Breaststroke performance, selected physiological variables and stroke rate

The purpose of this study was to determine whether selected physiological variables and stroke rate are associated with and able to detect changes in breaststroke performance. Fifteen nationally ranked breaststroke swimmers undertook a 5x200m incremental swimming step test followed by a national competition 7-10 days later (phase 1). Eleven of the subjects repeated the same procedure 12 months later (phase 2). From the step test, plots of data against swimming speed identified the swimming speed eliciting a blood lactate concentration of 2mmol.l^-1 (s-2mM), 4mmol.1^-1 (s-4mM), 6mmol.1^-1 (s-6mM) and the speed at maximum heart rate (s-MHR). The stroke rate (SR) and RPE at 1.3m.s^-1 (SR1.3m.s^-1, RPE1.3m.s^-1) were also calculated from this data. Significant moderate relationships were found between blood lactate variables and 100m and 200m competition finishing times (100m FT and 200m FT) in both phase 1 and phase 2 of the study (r=-0.60-0.82). An increase in the 100m FT (p<0.002) and the 200m FT (p<0.001) between phase 1 and phase 2 of the study coincided with a reduction in s-2mM (p<0.003) and s-6mM (p<0.022) and an increase in SR1.3m.s^-1 (p<0.008) and the sum of 4 skinfolds (p<0.024). The s-2mM, s-4mM and s-6mM demonstrated significant reproducible relationships with 100m and 200m finishing times. Changes in s-2mM and s-6mM coincided with changes in competition performance suggesting that a loss of endurance fitness affected performance.