Newsgroup: it.sport.nuoto
Titolo: della Manaodou e della sua gambata stile

bella e brava la giovane, ma non era di questo che volevo parlare, bensì
della gambata stile dei fondisti.
Si è già parlato: la regola sarebbe sei gambate per ogni ciclo di
bracciata per i velocisti e due gambate per ciclo di bracciata per i
fondisti. Si è anche detto nel passato che anche questa - come ogni
buona regola - è fatta per essere derogata; e infatti c'è l'austrialiano
(come diavolo si chiamava?!) che si fa i 1500 sl menando le gambe come
si fa in un cinquantino.
Ma la tecnica della gambata del fondista (2+2) non l'ho ancora capita.
Mi è sembrato di vedere la Manaodou (ecco che c'entra qualcosa) che
batte la gamba destra quando entra in acqua il braccio sinistro, e
viceversa. Ma si fa così o è un'interpretazione personale della  bella e
brava Laure?
-- 
Tutti abbiamo forza sufficiente per sopportare i mali altrui.

 brava Laure?
A ma pare che non si incroci, ma che si muovano prima gli arti di un 
lato e poi quelli dell'altro..
-- 
Happiness happens

Ho solo presente l'estrema economia (e l'infinita classe!) del movimento 
gambe di Laure Manaudou, non ho la competenza per definirlo un Two-Beat 
Kick, magari quel che segue può aiutare a identificare la cosa.
Kalì.
Estratto dal Cap.4 - Front Crawl Stroke
---------------------------------------------
Timing of the Arms and Legs
Kicking rhythm refers to the number of leg strokes a swimmer takes during 
each complete stroke cycle. One complete leg stroke consists of an upbeat 
and downbeat. Thus, these two beats have traditionally been considered as 
one when the timing between arms and legs is described. Two armstrokes 
constitute one stroke cycle in the front crawl stroke.
World-class swimmers have used a variety of kicking rhythms successfully. 
The most popular rhythm is the six-beat kick, in which swimmers complete six 
leg beats during each stroke cycle. Other popular tempos are the two-beat 
rhythm and the four-beat rhythm.
The six-beat rhythm is used by most sprint swimmers and a large number of 
middle distance swimmers, but by only a small number of distance swimmers. 
The two-beat rhythm has been used primarily, although not exclusively, by 
distance swimmers. Four-beat rhythms, used less frequently, are still 
popular among a significant number of swimmers. Eight- and 10-beat rhythms 
have also been tried over the years, but they were not successful and have 
been abandoned.
Six-Beat Kick
The six-beat rhythm, illustrated in figure 4.16, includes three leg beats 
per armstroke, or six beats per stroke cycle. This rhythm can best be 
described using the relationship between leg downbeats and the various arm 
sweeps during each stroke cycle. In this respect, one downbeat of each leg 
is coordinated with each of the three sweeps during one underwater 
armstroke. Focusing on the right armstroke, the downsweep of that arm is 
coordinated with the downbeat of the right leg (see figure 4.16a). The 
insweep of the right armstroke is accompanied by a downbeat of the left leg 
(see figure 4.16b), and there is another downbeat from the right leg during 
the upsweep of the right arm (see figure 4.16c). The timing is similar 
during the left armstroke, with the left leg kicking down during the 
downsweep of the left arm (see figure 4.16d), the right leg kicking down 
during the insweep of the left arm (see figure 4.16e), and the left leg 
kicking down again during the upsweep of the left arm (see figure 4.16f).
The coordination between arm sweeps and leg beats just described is so 
precise that the beginning and end of each downbeat of the legs coincides 
exactly with the beginning and end of the corresponding arm sweep. Large arm 
sweeps are accompanied by large kicks, but the kick will be smaller when its 
corresponding sweep is smaller. This probably explains why many six-beat 
swimmers have what appear to be major and minor kicks during each stroke 
cycle.
The six-beat rhythm is so natural that most swimmers perfect it through 
trial and error with little or no instruction. This timing undoubtedly 
contributes to the total propulsive force during each arm sweep. Most 
particularly, the downbeat of each leg that accompanies the downsweep of 
each arm probably plays an important role in reducing swimmers' rates of 
deceleration during that phase of the armstroke. In addition to the 
propulsive force they provide, the leg beats that accompany the insweep 
probably also assist in rotating the body toward the stroking arm. The 
downbeat that accompanies the upsweep of the armstroke probably contributes 
to the total propulsive force during that phase of the stroke, while also 
preventing the hips from being pulled down by the upward motion of the arm. 
Of course, the lateral components of first and third leg beats also assist 
body roll and, thus, maintenance of lateral alignment.
Straight Two-Beat Kick
There are two forms of the two-beat rhythm in use today: the straight 
two-beat kick, which will be described in this section, and the two-beat 
crossover kick discussed in the next. The timing for the straight two-beat 
kick is shown in figure 4.17. The swimmer executes two downbeats with his 
legs during each complete stroke cycle, or one downbeat per armstroke. Each 
downbeat of a particular leg takes place during both the insweep and upsweep 
of the corresponding armstroke. That is, the right leg kicks down during the 
right armstroke and vice versa (see figure 4.17, b and c for the right 
armstroke and figure 4.17, e and f for the left).
Of course, the other leg will be kicking up at the same time the downbeat of 
the opposite leg is taking place. The legs then hang in an open, or 
separated, position while the arm is recovered over the water and while it 
is sweeping down to the catch position. Thus, there is no help from the kick 
during this deceleration period of the armstroke.
The two-beat kick requires less energy than other rhythms, which may explain 
why it is preferred by many distance swimmers. Female swimmers, in 
particular, seem to gravitate toward this rhythm. This may be because they 
are generally more buoyant
than their male counterparts and do not require a vigorous kicking rhythm to 
maintain their bodies in good lateral and horizontal alignment.
Swimmers who use a two-beat kick tend to modify the timing of the arms to 
compensate for the fact that they are not kicking during the downsweeps of 
the right and left arms. The first modification is a change in the stretch 
phase. Two-beat kickers tend to enter one arm later than the other and they 
shorten the downsweep to make a quick catch. Perhaps this is because with no 
kick to reduce their rate of deceleration, they need to reduce the time they 
spend in the downsweep. The second modification many two-beat swimmers make 
is to shorten the insweep of the armstroke. They probably do this because 
there is no kick from the opposite leg to counterbalance the insweep.
Two-Beat Crossover Kick
The two-beat crossover rhythm, illustrated in figure 4.18, is preferred by a 
significant number of male middle distance and distance swimmers. Referring 
to it as a two-beat crossover kick is really a misnomer because there are 
actually four leg beats per stroke cycle: two major downbeats and two minor 
crossover beats. The major downbeats take place during the insweep and 
upsweep of the corresponding armstroke in the identical sequence described 
for the two-beat kick. The partial crossover beats take place during the 
downsweep of each arm, as shown in figure 4.18, a and d.
The crossover beats are performed in the following manner. The legs do not 
hang during the downsweep of the armstroke, as they did in the straight 
two-beat rhythm. Instead, the bottom leg kicks up and in and the top leg 
kicks down and over, causing them to cross midway through their respective 
beats. Swimmers complete the end of second kick downsweep of the armstroke 
while the legs are crossing, then they uncross them in time to execute a 
major downbeat with the leg on the side of the stroking arm during its 
insweep and upsweep.
The leg that crosses over the other will always be the one on the same side 
as the stroking arm. In figure 4.18a, it is the right leg that crosses over 
the left while the right arm sweeps downward. The left leg crosses over the 
right during the downsweep of the left arm in figure 4.18d.
This rhythm appears to be a compromise between the energy-saving two-beat 
kick and the propulsive six-beat kick. Some swimmers, particularly 
less-buoyant males, have probably found intuitively that the two-beat kick 
is not vigorous enough to maintain their bodies in good horizontal and 
lateral alignment, while a six-beat rhythm may require more energy than they 
can sustain for the race distance. Consequently, they have gravitated toward 
the two-beat crossover kick, in which two small crossover beats maintain 
alignment and two large beats aid in propulsion. The two-beat crossover 
rhythm is also popular among swimmers who use wide lateral arm recoveries. 
Crossing the legs probably prevents the hips from being pulled in the 
direction of the sideward-swinging arm.
Straight Four-Beat Kick
There are also two four-beat kicking rhythms in use among competitive 
swimmers, a straight four-beat kick and a four-beat crossover kick. The 
illustrations in figure 4.19 show a swimmer using a straight four-beat kick. 
This rhythm is really a combination of the six-beat and two-beat styles 
described earlier. The swimmer uses a two-beat rhythm during one armstroke 
and a six-beat rhythm during the other armstroke.
Notice that in figures 4.19, a through c, the swimmer executes only one 
downbeat with his right leg during his right armstroke. That downbeat takes 
place during the insweep and upsweep of that armstroke, just as it would 
with a two-beat rhythm. The swimmer kicks downward three times during the 
left armstroke, with each downbeat accompanying a sweep of the arms in the 
same sequence described for the six-beat kick.
The four-beat kick is, apparently, a compromise between the need to save 
energy by reducing the number of kicks per cycle, while at the same time 
mamtaining horizontal alignment and, perhaps, gaining more propulsion than 
can be supplied by a two-beat or two-beat crossover rhythm. Most swimmers 
use the two-beat rhythm during the stroke on the breathing side. This may 
keep the kick from interfering with the breathing movements of the 
diaphragm.
Four-Beat Crossover Kick
The four-beat crossover rhythm, illustrated in figure 4.20, is a combination 
of a two-beat crossover rhythm on one side and a six-beat rhythm on the 
other. The crossover beat comes during the downsweep of the arm on the side 
where only one major downbeat occurs (the left side in figure 4.20). The 
legs would normally hang during this phase if a straight four-beat kick were 
used. But swimmers who use the four-beat crossover rhythm cross the legs, 
top over bottom, during the downsweep of the armstroke on that side (figure 
4.20d). Then they uncross the legs in time to kick down during the insweep 
and upsweep of that arm (figure 4.20, e and f). The legs kick down three 
times in a normal six-beat rhythm during the stroke of the other arm (the 
right arm in figure 4.20, a through c).
Most, but not all, four-beat crossover kickers use the two-beat rhythm 
during the armstroke on the nonbreathing side. As mentioned earlier, 
swimmers tend to rotate less to that side, causing them to recover that arm 
with a wider sweep. These swimmers may be using the crossover beat to 
counteract the disruptive effect of that wide recovery on their lateral 
alignment.
Which Kick Rhythm Is Best?
It is tempting to recommend the six-beat rhythm as the best possible timing 
between the arms and legs. The way the leg beats coincide with the 
propulsive sweeps of the arms is reminiscent of a well-oiled piece of 
machinery. Nevertheless, many world-class swimmers have been successful at 
all distances using other rhythms. Therefore, the six-beat kick cannot be 
recommended for everyone.
Perhaps factors such as body build, buoyancy, specific muscular weakness, 
specific joint flexibility, and various physiological capacities make it 
more efficient for some swimmers to use fewer kicks per stroke cycle. In 
this regard, Persyn, DeMaeyer, and Vervaecke (1975) at the Leuven Institute 
in Belgium have reported the following results from a study of 62 
national-level Belgian and Dutch swimmers.
- Two-beat crossover kickers had longer legs.
- Six-beat kickers had larger vital capacities, greater inward rotating 
ability at their hips, larger hands, and greater triceps and shoulder 
extension strength.
- Six-beat kickers were able to kick faster for short distances.
- Six-beat kickers' legs tended to sink more easily.
On the basis of these results, it is possible that swimmers with long legs 
may gravitate toward two-beat or four-beat rhythms because a six-beat kick 
would cause them to swim with a turnover rate that is too slow. Perhaps, 
also, large, strong, flexible swimmers with fast kicks who are also not very 
buoyant may prefer a six-beat rhythm. Swimmers with a larger vital capacity 
may prefer to gain more propulsion from the six-beat kick because they can 
partially offset the added energy cost through greater oxygen consumption. 
Inward rotation of the hips probably makes the kick more effective, which 
would explain why swimmers who are above average in this ability prefer the 
more propulsive six-beat rhythm. By the same token, swimmers with larger 
hands and greater strength in the triceps and shoulders probably tend toward 
longer strokes where the six-beat rhythm fits best. It is easy to understand 
why swimmers with exceptional kicking speed would choose the six-beat 
rhythm: They can gain more propulsive force from their legs. Finally, 
swimmers with marginal buoyancy may require faster leg rhythms to keep their 
legs from sinking. These are all reasons that swimmers might find a 
particular rhythm more suited to their special abilities.
What about swimmers who make the wrong choice? There may be a number of good 
kickers who use two-beat and four-beat rhythms for reasons that have nothing 
to do with their physical characteristics and abilities. They may simply 
gravitate toward an energy-saving two-beat or four-beat rhythm because of 
training demands. The need to save energy during long training sessions may 
unknowingly encourage some swimmers to switch from a six-beat timing to one 
of the less costly rhythms. And, once a two-beat or four-beat pattern 
becomes ingrained, they end up using it in competition as well.
We can only speculate whether these swimmers might have been faster if they 
had stayed with a six-beat rhythm. After all, we have seen that some 
middle-distance and distance swimmers can save energy and still excel with a 
subdued six-beat kick. Controlled research is needed to determine whether 
two- and four-beat rhythms are more efficient for some swimmers or whether 
the six-beat kick is the superior style for all.
---------------------------------------------

Il 26 Set 2006, 15:51, Castel Chariot <matt...@RIMUOVItiscalinet.it> ha
scritto:

errato Castel,
la sua gambata parte quando il braccio in opposizione e' in fase di
allungo-presa.
Il suo e' il modo piu' corretto di interpretare la nuotata a due colpi.
--------------------------------
Inviato via 
http://arianna.libero.it/usenet/

 Il suo e' il modo piu' corretto di interpretare la nuotata a due colpi.
Domani sono in acqua e vedo
-- 
Happiness happens

 Domani sono in acqua e vedo
si vede che hai una gambata eccezionale,come tutti i cristallini...nemmeno
ti rendi conto di quello che fai:-)


esatto, la gambata della manadu va a incrocià ma ha una sensibile
iperestenzione della caviglia e una gambata delle sue valgono due
gambate normali!!!
Dice che le serve anche per mantere la stessa frequenza di bracciata
per tutta la gara. In sostanza è un leggero propulsore ma forte
coordinatore.

 Kick, magari quel che segue può aiutare a identificare la cosa.
Finalmente ho avuto il tempo e la voglia di leggerlo.
A quanto c'è scritto, quindi la Manaudou userebbe il Two-Beat Crossover 
Kick, che in verità sarebbe un 4 colpi.
Io uso il Six-Beat Kick in gara e per la velocità e il Straight Two-Beat 
Kick per la maggior parte dell'allenamento, a quanto pare.
Anche se probabilmente faccio anche degli usi intermedi tra queste due 
modalità..solo che da solo è difficile capirlo!
-- 
Happiness happens