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Open Water Natation

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Swimming for Fitness

Open Water Swimming


Swimming is an excellent exercise for overall fitness; aerobic endurance, power, strength, and flexibility are all enhanced by swim training.

It is generally gentle on the joints and provides excellent cross training for running and other gravity-intensive forms of exercise by providing load-bearing joint rest. However, training must be specific for the anticipated operational environment, including cold water acclimatization, lane swimming, etc.

This section will give you the tools to improve your swimming skills, thus enhancing your overall fitness.

We will examine both open water and pool swimming.

Wet Suits

Open water swimming may require thermal protection for safety. Males in
particular may be susceptible to hypothermia and the first symptom in an open water
swimmer may be unconsciousness from cardiac arrhythmia. Thermal protection in
swimmers means a wet suit worn over an anti-chafing shirt.

Wet suits designed for open water swimming are generally of a Farmer John design
with the arms free for stroking. In all but the coldest water, a 1/8” wet suit is best for surface swimming. Unlike diving, there is no need to factor in the loss of insulation due to compression of the neoprene with depth.

Anti-chafing shirts are generally made of nylon without elastic properties. Worn under the wet suit, the nylon shirt allows arm strokes and head rotation without getting chafing from the wet suit. If you don’t use anti-chafe shirts, then this would not matter.

Hood, Gloves and Booties

Good open water swimming hoods allow the head to be turned with minimal
chafing. Thermal protection is not as good with the neck exposed. A good
hood preserves a great deal of the swimmer's heat.

Gloves may have webbed fingers to allow sidestroke pulling to be more efficient.
They work great for freestyle, too. Neoprene web gloves are popular
and work like paddles.

Thin 1/8” booties without soles maximize the power delivered by the swimmer's legs to the fins.

Fins and Fin Selection

The main principle of fins is to increase the surface area of the foot.

There are three factors to keep in mind when you are selecting a fin; the specific
design characteristics of the fin, the physical attributes particular to your body, and
operational constraints. Fins, by increasing the surface area of the foot, serve to magnify the thrust delivered by the legs. Kicking with fins involves a forward stroke and a backward stroke.

Always remember that the fit of the fin is critical. If the fin is too tight, the finbox may make your foot cramp up and more susceptible to cold. If it is too loose, energy is lost in the slop between foot and footbox; slop also translates into foot chafe!

Booties provide grip for the foot within the footbox and the neoprene acts to even out areas where stress is concentrated.

Specific Design Characteristics of Fins

If your ankle range of motion is inherently limited, long fins will assist in transmitting lower extremity to the water.

If your ankles are inherently flexible, short fins may be more efficient as well
as less stressful on relaxed ankle joints.

Your natural kick frequency will also influence your choice of fin stiffness
and size. Larger sizes and stiffness produces a slower rate of kicking, while
short flexible fins allow a higher kick rate.

Face Masks

A face-mask is required for swimming as prolonged
exposure to salt water and/or stinging marine organisms may cause eye irritation or injury.

Open Water Training

There is no substitute for ocean or lake swimming. Training in open water will force you to swim straight and develop a cycle of breathing that allows you to look forward in order to navigate.

To put it simply, in order to improve your technique and ability to swim in open water, you need to do it regularly. Substituting training in the open water for swimming in a pool will not act as a good replacement.

While swimming in a pool will improve your cardiovascular fitness and swimming technique, it will not help you adapt to open water swimming.

Regular training in open water will allow you to become accustomed to external factors such as currants, aquatic plants and marine life.

Water Temperature Issues

Although the work of swimming generates heat, there is heat loss created by movement of the swimmer into new “unheated” cold water. Thus, open water swimming may require various combinations of passive thermal protective gear, in particular, wet suits.

The determinants for passive thermal protection are the temperature, the length of the swim and the effort level.

It is important to remember that wet suits operate by allowing the body heat to be
transferred to a layer of water caught between the body and the neoprene material of the suit. Convective heat loss from the swimmer's body is greatly reduced by this mechanism and as a result, swimming at a high effort while wearing a wet suit allows the swimmer to generate and retain heat.

Special Open Water Training Issues

It is easy to have chafing from the wet suit around the arms and also for the fins to
chafe. Get thin booties without soles for fin use and consider using some vaseline or
aquaphor ointment for other chafe points.

If you swim regularly in cold water, your body will undergo some adaptive changes.
This will increase your tolerance to some extent. You will also begin to actually crave fatty foods, an instinctual tendency of cold water swimmers to want extra body fat to protect them! This is a natural adaptation, but this may be undesirable for your running and overall fitness.


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