Mário J. Costa, Lúcia Cruz, Ana Simão and Tiago M. Barbosa
The aim of this study was to compare the cardiovascular and perceived effort of head‐out water exercises selecting different limb strategies and using resistance equipment. Ten young women were randomly assigned to perform at 132 bpm during five minutes different head‐out aquatic exercises: (i) horizontal arms abduction (Ab); (ii) horizontal arms abduction with dumbbells (AbD); (iii) frontal kick (Fk); (iv) frontal kick with leggings (FkLeg), and; (v) aquatic skiing (Ski). Cardiovascular effort was measured by monitoring the heart rate, blood pressure and double product. Perceived effort was assessed by the Borg’s scale. Within‐routines comparison was computed using repeated‐ measures ANOVA followed‐up by the Bonferroni post‐hoc test. Considering the percentage of the maximal heart rate, participants reached 72.88 ± 12.90% in the FkLeg, 65.99 ± 10.91% in the Fk, 62.62 ± 7.20% in Ski, 57.27 ± 11.58% in AbD and 57.12 ± 12.09% in Ab. Comparing exercises, higher heart rates were observed in the FkLeg (140.40 bpm) than Ab (110.30 bpm) or AbD (110.00 bpm). Significant differences were found in the systolic blood pressure when compared to the Fk (120.60 mmHg) and Ab (104.50 mmHg). Double product was higher in the FkLeg (16990) showing a meaningful difference when compared to Ab (11608) or AbD (12001). The highest perceived effort was found in the FkLeg (15.80) with meaningful variations compared to Ab (11.70), the Fk (13.70) and Ski (10.40). Thus, different head‐ out water exercises result in different intensities. The actions by lower limbs promote a higher cardiovascular response, whereas the upper limbs actions trigger a lower exertion. Moreover, exercising the four limbs concurrently seems to be less intense than using only two limbs with an aid.
Mário J. Costa, Govindasamy Balasekaran, J. Paulo Vilas-Boas and Tiago M. Barbosa
The purpose of this systematic review was to summarize longitudinal studies on swimming physiology and get implications for daily practice. A computerized search of databases according to the PRISMA statement was employed. Studies were screened for eligibility on inclusion criteria: (i) present two testing points; (ii) on swimming physiology; (iii) using adult elite swimmers; (iv) no case-studies or with small sample sizes. Two independent reviewers used a checklist to assess the methodological quality of the studies. Thirty-four studies selected for analysis were gathered into five main categories: blood composition (n=7), endocrine secretion (n=11), muscle biochemistry (n=7), cardiovascular response (n=8) and the energetic profile (n=14). The mean quality index was 10.58 ± 2.19 points demonstrating an almost perfect agreement between reviewers (K = 0.93). It can be concluded that the mixed findings in the literature are due to the diversity of the experimental designs. Micro variables obtained at the cellular or molecular level are sensitive measures and demonstrate overtraining signs and health symptoms. The improvement of macro variables (i.e. main physiological systems) is limited and may depend on the athletes’ training background and experience.
Jorge E Morais, Nuno D Garrido, Mário C Marques, António J Silva, Daniel A Marinho and Tiago M Barbosa
The aim of this study was to assess the: (i) gender; (ii) performance and; (iii) gender versus performance interactions in young swimmers’ anthropometric, kinematic and energetic variables. One hundred and thirty six young swimmers (62 boys: 12.76 ± 0.72 years old at Tanner stages 1-2 by self-evaluation; and 64 girls: 11.89 ± 0.93 years old at Tanner stages 1-2 by self-evaluation) were evaluated. Performance, anthropometrics, kinematics and energetic variables were selected. There was a non-significant gender effect on performance, body mass, height, arm span, trunk transverse surface area, stroke length, speed fluctuation, swimming velocity, propulsive efficiency, stroke index and critical velocity. A significant gender effect was found for foot surface area, hand surface area and stroke frequency. A significant sports level effect was verified for all variables, except for stroke frequency, speed fluctuation and propulsive efficiency. Overall, swimmers in quartile 1 (the ones with highest sports level) had higher anthropometric dimensions, better stroke mechanics and energetics. These traits decrease consistently throughout following quartiles up to the fourth one (i.e. swimmers with the lowest sports level). There was a non-significant interaction between gender and sports level for all variables. Our main conclusions were as follows: (i) there are non-significant differences in performance, anthropometrics, kinematics and energetics between boys and girls; (ii) swimmers with best performance are taller, have higher surface areas and better stroke mechanics; (iii) there are non-significant interactions between sports level and gender for anthropometrics, kinematics and energetics.