Resistance Swimming And The Pressure-Driven Swimming Machines

Swimming is an exercise that is good for people of all ages and of most any physical condition. It can be performed with little risk of strain. In turn, there is a form of swimming exercise that is used as a form of training for athletes and also for use as a therapy. This is known as resistance swimming.

As a form or method of exercise for swimmers, resistance swimming is useful when training for any of the swimming styles or strokes. Its simplest form makes use of a restraining device that keeps the swimmer rather fixed in a particular position while swimming. Swimming machines are used to create an "artificial" flow of water against which the swimmers perform the exercise.

Thus, resistance swimming is synonymous to the use of any of the various types of swimming machines. The pressure-driven swimming machines are examples of these. Included here are the bare propulsion system and the swim spas (single- and dual-zone systems).

Pressure-driven swimming machines work on at least one pump. They artificially set the water in motion. A 3-horsepower (2.24-kilowatt) motor discharges water at the rate of 13 liters per second, or 206.05 US gallons per minute. Some models, which are attached to pools, work simply as a propulsion system. Here, an explosive force of motion is produced by means of a metal-water reaction, which is made possible by the action of a high alternating magnetic field on metal fuel slurry.

Other more convenient models are those that actually come in the form of a spa. These models often are fiberglass shells fitted with a number of pool pumps that set the water in motion. One example of a typical model consists of an exercise pool with swim jets at one end. In addition, it has at least one seat equipped with a massage jet at the other end.

Open water swimming and triathlon competitors prefer to use these pressure-driven swim spas in their training because the turbulence produced in these machines simulate that which they usually encounter in the sea during actual competition. This, the athletes say, improve their endurance and overall fitness.

Another model of the pressure-driven swim spa, called the dual-zone system (developed in the 1980s), consist of two pools. Water temperature in each of the pools can be set at different degrees. Also, the kind of chemical that may be used for each of the pools can be varied. In the therapeutic pool, for instance, bromine is used and water temperature is moderately hot, which is ideal for massage and/or relaxation. The athletic-training pool, on the other hand, uses chlorine, with water temperature suited for vigorous exercise.

The most basic kinds of swimming machines are those called countercurrent swimming machines. A machine of this type is made up of a tank, with length two times and width one and a half times those of an average individual (arms and legs extended). The swimmer swims sans restraint against the water's movement artificially created by a propeller, paddle wheel, or jet.