Biomechanics and Medicine in Swimming XI

Fourteen highly trained male swimmers were divided into two groups (E (n = 7;
22.7±2.7 yr.; 81.68 ±12.5 kg; 1.83 ± 0.10m and C (n=7; 18.8 ± 1.4 yr.; 69.1 ± 8.4 kg;
BiomechanicsandmedicineinswimmingXi
1.77 ± 0.04 m) gave written informed consent to participate in the study, which was
granted ethical approval by the Scientific Committee of the Faculty of Human Kinetics
of the Technical University of Lisbon. The Elite group consisted of swimmers who have
represented the Portuguese National Team in International Competition in freestyle
Oxygen Uptake Kinetics and Performance in events (200 meter The subjects or above). were Club familiarised level swimmers with the test were procedures characterized and equip- as having never
Swimming
represented ment their used country in the at experiment the senior and level, were but instructed all of the to subjects avoid strenuous underwent regular
training and exercise competed in the regularly 24 hours in preceding National the Championships.
test.
The subjects Swimmers were familiarised were required with to report the test to the procedures pool on 3 and occasions equipment over a used in the
reis, J.F., Alves, F.B.
experiment 10 and day were period. instructed All the tests to were avoid interspersed strenuous with exercise at least in 24-h the recovery. 24 hours preceding
the test. Subjects underwent a preliminary test comprising 5 x 200 m with 30 s
CIPER, Faculty of Human Kinetics, Lisbon, Portugal
Swimmers rest and were 5-10% required velocity to report increments to the for pool determination on 3 occasions of maximal over a oxy- 10 day period.
All the tests gen were uptake interspersed (VO2 max ) and with ventilatory at least threshold 24-h (VT). recovery. The last Subjects repetition underwent a
The purpose of this study was to compare the VO2 kinetics in two
preliminary
sub-
was test performed comprising at maximal 5 x 200 velocity m with (vVO 30 s 2 rest ). VOand 2 max 5-10% was recorded velocity as the increments for
maximal intensities in elite (E) and club-level (C) swimmers. After pre-
determination highest of maximal 30 s average oxygen and VT uptake was established ( VO2 maxusing
the V-slope method
vious determination of VO2 max and ventilatory threshold (VT), four-
(Beaver al., 1986). On subsequent test days, the swimmers performed
teen swimmers were divided into two groups: E (n = 7; 22.7±2.7 yr) and
two 7-min square-wave transitions from rest to 25%Δ [VT + 0.25 x
C (n=7; 18.8 ± 1.4 yr) and performed two constant velocity swimming
(VO2 max- VT)] (H) and 70%Δ (S) with at 1-h rest in between. The
bouts at Δ25% (Heavy) [= VT + 0.25 x (VO2 max- VT)] and Δ70% (Se-
subjects returned to the pool within one week to repeat the procedure,
vere) for determination of VO2 kinetics. The E group presented a faster
giving a total of two H and two S exercise transitions.
time constant of the primary phase VO2 response than C in severe
Heart Rate was recorded throughout each swimming bout and aver-
swimming (13.3±3.4s and 18.4±4.6s, respectively, p>0.05) which
aged every 5 s. Blood lactate concentration was determined after each
was also correlated with endurance performance, recorded as the
square-wave transition (Lactate Pro (Arkray, Kyoto, Japan). All the tests
time attained in an official 400 freestyle event (r= 0.6, p