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The aim of this study was to analyze the agreement of the active drag coefficient measured through drag and propulsion methods. The sample was composed of 18 swimmers (nine boys: 15.9 ± 0.9 years; nine girls: 15.3 ± 1.2 years) recruited from a national swimming team. The velocity perturbation method was used as the drag measurement system and the Aquanex system as the propulsion system. For both sexes combined, the frontal surface area was 0.1128 ± 0.016 m², swim velocity 1.54 ± 0.13 m⋅s-1, active drag 62.81 ± 11.37 N, propulsion 68.81 ± 12.41 N. The level of the active drag coefficient agreement was calculated based on the mean values comparison, simple linear regression, and Bland Altman plots. The mean data comparison revealed non-significant differences (p > 0.05) between methods to measure the active drag coefficient. Both the linear regression (R² = 0.82, p < 0.001) and Bland Altman plots revealed a very high agreement. The active drag coefficient should be the main outcome used in the interpretation of the swimmers' hydrodynamic profile, because it is less sensitive to swimming velocity. Coaches and researchers should be aware that the active drag coefficient can also be calculated based on propulsion methods and not just based on drag methods. Thus, the swimming community can now use different equipment to measure the hydrodynamics of their swimmers. [ABSTRACT FROM AUTHOR]

Our aim was to analyze physiological, kinematical and performance changes induced by swimming training in regional age‐group athletes. Subjects (15.7 ± 2.2 years old) performed a 4 x 50‐m front‐crawl test at maximal velocity (10 s rest interval) in weeks 2, 4, 9 and 12 of a 15‐week macrocycle. Descriptive statistics were used and the percentage of change and smallest worthwhile change (moderate, 0.6‐1.2, and large, > 1.2) were measured. Lactate concentration in the third, seventh and twelfth minute of recovery decreased significantly between weeks 2‐9 (14.1, 15.7 and 17.6%) and increased between weeks 9‐12 (18.2, 18.6 and 19.8%), with the HR presenting only trivial variations during the training period. Stroke length showed a large decrease in the first 50‐m trial between weeks 4‐9 (6.2%) and a large increase between weeks 9‐12 (3.1%). The stroke rate (in all 50‐m trials) increased significantly between weeks 4‐9 (3‐ 7%) and the stroke index had a moderate to large increase in the first and third 50‐m trial (3.6 and 7.1%, respectively) between weeks 9‐12. The overall time decreased by 1.1% between weeks 2‐12, being more evident after week 4. We concluded that physiological, kinematical and performance variables were affected by the period of training in regional age‐group swimmers. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the responses of creatine kinase (CK) and lactate dehydrogenase (LDH) after performing different resistance and aerobic exercise protocols. Twelve recreationally trained men (age, 23.2 ± 5.6 years; body mass, 84.3 ± 9.3 kg; body height, 178.9 ± 4.5 cm; and BMI, 26.3 ± 2.3 kg·m2) volunteered to participate in this study. All subjects were randomly assigned to four experimental protocols (crossover): (a) aerobic training at 60% of VO2max, (b) aerobic training at 80% of VO2max, (c) a resistance exercise (RE) session with a bi-set protocol, and (d) an RE session with a multiple sets protocol. Blood samples were collected before, immediately after and 24 hours following the experimental protocols. After 24 hours, there was a significant increase in CK for the 80% of VO2max protocol vs. the bi-set RE session (p = 0.016). Immediately after the protocols, we observed a significant increase in LDH among certain groups compared to others, as follows: multiple sets RE session vs. 60% of VO2max, bi-set RE session vs. 60% of VO2max, multiple sets RE session vs. 80% of VO2max, and bi-set RE session vs. 80% of VO2max (p = 0.008, p = 0.013; p = 0.002, p = 0.004, respectively). In conclusion, aerobic exercise performed at 80% of VO2max appears to elevate plasma CK levels more than bi-set RE sessions. However, the bi-set and multiple sets RE sessions appeared to trigger greater levels of blood LDH compared to aerobic protocols performed at 60% and 80% of VO2max. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the values of oxygen uptake (VO2) during and after strength training exercises (STe) and ergometer exercises (Ee), matched for intensity and exercise time. Eight men (24 ± 2.33 years) performed upper and lower body cycling Ee at the individual's ventilatory threshold (VE/VCO2). The STe session included half squats and the bench press which were performed with a load at the individual blood lactate concentration of 4 mmol/l. Both sessions lasted 30 minutes, alternating 50 seconds of effort with a 10 second transition time between upper and lower body work. The averaged overall VO2 between sessions was significantly higher for Ee (24.96 ± 3.6 ml·kg·min-1) compared to STe (21.66 ± 1.77 ml·kg·min-1) (p = 0.035), but this difference was only seen for the first 20 minutes of exercise. Absolute VO2 values between sessions did not reveal differences. There were more statistically greater values in Ee compared to STe, regarding VO2 of lower limbs (25.44 ± 3.84 ml·kg·min-1 versus 21.83 ± 2·24 ml·kg·min-1; p = 0.038) and upper limbs (24.49 ± 3.84 ml·kg·min-1 versus 21.54 ± 1.77 ml·kg·min-1; p = 0.047). There were further significant differences regarding the moment effect (p<0.0001) of both STe and Ee sessions. With respect to the moment × session effect, only VO2 5 minutes into recovery showed significant differences (p = 0.017). In conclusion, although significant increases in VO2 were seen following Ee compared to STe, it appears that the load/intensity, and not the material/equipment used for the execution of an exercise, are variables that best influence oxygen uptake. [ABSTRACT FROM AUTHOR]

The present work proposed to study the oxygen uptake slow component (VO2 SC) of breaststroke swimmers at four different intensities of submaximal exercise, via mathematical modeling of a multi-exponential function. The slow component (SC) was also assessed with two different fixed interval methods and the three methods were compared. Twelve male swimmers performed a test comprising four submaximal 300 m bouts at different intensities where all expired gases were collected breath by breath. Multi-exponential modeling showed values above 450 ml·min−1 of the SC in the two last bouts of exercise (those with intensities above the lactate threshold). A significant effect of the method that was used to calculate the VO2 SC was revealed. Higher mean values were observed when using mathematical modeling compared with the fixed interval 3rd min method (F=7.111; p=0.012; η2=0.587); furthermore, differences were detected among the two fixed interval methods. No significant relationship was found between the SC determined by any method and the blood lactate measured at each of the four exercise intensities. In addition, no significant association between the SC and peak oxygen uptake was found. It was concluded that in trained breaststroke swimmers, the presence of the VO2 SC may be observed at intensities above that corresponding to the 3.5 mM-1 threshold. Moreover, mathematical modeling of the oxygen uptake on-kinetics tended to show a higher slow component as compared to fixed interval methods. [ABSTRACT FROM AUTHOR]

The present work proposed to study the oxygen uptake slow component (VO2 SC) of breaststroke swimmers at four different intensities of submaximal exercise, via mathematical modeling of a multi-exponential function. The slow component (SC) was also assessed with two different fixed interval methods and the three methods were compared. Twelve male swimmers performed a test comprising four submaximal 300 m bouts at different intensities where all expired gases were collected breath by breath. Multi-exponential modeling showed values above 450 ml·min−1 of the SC in the two last bouts of exercise (those with intensities above the lactate threshold). A significant effect of the method that was used to calculate the VO2 SC was revealed. Higher mean values were observed when using mathematical modeling compared with the fixed interval 3rd min method (F=7.111; p=0.012; η2=0.587); furthermore, differences were detected among the two fixed interval methods. No significant relationship was found between the SC determined by any method and the blood lactate measured at each of the four exercise intensities. In addition, no significant association between the SC and peak oxygen uptake was found. It was concluded that in trained breaststroke swimmers, the presence of the VO2 SC may be observed at intensities above that corresponding to the 3.5 mM-1 threshold. Moreover, mathematical modeling of the oxygen uptake on-kinetics tended to show a higher slow component as compared to fixed interval methods. [ABSTRACT FROM AUTHOR]

The objective of this study was to analyze the effect of supplementation with creatine and glutamine on physical fitness of military police officers. Therefore, an experimental double blind study was developed, with the final sample composed by 32 men randomly distributed into three groups: a group supplemented with creatine (n=10), glutamine (n=10) and a placebo group (n=12) and evaluated in three distinct moments, in an interval of three months (T1, T2 and T3). The physical training had a weekly frequency of 5 sessions x 90 min, including strength exercises, local muscular resistance, flexibility and both aerobic and anaerobic capacity. After analyzing the effect of time, group and interaction (group x time) for measures that indicated the physical capabilities of the subjects, a significant effect of time for the entire variable was identified (p<0,05). However, these differences were not observed when the univaried intragroups and intergroups analysis was performed (p>0,05). In face of the results it was concluded that supplementation with creatine and glutamine showed no ergogenic effect on physical performance in military police officers. [ABSTRACT FROM AUTHOR]

Aging produces several respiratory limitations and reduces tolerance to physical efforts, sometimes leading to pulmonary diseases in the elderly. The literature draws attention to the possible benefits of Yoga practice among the elderly, presenting evidence for significant improvements in quality of life. It was hypothesized that yoga practice can improve respiratory function in the elderly. The effects of a yoga program on pulmonary volumes and respiratory muscle strength were verified in 36 elderly women divided into a yoga group [YG] (63.1 ± 13.3 years of age) and a control group (61.0 ± 6.9 years of age). Maximal inspiratory and expiratory pressure (MIP and MEP) were assessed by a manovacuometer and tidal volume (VT), vital capacity (VC) and minute ventilation (VE) were measured by a ventilometer. The program comprised 65 min sessions, 3 times/week during 12 weeks. The heart rate and respiratory rate decreased significantly in the YG (76-39 ± 8-03 vs. 74-61±10.26 bpm and 18.61 ± 3.15 vs. 16.72 ± 3.12 resp/min, respectively). In the YG, VT and VE increased significantly (0.55 ± 0.22 vs. 0.64 ± 0.2 ml and 9.19 ± 2.39 vs. 10.05 ± 2.11 ml, respectively), as well as VC (1.48 ± 0.45 vs. 2.03 ± 0.72 ml). Improvements were also found in MIP and MEP in the YG (62.17 ± 14.77 vs. 73.06 ± 20.16 cmH2O and 80.56 ± 23.94 vs. 86.39 ± 20.16 cmH2O, respectively). It was concluded that a 12-week yoga program significantly improves pulmonary function of aged women. [ABSTRACT FROM AUTHOR]

Complex training (CXT) is the result of a combination of strength and plyometric exercises in the same session. This method has recently been used in the preparation of athletes of different sports. The aim of the present study was to observe the acute effects of a CXT program of 6 weeks: i) on agility with the ball, sprinting and the efficiency of crossing and shooting in youth soccer players; ii) and the influence of the number of CXT sessions per week (one vs. two). Sixteen youth male soccer players were randomly divided into three groups: a group that performed one weekly CXT session (GCT1, n = 5, age: 13.80 ± 0.45 years); or a group that performed two weekly CXT sessions (GCT2, n = 5, age: 14.20 ± 0.45 years); or a control group that did not perform the CTX (n = 6, age: 14.20 ± 0.84 years). All groups maintained their regular soccer training sessions. No significant interactions were found between GCT1 and GCT2 in all variables. Significant statistical differences were identified (F = 1139, p = 0.02, μp2 = 0531) in the pre-test versus post-test, for both experimental groups, in shot effectiveness. In conclusion, the CXT program proved to be an effective method in boosting abilities and motor skills associated with soccer among young athletes, particularly in increasing shot effectiveness. [ABSTRACT FROM AUTHOR]

This study aimed to analyze the acute effects of a single session of a community-based group exercise program combining step aerobics and bodyweight resistance exercise on blood pressure in healthy young adult women. Twenty-three healthy young adult women (aged 31.57 ± 7.87 years) participated in two experimental sessions (exercise and control) in a crossover study design. Blood pressure was monitored before, immediately after and at 10, 20 and 30 min of recovery. The exercise session consisted of four phases: 1) a warm-up (5 min of dance aerobics); 2) aerobic exercise training (30 min of step aerobics); 3) resistance exercise training (six sets of 12 repetitions of three bodyweight exercises in a circuit mode, 10 min); and 4) a cool-down (5 min of breathing and flexibility exercises); totaling 50 min of duration. Systolic blood pressure after exercise was significantly lower compared to control at the 10th min (-10.83 ± 2.13 vs. -2.6 ± 2.13 mmHg; p = 0.009), 20th min (-11.26 ± 2.13 vs. -3.04 ± 2.13 mmHg; p = 0.009) and 30th min of recovery (-10.87 ± 2.39 vs. -0.48 ± 2.39 mmHg; p = 0.004). A single session of a community-based group exercise program combining step aerobics and bodyweight resistance exercise was effective in inducing significant post-exercise hypotension in healthy young adult women. This type of low-cost exercise interventions may have an important role in the prevention of cardiovascular diseases and in community health promotion. [ABSTRACT FROM AUTHOR]

The current study aimed to compare the effects of two exercise programs (Strength Training and Hydro Gymnastics) on the functional and cardiorespiratory abilities of Portuguese postmenopausal women. The study population consisted of 38 volunteers (age: 66.9 ± 6.1 years, body mass: 73.70 ± 10.38 kg, and body height: 1.55 ± 0.10 m). Subjects were randomly divided into two experimental groups and one control group: one group performed 24 weeks of strength training (GST; n = 14), another performed 24 weeks of hydro gymnastics (GH; n = 17) and a control group (CG; n = 7), where the subjects continued with their regular daily activities without involvement in any physical exercise program. Three assessments were performed: before the beginning of the program, 12 weeks after the start of the training program and 24 weeks after the start of the program. To assess the functional ability of the participants, several tests proposed by Jones and Rikli (2002) were performed. To evaluate the cardiorespiratory ability of the participants, a modified treadmill Bruce test was applied. Significant differences (p<0.05) were found between the two training methods in the tests, which primarily demanded muscular strength. Body mass and the body mass index showed significant differences during the three stages of assessment in the GST group (p<0.05). With respect to the values that represent the variables of cardiorespiratory ability, positive and significant changes were observed in the two experimental groups. It was concluded that both exercise programs promoted improvements in some indicators of the functional and cardiorespiratory abilities of Portuguese postmenopausal women. [ABSTRACT FROM AUTHOR]

Few functional agility tests for water polo take into consideration its specific characteristics. The preliminary objective of this study was to evaluate the reliability of an agility test for water polo players. Fifteen players (16.3 ± 1.8 years old) with a minimum of two years of competitive experience were evaluated. A Functional Test for Agility Performance (FTAP) was designed to represent the context of this sport. Several trials were performed to familiarize the athlete with the movement. Two experienced coaches measured three repetitions of the FTAP. Descriptive statistics, repeated measures analysis of variance (ANOVA), 95% limit of agreement (LOA), intraclass correlation coefficient (ICC) and standard error of measurements (SEM) were used for data analysis. It was considered that certain criteria of reliability measures were met. There was no significant difference between the repetitions, which may be explained by an effect of the evaluator, the ability of the players or fatigue (p > 0.05). The ICC average from evaluators was high (0.88). The SEM varied between 0.13 s and 0.49 s. The CV average considering each individual was near 6-7%. These values depended on the condition of measurement. As the FTAP contains some characteristics that create a degree of unpredictability, the same athlete may reach different performance results, increasing variability. An adjustment in the sample, familiarization and careful selection of subjects help to improve this situation and enhance the reliability of the indicators. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The main aim of the present study was to analyze the relationships between dry land strength and power measurements with swimming performance. Ten male national level swimmers (age: 14.9 ± 0.74 years, body mass: 60.0 ± 6.26 kg, height: 171.9 ± 6.26, 100 m long course front crawl performance: 59.9 ± 1.87 s) volunteered as subjects. Height and Work were estimated for CMJ. Mean power in the propulsive phase was assessed for squat, bench press (concentric phase) and lat pull down back. Mean force production was evaluated through 30 s maximal effort tethered swimming in front crawl using whole body, arms only and legs only. Swimming velocity was calculated from a maximal bout of 50 m front crawl. Height of CMJ did not correlate with any of the studied variables. There were positive and moderate-strong associations between the work during CMJ and mean propulsive power in squat with tethered forces during whole body and legs only swimming. Mean propulsive power of bench press and lat pull down presented positive and moderate-strong relationships with mean force production in whole body and arms only. Swimming performance is related with mean power of lat pull down back. So, lat pull down back is the most related dry land test with swimming performance; bench press with force production in water arms only; and work during CMJ with tethered forces legs only. [ABSTRACT FROM AUTHOR]