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Biomechanics and Medicine in Swimming XI

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<strong>Biomechanics</strong><strong>and</strong>medic<strong>in</strong>e<strong>in</strong>swimm<strong>in</strong>gXi<br />

were collected, however because of miss<strong>in</strong>g data the f<strong>in</strong>al analysis <strong>in</strong>cluded<br />

149 f<strong>in</strong>als races swam by 98 swimmers. The age of the swimmers<br />

ranged between 14 <strong>and</strong> 29 years. Race results were collected from the<br />

host organiz<strong>in</strong>g committee <strong>and</strong> used to determ<strong>in</strong>e FINA po<strong>in</strong>ts.<br />

Blood samples were collected with<strong>in</strong> three to five m<strong>in</strong>utes after complet<strong>in</strong>g<br />

the race. Samples were obta<strong>in</strong>ed from f<strong>in</strong>ger stick <strong>and</strong> analyzed<br />

with a Lactate ProTM (Arkray Lt., Japan). Swimmers then proceeded<br />

to the recovery pool <strong>and</strong> performed their own coach-directed active recovery.<br />

[BLa] was repeatedly assessed until it was below 2 mmol•L-1.<br />

The distance of each active recovery segment as well as the total active<br />

recovery distance <strong>and</strong> the change <strong>in</strong> [BLa] from post-race to the lowest<br />

concentration achieved follow<strong>in</strong>g the active recovery were recorded.<br />

Several swimmers competed <strong>in</strong> more than one f<strong>in</strong>al race <strong>and</strong> had<br />

data from multiple races <strong>in</strong>cluded <strong>in</strong> the analysis, therefore the assumption<br />

of <strong>in</strong>dependence was violated. To evaluate the relationship between<br />

post-race [BLa] <strong>and</strong> swimmers characteristics (age <strong>and</strong> sex) <strong>and</strong> the races<br />

(stroke <strong>and</strong> distance) the Generalized Estimat<strong>in</strong>g Equations (GEE)<br />

technique was used (Hard<strong>in</strong> & Hilbe, 2002), which accommodates for<br />

a violation of the <strong>in</strong>dependence assumption. To evaluate active recovery<br />

distance on [BLa] disappearance an exploratory model build<strong>in</strong>g approach<br />

was used with [BLa] follow<strong>in</strong>g active recovery as the dependent<br />

variable, while sex was entered <strong>in</strong> the model as a two-level factor. Age,<br />

post-race [BLa], <strong>and</strong> active recovery distance were entered as covariates.<br />

The maximal model was developed, then non-significant effects were<br />

removed until the most parsimonious model was achieved. Each model<br />

was compared with the previous us<strong>in</strong>g Quasi Likelihood under Independence<br />

Model Criterion (QIC) <strong>in</strong>dex to determ<strong>in</strong>e whether removal<br />

of non-significant parameters improved the fit of the model. Values are<br />

expressed as mean ± SD <strong>and</strong> statistical significance was set at p

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