Crawl: Technical Sheet

 Introduction

The crawl - erroneously called freestyle - involves alternating and cyclic movements of the upper and lower limbs; a lateral type of breathing is inserted on the action of the arms , which can be carried out on one side only, or alternatively to the right and left (usually every 3 strokes you breathe with Lifeguard Classes Near Me.

Note : when you come out with your face to breathe, it is necessary to keep the respective shoulder as an optical reference point , in order to avoid raising the head excessively and slowing down the swim).

The position assumed, both prone and  supine , is conditioned by the lower limbs, whose mass constitutes about 40% of all  body weight with American Lifeguard Florida.

While, in fact, the upper part, thanks to the floating bag of the lungs , remains rather raised, the legs tend to go down.

This sinking occurs to a greater or lesser extent based on the specific weight, which, if it favors the lighter ones, certainly creates some problems for those whose limbs are made heavy by a considerable bone and musculature .

The thrust of the foot also receives an upward (as well as forward) response from the water which is useful for floating both the limbs and the whole body, thus favoring a more raised position and a better hydrodynamic attitude.

The best position to be able to move forward in the water is that which allows the swimmer to remain horizontal and as high as possible; this allows to minimize the resistance offered by the water.

The propulsion of the lower limbs, together with the action produced by the arms in the support phase, allows the whole body to rise, making the swimmer assume a more hydrodynamic position, through which he can "slide" better.

Data sheet

Crawl movement

Alternating and cyclic.

Body position in the crawl

Prone; in sprints the body tends to be well lifted and almost glide on the water; in long distances, however, it remains a little more immersed.

Upper limb movement in the crawl

1. Aerial action;
2. Underwater action.
3. Air action has two functions:
4. forward carry of the limb;
5. muscle refreshment .

The aerial movement if carried out with  the elbow flexed reduces lateral displacements of the pelvis and lower limbs; guarantees greater energy recovery.

The underwater action is distinguished in: support / grip, traction and thrust.

The action is always active, albeit with a different result in the advancement, depending on how the hand directs the thrusts.

The action of the hand develops according to a curvilinear trajectory (to take advantage of the upward thrust; to find steadier water by changing the direction of application of the force ; to apply the force longer.

At the end of the support / grip phase, the arm flexes at the elbow to take advantage of a more advantageous lever and to develop an action (if viewed from the side) more parallel to the line of advancement.

The elbow in the traction phase must be high with respect to the hand; targets:

to make the hand itself perform a useful rowing action (Bernoulli);

also involve the forearm in pushing backwards.

Breathing in the crawl

It is inserted on the action of the arms every single cycle, after several complete cycles, or to the right or left every 3 ... 5 ... strokes.

The swimmer should exhale fully under water by doing the following:

to respect a moment of waiting, to stay longer with full lungs;

to delay the rotation of the head for a better hydrodynamic attitude.

Lower limb movement in the crawl

• The useful phase develops in the movement from top to bottom;
• The whole limb is involved in the movement, from the hip to the feet;
• The action takes place completely underwater;
• The depth varies from 20 to 40 cm;
• The flexion of the leg on the thigh can reach up to 110/120 degrees;
• The foot in the descending phase must naturally be extended and rotated inward for better thrust.

Upper and lower limbs relationship in the crawl

the position one tends to assume is the most hydrodynamic that can be achieved in swimming, even if very expensive due to the intense action of the legs;

the latter carry out a mainly propulsive action;

the underwater action of the arms is very wide to allow the insertion of the six beats - the aerial action must be with the elbow flexed;

adequately delayed breathing is very suitable for this type of crawl.

you swim more in the water, so the body's attitude is less hydrodynamic than in the previous interpretation;

increases the stabilizing function of the lower limbs;

the underwater action of the arms is reduced in amplitude and has a higher frequency; aerial action tends to be faster and arm less flexed;