Biomechanics and Medicine in Swimming XI

BiomechanicsandmedicineinswimmingXi
Figure 1. The set up utilized for measuring the subject’s hydrostatic
weight. In this case the subject is wearing a “standard” swimming suit.
The second test was carried out in the laboratory: chest circumferences
were measured at maximal inspiration and maximal expiration when
the subjects were wearing the S or Xg suits. Lung volumes (VC: Vital
Capacity, ERV: Expiratory Reserve Volume, VT: Tidal Volume, IRV:
Inspiratory Reserve Volume) in the two conditions were measured
(Standard Lung Function Test) by means of a portable spirometer (K4
Cosmed, Italy). These tests were carried out according to standard technical
procedures (Guidelines for lung function test 1994). The subjects
were first familiarized with the procedures; they were asked to repeat
these measurements four times, the average value of these measures was
utilized for further analysis.
With regard to the statistical analysis, mean and standard deviation
(SD) were calculated for all the variables. Test-retest intra-class correlation
coefficient (ICC) was calculated to assess the reliability of the
hydrostatic lift. Non/parametric Wilcoxon test was used to compare differences
of hydrostatic lift values in the two conditions of suit. The 95%
level of significance was accepted for all comparisons (p