Repository logo

Browsing by Author "Costa, Mário J."

Now showing 1 - 2 of 2
  • Effect of Gender, Energetics, and Biomechanics on Swimming Masters Performance
    Publication . Ferreira, Maria I.; Barbosa, Tiago M.; Neiva, Henrique; Marta, Carlos C.; Costa, Mário J.; Marinho, Daniel
    The purpose of this study was to analyze the effect of gender and energetics on biomechanics and performance of masters swimmers over 1 season. Twenty-five masters swimmers (14 male and 11 female) were assessed 3 times (TP1, TP2, and TP3) during a season (male personal record in 200-m freestyle event: 173.00 ± 31.41 seconds: female personal record in 200-m freestyle event: 200.73 ± 25.02 seconds). An incremental 5 × 200-m step test was selected to evaluate velocity at 4 mmol·l⁻¹ of blood lactate concentration (v4), maximal blood lactate concentration after exercise (La(peak)), maximal oxygen uptake (V̇O2max), stroke frequency, stroke length (SL), stroke index (SI), and propelling efficiency of the arm stroke (η(p)). The 200-m freestyle performance and average swimming velocity (v200) were also monitored. Significant differences were observed between males and females for the 200-m freestyle performance, SL, SI, and La(peak). Performance (205.18 ± 24.47 seconds; 197.45 ± 20.97 seconds; 193.45 ± 18.12 seconds), SL (1.69 ± 0.17 m; 1.79 ± 0.13 m; 1.78 ± 0.15 m), SI (1.68 ± 0.31 m²·c⁻¹·s⁻¹; 1.83 ± 0.27 m²·c⁻¹·s⁻¹; 1.85 ± 0.27 m²·c⁻¹·s⁻¹), η(p) (0.32 ± 0.04; 0.33 ± 0.03; 0.33 ± 0.04), and V̇O2max (38.71 ± 3.44 ml·kg⁻¹·min⁻¹; 43.43 ± 3.71 ml·kg⁻¹·min⁻¹; 43.95 ± 7.02 ml·kg⁻¹·min⁻¹) have changed significantly throughout the season (TP1, TP2, and TP3, respectively) in female swimmers. In male, significant changes were found in η(p) (0.33 ± 0.07; 0.36 ± 0.05; 0.36 ± 0.06) and V̇O2max (41.65 ± 7.30 ml·kg⁻¹·min⁻¹; 45.19 ± 6.55 ml·kg⁻¹·min⁻¹; 50.19 ± 9.65 ml·kg⁻¹·min⁻¹) over the season (TP1, TP2, and TP3, respectively). Gender presented a significant effect on SL (TP2: η(p)² = 0.29; TP3: η(p)² = 0.37), SI (TP2: η(p)² = 0.25), and La(peak) (TP3: η(p)² = 0.42). v4 (TP1: η(p)² = 0.23), SL (TP1: η(p)² = 0.46), SI (TP1: η(p)² = 0.78; TP2: η(p)² = 0.37; TP3: η(p)² = 0.32), and η(p) (TP1: η(p)² = 0.28) had a significant effect on performance. Male masters swimmers have better performance, SL, SI, and La(peak) than female counterparts. Female masters swimmers enhanced significantly the 200-m freestyle performance over the season due to the improvement in swimming technique (SL, SI, and η(p)) and energetic factors (v4 and V̇O2max). Nonsignificant improvements were observed for the males' performance. Gender has a significant effect on SL, SI, and La(peak). Therefore, performance is more dependent on technical factors than energetics.
    2015Journal article Open access Show more
  • Effects of a swimming program on infants' heart rate response
    Publication . Costa, Mário J.; Barbosa, Tiago M.; Ramos, Alberto Manuel Sousa; Marinho, Daniel
    The physiological response has been used to characterize or estimate physical demands while exercising. The aim of this study was to analyze the infant's physiological adaptations over an intervention water program. Fourteen infants (36±5.08 months old) were tested before (M1) and 4 months after (M2) a well-designed swimming program aiming to develop aquatic readiness, cognitive behavior and social interaction. The physiological response was assessed based on heart rate measurements (HR, bpm) at a sampling rate of 1 Hz during several basic aquatic motor skills: 1) individual displacement in ventral position (HR@InD); 2) Individual displacement in vertical position (HR@VD); 3) immersion (HR@Im); 4) voluntary underwater displacement (HR@UnD); 5) jump from the deck (HR@JD); 6) jump from the swimming mat (HR@JM); 7) from a swimming slider (HR@Sli). The HR@Im showed the lowest values (~119 bpm) at the end of the program. Main trend was for a HR decreased over time (HR@Im: -14.17±17.76%; HR@InD: -8.16±9.16%; HR@JD: -10.36±12.70%; HR@Sli: -3.48±6.40%. In all other skills, HR remained unchanged. Our findings suggest that infants experience significant hear rate adaptations while participating on a swimming program. The HR decreases suggests a higher capability to perform the basic aquatic motor skills and a less stressful behavior through the lessons.
    2016-04Journal article Open access Show more