyant and have a greater likelihood of sinking. Alternatively, participants with a higher percentage of body fat will be more buoyant and are more likely to float. Participants exercising in a deep water environment having either type of body composition will have a propensity to “turn and roll” until their body finds a place of equilibrium. The neurological processes must find alternate paths for the successful completion of this new set of tasks, whether it be just staying upright and vertical or performing more complex movement patterns of prescribed exercises.
The basic principles of exercise science apply in deep water, but because the environment is so different from land and shallow water, the training methods used to create effective exercises are unique to the suspended environment.
Deep water exercise adds tremendous challenge to the muscles that support the spine. Since participants are not anchored to the pool bottom like they are in shallow water or land-based programming, the buoyancy creates an inherently unstable working environment. Exercisers must engage the stabilizing muscles of the core more aggressively to maintain vertical alignment and proper body positioning.
The diminished effect of gravity in deep water plays a crucial role in demanding that each participant strive to achieve optimal posture and spinal alignment. Buoyancy and the necessity to constantly balance and stabilize the body results in the core muscles working at higher intensities. Effective core training can be achieved through deep water exercise design that promotes a balance by incorporating both the physical properties of water and the unique dynamics of the buoyant environment.
Open Chain Exercise Selection
When the weight of the submerged body is equal to the weight of the fluid displaced, the body’s center of gravity (the hips) and the body’s center of buoyancy (the chest/lungs) will be in vertical alignment. However, if this equation is not equal, then the center of gravity and the center of buoyancy will not be vertically aligned, and the participant will struggle to stay upright and vertical in the water.
During deep water exercise, both safety and exercise effectiveness are increased when the center of gravitational balance is aligned with the center of buoyancy. Humans are bipedal and the erect stance is fundamental to healthy function. Deep water exercisers must learn how to balance between these two points for successful training results to occur. Since there is no stable base of support in deep water, the abdominals have to work to maintain a “land like” upright posture, constantly firing the muscles of the core.
In deep water, fluid dynamics are exaggerated. A movement in deep water causes a more pronounced reaction, so balance is critical. Jogging or cross country ski exercises are easier to perform because both sides of the body match in their sagittal plane motions due to the symmetrical movements. Although effective to stimulate the core muscles, those who wish to take advantage of core training opportunities in the water should perform asymmetrical exercises. Asymmetrical movements are much more challenging because the uneven movements of the legs and arms cause the torso to shift away from a vertical, upright posture. As the participant feels the body going off balance, an attempt to maintain a vertical working position is made. This forces the muscles of the trunk to work harder, thus encouraging core muscle recruitment.
The most common performance error in deep water exercise is poor body alignment. Another common error is a marked lack of coordination and inability to maintain balance. Individuals who are unskilled and/or unfamiliar with deep water exercise often lean forward at the waist in an effort to compensate for the dynamic change in their center of balance. This posture makes deep water exercise easier to perform, but it inhibits the proper muscles from doing the work. By maintaining an upright, vertical and aligned posture, participants enhance frontal resistance, core muscle recruitment and exercise intensity.
Examples of exercises that are appropriate for recruiting the muscles of the core in deep water include:
- Mogul jumps
- Single leg jacks
- Knee lifts
- Inner thigh lift/ankle reach in front
- Backward jog
- Vertical flutter kicks
- Leg curl/hamstring curl
- Single leg front kick/Karate kick
Equipment can affect the intensity of the workout as well as add variety, provide additional support and give the participant’s the opportunity to progress their exercise selection. Although a number of equipment options for water exercise exist, those specifically important for deep water exercise programming include buoyancy equipment.
Equipment that floats allows the participant to work in a suspended position. Many water fitness professionals agree that some type of flotation device or buoyancy aid is necessary in deep water to promote a participant’s safety and comfort. While it is true that people with swimming skills can stay afloat, few can sustain a vertical posture in deep water without experiencing eventual fatigue. Without added flotation, a large amount of energy must be expended to keep the head above water, and this may put your participants into a “survival mode” just to stay upright. Equipment such as buoyancy belts, dumb bells, webbed gloves, ankle cuffs, noodles and/or other flotation devices are recommended. This equipment will assist with buoyancy to support and enhance upright posture as well as provide for optimal range of motion.
Equipment that excessively promotes buoyancy will make it difficult for exercisers to maintain their center of balance and allow them to master control of their movements. Difficulty pushing with force through the water is also likely to result. A loss of biomechanical balance is often the result of the participant using the same movements over and over again simply to stay afloat. On the other hand, too little buoyancy affects the participant’s ability to maintain a vertical position in the water.
A key awareness in the use of buoyancy equipment is the placement and positioning of the buoyant equipment on the immersed body. A flotation belt is recommended, and its use should be determined on an individual basis. A properly fitting buoyancy belt will allow an individual to maintain proper vertical alignment with the head held above the water when in a motionless position. With proper flotation, participants can focus their energy and efforts on full range of motion movements that utilize all the major muscles in all planes of movement.
The unique properties of the deep water environment require thought and use of common sense when developing safe and effective deep water programming with the goal of producing positive training results. Understanding the various ways in which the buoyant environment impacts human movement and the body’s response to exercise can prepare a trainer to develop deep water skills and lead clients through effective deep water exercise selection.
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