The purpose of the present study was to ascertain the influence of reduced pulmonary ventilation ... more The purpose of the present study was to ascertain the influence of reduced pulmonary ventilation on blood acid-base balance during swimming. Five trained swimmers (age 212 years, height 1875 cm and weight 836 kg) volunteered to participate in this study. They had to swim 400 m front crawl at velocity VOBLA two times. Firstly, they were taking breath every two strokes (B2). During the second trial they swam the same distance at the similar velocity, however with reduced breathing frequency, taking breath every four strokes (B4). Measures included lactate concentration ([LA]) and parameters of blood acid-base status (pH, Po2, Pco2) before and during the third minute after the exercise. There was only Pco2 significantly increased after B4 than after B2 (p<0.05). After the exercise other parameters ([LA], pH, HCO3 and Po2) did not change significantly in response to reduced breathing frequency during swimming. It may be concluded that the reduced breathing frequency during front c...
The purpose of the present study was to ascertain the influence of reduced breathing on the blood... more The purpose of the present study was to ascertain the influence of reduced breathing on the blood acid-base status during swimming at 90% velocity of maximal 200-m front crawl. Ten swimmers (age 16.6 ± 1.8 years, height 180 ± 7 cm and weight 70 ± 7 kg) volunteered to participate in this study. They performed maximal 200-m front crawl swim. Then they performed a sub-maximal front crawl swim twice to exhaustion: first, by taking breath every two strokes (B2) and second, by taking breath every four strokes (B4). The swimming velocity was determined as 90% of maximal velocity at 200-m front crawl swim. Measures included lactate concentration ([LA]) and parameters of blood acid-base status (pH, Po2, Pco2, [HCO3-]) before and during the first and the third minute after the exercise. Swimmers swam with B2 significantly longer as they did with B4 (p < 0.05). [LA] was significantly lower after swimming with B4 than after swimming with B2 (p < 0.05). Pco2 and [HCO3-] were significantly ...
The purpose of the study was to establish whether anaerobic lactic production and oxygen uptake c... more The purpose of the study was to establish whether anaerobic lactic production and oxygen uptake could limit the energy supply during 200 m front crawl swimming. Twelve male swimmers performed four swims of 200 m crawl at intensities from 80%, 90%, 100% to 110% (until exhaustion) on separate days with a swimming snorkel. Respiratory parameters (VE, Vo2), blood parameters (pH, [LA-]) and heart rate (HR) were measured. The results demonstrate that limitations in VE, Vo2 and HR during swimming occur during supramaximal swims (no further increase in measured maximal parameters and time-constant parameters) in comparison to maximal swims. We also found limitations in the obtained maximal [LA-] and minimal pH values. It is possible to conclude that individual limitations in VE, Vo2, HR and consequently acidosis could be limiting factors of individual 200 m front crawl performances due to energy supply restrictions.
The aim of the study was to ascertain how four weeks of training with reduced breathing frequency... more The aim of the study was to ascertain how four weeks of training with reduced breathing frequency during front crawl swimming would influence a maximal 200 meters front crawl performance. Two matched groups of five recreational-level swimmers trained 5 times per week. During each swimming session breathing frequency was distinguished between the control (the B2 group was taking a breath every second stroke cycle) and an experimental (the B4 group was taking a breath every fourth stroke cycle). The swimmers performed a maximal 200 meters front crawl swim with an optional breathing pattern before and after the training. Both groups swam the maximal 200 meters front crawl after the training significantly faster then before the training. This improvement was significantly greater in the B4 group than the B2 group. B4 group swam the maximal 200 meters front crawl after the training with fewer breaths than before the training. The breathing pattern in the B2 group was unchanged by the tra...
The purpose of the present study was to ascertain whether the backward extrapolation method can b... more The purpose of the present study was to ascertain whether the backward extrapolation method can be used to calculate the pulmonary ventilation (VE) appropriate in two different breathing conditions during swimming: with and without reduced breathing frequency. Five trained swimmers swam 400 m front crawl at Onset of Blood Lactate Accumulation (OBLA) velocity taking a breath every stroke cycle (normal breathing - NB). Then they repeated 400-m front crawl at NB velocity and with NB stroke frequency taking a breath every second stroke cycle (restricted breathing - RB). The measures included the parameters of blood acid-base status (pH, Po2, Pco2, [HCO3-]) and pulmonary ventilation (VE). Pulmonary ventilation during swimming was obtained by the backward extrapolation method (VEe) and by a theoretical model (VEt). There was no significant difference between VEeand VEtin NB. But the paired t-test showed a significant (p<0,05) difference between these two parameters in RB. Pco2 was also...
We aimed to identify potential physiological and performance differences of trained cross-country... more We aimed to identify potential physiological and performance differences of trained cross-country skiers (V˙o2max=60±4 ml ∙ kg–1 ∙ min–1) following two, 3-week long altitude modalities: 1) training at moderate altitudes (600–1700 m) and living at 1500 m (LMTM;N=8); and 2) training at moderate altitudes (600–1700 m) and living at 1500 m with additional nocturnal normobaric hypoxic exposures (FiO2 =0.17;LHTM; N=8). All participants conducted the same training throughout the altitude training phase and underwent maximal roller ski trials and submaximal cyclo-ergometery before, during and one week after the training camps. No exercise performance or hematological differences were observed between the two modalities. The average roller ski velocities were increased one week after the training camps following both LMTM (p=0.03) and LHTM (p=0.04) with no difference between the two (p=0.68). During the submaximal test, LMTM increased the Tissue Oxygenation Index (11.5±6.5 to 1.0±8.5%; p=0.0...
In front crawl swimming at maximum exertion and in swimming at maximum exertion with different fo... more In front crawl swimming at maximum exertion and in swimming at maximum exertion with different forms of artificially created additional resistance, certain kinematic and dynamic parameters can be measured and the active drag, assuming that there is an equal power output in all cases can be estimated. Seventeen highly trained male swimmers, all over 16 years of age and specialized in front crawl swimming participated in this study. The pretraining mean (SE), of the height and the body mass of the subjects were 180.6+4.7 cm, and 74.3, +7 kg. The mean active drag at maximal swimming velocities ranged from 64.94 N to 76.37 N in front crawl swimming. It was found out that the forces of the active drag, calculated from the measured kinematic and dynamic parameters in front crawl sprints at maximum exertion and front crawl swimming at maximum exertion with different forms of artificially created additional resistance, were not significantly statistically different. It was concluded that th...
This study aimed to examine the correlation of different dry land strength and power tests with s... more This study aimed to examine the correlation of different dry land strength and power tests with swimming start performance. Twenty international level female swimmers (age 15.3 ± 1.6 years, FINA point score 709.6 ± 71.1) performed the track freestyle start. Additionally, dry land tests were conducted: a) squat (SJ) and countermovement jumps (CMJ), b) squat jumps with additional resistance equivalent to 25, 50, 75 and 100% of swimmers’ body weight [BW]), and c) leg extension and leg flexion maximal voluntary isometric contractions. Correlations between dry land tests and start times at 5, 10 and 15 m were quantified through Pearson’s linear correlation coefficients (r). The peak bar velocity reached during the jumps with additional resistance was the variable most correlated to swimming start performance (r = -0.57 to -0.66 at 25%BW; r = -0.57 to -0.72 at 50%BW; r = -0.59 to -0.68 at 75%BW; r = -0.50 to - 0.64 at 100%BW). A few significant correlations between the parameters of the S...
Extrapolation from post-exercise measurements has been used to estimate respiratory and blood gas... more Extrapolation from post-exercise measurements has been used to estimate respiratory and blood gas parameters during exercise. This may not be accurate in exercise with reduced breathing frequency (RBF), since spontaneous breathing usually follows exercise. This study was performed to ascertain whether measurement of oxygen saturation and blood gases immediately after exercise accurately reflected their values during exercise with RBF. Eight healthy male subjects performed an incremental cycling test with RBF at 10 breaths per minute. A constant load test with RBF (B10) was then performed to exhaustion at the peak power output obtained during the incremental test. Finally, the subjects repeated the constant load test with spontaneous breathing (SB) using the same protocol as B10. Pulmonary ventilation (VE), end-tidal oxygen (PETO2), and carbon dioxide pressures (PETCO2) and oxygen saturation (SaO2) were measured during both constant load tests. The partial pressures of oxygen (PO2) a...
ABSTRACT The purpose of this study was to examine the ventilatory, gas exchange, oxygen saturatio... more ABSTRACT The purpose of this study was to examine the ventilatory, gas exchange, oxygen saturation and heart rate response to reduced breathing frequency during an incremental bicycle exercise. Eight healthy male subjects performed an incremental bicycle exercise test on an electromagnetically braked cycle ergometer twice: first with continuous breathing (CB), and second with reduced breathing frequency (B10), which was defined as 10 breaths per minute. As work rates increased, significantly higher VE, Vco2 and R were measured during the exercise with SB than during the exercise with B10. Consequently, PETco2 and PETo2 were higher and lower, respectively, during the exercise with B10 than during the exercise with SB at 150 W. In addition, HR was greater during the exercise with SB than during the exercise with B10; significant differences were achieved at 90, 120 and 150W. However, Vo2 showed no significant difference between the exercises in two different breathing conditions. In summary, reduced breathing frequency during the incremental bicycle exercise decreased VE and consequently decreased So2 and increased PETco2. However, it seemed that this degree of breathing reduction did not influence on aerobic metabolism due to unchanged Vo2.
The aim of the present study was to ascertain whether maximal 200 m front crawl swimming strategi... more The aim of the present study was to ascertain whether maximal 200 m front crawl swimming strategies and breathing patterns influenced blood gas and acid-base parameters in a manner which gives advantage to former competitive swimmers in comparison with their recreational colleagues. Twelve former competitive male swimmers (the CS group) and nine recreational male swimmers (the RS group) performed a maximal 200 m front crawl swimming with self- selected breathing pattern. Stroke rate (SR) and breathing frequency (BF) were measured during the swimming test. Measures also included blood lactate concentration ([LA]) and parameters of blood acid-base status before and during the first minute after the swimming test. The CS group swam faster then the RS group. Both groups have similar and steady SR throughout the swimming test. This was not matched by similar BF in the CS group but matched it very well in the RS group (r = 0.89). At the beginning of swimming test the CS group had low BF, ...
The purpose of the present study was to ascertain the effect of a respiratory valve (RV) and tube... more The purpose of the present study was to ascertain the effect of a respiratory valve (RV) and tubes dur-ing three different swimming tests (submaximal and maximal 200m front crawl swim and front crawl swimming to exhaustion) on a breathing frequency, selected biomechanical parameters such as stroke rate and number of breaths, and parameters of blood acid-base status and blood lactate concentration. Twelve former competitive male swimmers performed each swimming test twice: first, with an RV, and second, without an RV. Swimming with an RV induced a slower maximal 200m front crawl swim and shorter front crawl swimming to exhaustion in comparison with swimming without an RV. Furthermore, patterns of the breathing frequency during the submaximal and maximal swimming tests also differed between swimming with an RV and swimming without an RV. Significant differences of [LA-] after maximal 200m front crawl swimming between swimming with an RV and swimming without an RV (p≤0.05) were found. ...
VALVE The purpose of the present study was to ascertain the effect of a respiratory valve (RV) an... more VALVE The purpose of the present study was to ascertain the effect of a respiratory valve (RV) and tubes during three different swimming tests (submaximal and maximal 200m front crawl swim and front crawl swimming to exhaustion) on a breathing frequency, selected biomechanical parameters such as stroke rate and number of breaths, and parameters of blood acid-base status and blood lactate concentration. Twelve former competitive male swimmers performed each swimming test twice: first, with an RV, and second, without an RV. Swimming with an RV induced a slower maximal 200m front crawl swim and shorter front crawl swimming to exhaustion in comparison with swimming without an RV. Furthermore, patterns of the breathing frequency during the submaximal and maximal swimming tests also differed between swimming with an RV and swimming without an RV. Significant differences of [LA-] after maximal 200m front crawl swimming between swimming with an RV and swimming without an RV (p≤0.05) were fo...
The purpose of the present study was to ascertain the influence of reduced pulmonary ventilation ... more The purpose of the present study was to ascertain the influence of reduced pulmonary ventilation on blood acid-base balance during swimming. Five trained swimmers (age 212 years, height 1875 cm and weight 836 kg) volunteered to participate in this study. They had to swim 400 m front crawl at velocity VOBLA two times. Firstly, they were taking breath every two strokes (B2). During the second trial they swam the same distance at the similar velocity, however with reduced breathing frequency, taking breath every four strokes (B4). Measures included lactate concentration ([LA]) and parameters of blood acid-base status (pH, Po2, Pco2) before and during the third minute after the exercise. There was only Pco2 significantly increased after B4 than after B2 (p<0.05). After the exercise other parameters ([LA], pH, HCO3 and Po2) did not change significantly in response to reduced breathing frequency during swimming. It may be concluded that the reduced breathing frequency during front c...
The purpose of the present study was to ascertain the influence of reduced breathing on the blood... more The purpose of the present study was to ascertain the influence of reduced breathing on the blood acid-base status during swimming at 90% velocity of maximal 200-m front crawl. Ten swimmers (age 16.6 ± 1.8 years, height 180 ± 7 cm and weight 70 ± 7 kg) volunteered to participate in this study. They performed maximal 200-m front crawl swim. Then they performed a sub-maximal front crawl swim twice to exhaustion: first, by taking breath every two strokes (B2) and second, by taking breath every four strokes (B4). The swimming velocity was determined as 90% of maximal velocity at 200-m front crawl swim. Measures included lactate concentration ([LA]) and parameters of blood acid-base status (pH, Po2, Pco2, [HCO3-]) before and during the first and the third minute after the exercise. Swimmers swam with B2 significantly longer as they did with B4 (p < 0.05). [LA] was significantly lower after swimming with B4 than after swimming with B2 (p < 0.05). Pco2 and [HCO3-] were significantly ...
The purpose of the study was to establish whether anaerobic lactic production and oxygen uptake c... more The purpose of the study was to establish whether anaerobic lactic production and oxygen uptake could limit the energy supply during 200 m front crawl swimming. Twelve male swimmers performed four swims of 200 m crawl at intensities from 80%, 90%, 100% to 110% (until exhaustion) on separate days with a swimming snorkel. Respiratory parameters (VE, Vo2), blood parameters (pH, [LA-]) and heart rate (HR) were measured. The results demonstrate that limitations in VE, Vo2 and HR during swimming occur during supramaximal swims (no further increase in measured maximal parameters and time-constant parameters) in comparison to maximal swims. We also found limitations in the obtained maximal [LA-] and minimal pH values. It is possible to conclude that individual limitations in VE, Vo2, HR and consequently acidosis could be limiting factors of individual 200 m front crawl performances due to energy supply restrictions.
The aim of the study was to ascertain how four weeks of training with reduced breathing frequency... more The aim of the study was to ascertain how four weeks of training with reduced breathing frequency during front crawl swimming would influence a maximal 200 meters front crawl performance. Two matched groups of five recreational-level swimmers trained 5 times per week. During each swimming session breathing frequency was distinguished between the control (the B2 group was taking a breath every second stroke cycle) and an experimental (the B4 group was taking a breath every fourth stroke cycle). The swimmers performed a maximal 200 meters front crawl swim with an optional breathing pattern before and after the training. Both groups swam the maximal 200 meters front crawl after the training significantly faster then before the training. This improvement was significantly greater in the B4 group than the B2 group. B4 group swam the maximal 200 meters front crawl after the training with fewer breaths than before the training. The breathing pattern in the B2 group was unchanged by the tra...
The purpose of the present study was to ascertain whether the backward extrapolation method can b... more The purpose of the present study was to ascertain whether the backward extrapolation method can be used to calculate the pulmonary ventilation (VE) appropriate in two different breathing conditions during swimming: with and without reduced breathing frequency. Five trained swimmers swam 400 m front crawl at Onset of Blood Lactate Accumulation (OBLA) velocity taking a breath every stroke cycle (normal breathing - NB). Then they repeated 400-m front crawl at NB velocity and with NB stroke frequency taking a breath every second stroke cycle (restricted breathing - RB). The measures included the parameters of blood acid-base status (pH, Po2, Pco2, [HCO3-]) and pulmonary ventilation (VE). Pulmonary ventilation during swimming was obtained by the backward extrapolation method (VEe) and by a theoretical model (VEt). There was no significant difference between VEeand VEtin NB. But the paired t-test showed a significant (p<0,05) difference between these two parameters in RB. Pco2 was also...
We aimed to identify potential physiological and performance differences of trained cross-country... more We aimed to identify potential physiological and performance differences of trained cross-country skiers (V˙o2max=60±4 ml ∙ kg–1 ∙ min–1) following two, 3-week long altitude modalities: 1) training at moderate altitudes (600–1700 m) and living at 1500 m (LMTM;N=8); and 2) training at moderate altitudes (600–1700 m) and living at 1500 m with additional nocturnal normobaric hypoxic exposures (FiO2 =0.17;LHTM; N=8). All participants conducted the same training throughout the altitude training phase and underwent maximal roller ski trials and submaximal cyclo-ergometery before, during and one week after the training camps. No exercise performance or hematological differences were observed between the two modalities. The average roller ski velocities were increased one week after the training camps following both LMTM (p=0.03) and LHTM (p=0.04) with no difference between the two (p=0.68). During the submaximal test, LMTM increased the Tissue Oxygenation Index (11.5±6.5 to 1.0±8.5%; p=0.0...
In front crawl swimming at maximum exertion and in swimming at maximum exertion with different fo... more In front crawl swimming at maximum exertion and in swimming at maximum exertion with different forms of artificially created additional resistance, certain kinematic and dynamic parameters can be measured and the active drag, assuming that there is an equal power output in all cases can be estimated. Seventeen highly trained male swimmers, all over 16 years of age and specialized in front crawl swimming participated in this study. The pretraining mean (SE), of the height and the body mass of the subjects were 180.6+4.7 cm, and 74.3, +7 kg. The mean active drag at maximal swimming velocities ranged from 64.94 N to 76.37 N in front crawl swimming. It was found out that the forces of the active drag, calculated from the measured kinematic and dynamic parameters in front crawl sprints at maximum exertion and front crawl swimming at maximum exertion with different forms of artificially created additional resistance, were not significantly statistically different. It was concluded that th...
This study aimed to examine the correlation of different dry land strength and power tests with s... more This study aimed to examine the correlation of different dry land strength and power tests with swimming start performance. Twenty international level female swimmers (age 15.3 ± 1.6 years, FINA point score 709.6 ± 71.1) performed the track freestyle start. Additionally, dry land tests were conducted: a) squat (SJ) and countermovement jumps (CMJ), b) squat jumps with additional resistance equivalent to 25, 50, 75 and 100% of swimmers’ body weight [BW]), and c) leg extension and leg flexion maximal voluntary isometric contractions. Correlations between dry land tests and start times at 5, 10 and 15 m were quantified through Pearson’s linear correlation coefficients (r). The peak bar velocity reached during the jumps with additional resistance was the variable most correlated to swimming start performance (r = -0.57 to -0.66 at 25%BW; r = -0.57 to -0.72 at 50%BW; r = -0.59 to -0.68 at 75%BW; r = -0.50 to - 0.64 at 100%BW). A few significant correlations between the parameters of the S...
Extrapolation from post-exercise measurements has been used to estimate respiratory and blood gas... more Extrapolation from post-exercise measurements has been used to estimate respiratory and blood gas parameters during exercise. This may not be accurate in exercise with reduced breathing frequency (RBF), since spontaneous breathing usually follows exercise. This study was performed to ascertain whether measurement of oxygen saturation and blood gases immediately after exercise accurately reflected their values during exercise with RBF. Eight healthy male subjects performed an incremental cycling test with RBF at 10 breaths per minute. A constant load test with RBF (B10) was then performed to exhaustion at the peak power output obtained during the incremental test. Finally, the subjects repeated the constant load test with spontaneous breathing (SB) using the same protocol as B10. Pulmonary ventilation (VE), end-tidal oxygen (PETO2), and carbon dioxide pressures (PETCO2) and oxygen saturation (SaO2) were measured during both constant load tests. The partial pressures of oxygen (PO2) a...
ABSTRACT The purpose of this study was to examine the ventilatory, gas exchange, oxygen saturatio... more ABSTRACT The purpose of this study was to examine the ventilatory, gas exchange, oxygen saturation and heart rate response to reduced breathing frequency during an incremental bicycle exercise. Eight healthy male subjects performed an incremental bicycle exercise test on an electromagnetically braked cycle ergometer twice: first with continuous breathing (CB), and second with reduced breathing frequency (B10), which was defined as 10 breaths per minute. As work rates increased, significantly higher VE, Vco2 and R were measured during the exercise with SB than during the exercise with B10. Consequently, PETco2 and PETo2 were higher and lower, respectively, during the exercise with B10 than during the exercise with SB at 150 W. In addition, HR was greater during the exercise with SB than during the exercise with B10; significant differences were achieved at 90, 120 and 150W. However, Vo2 showed no significant difference between the exercises in two different breathing conditions. In summary, reduced breathing frequency during the incremental bicycle exercise decreased VE and consequently decreased So2 and increased PETco2. However, it seemed that this degree of breathing reduction did not influence on aerobic metabolism due to unchanged Vo2.
The aim of the present study was to ascertain whether maximal 200 m front crawl swimming strategi... more The aim of the present study was to ascertain whether maximal 200 m front crawl swimming strategies and breathing patterns influenced blood gas and acid-base parameters in a manner which gives advantage to former competitive swimmers in comparison with their recreational colleagues. Twelve former competitive male swimmers (the CS group) and nine recreational male swimmers (the RS group) performed a maximal 200 m front crawl swimming with self- selected breathing pattern. Stroke rate (SR) and breathing frequency (BF) were measured during the swimming test. Measures also included blood lactate concentration ([LA]) and parameters of blood acid-base status before and during the first minute after the swimming test. The CS group swam faster then the RS group. Both groups have similar and steady SR throughout the swimming test. This was not matched by similar BF in the CS group but matched it very well in the RS group (r = 0.89). At the beginning of swimming test the CS group had low BF, ...
The purpose of the present study was to ascertain the effect of a respiratory valve (RV) and tube... more The purpose of the present study was to ascertain the effect of a respiratory valve (RV) and tubes dur-ing three different swimming tests (submaximal and maximal 200m front crawl swim and front crawl swimming to exhaustion) on a breathing frequency, selected biomechanical parameters such as stroke rate and number of breaths, and parameters of blood acid-base status and blood lactate concentration. Twelve former competitive male swimmers performed each swimming test twice: first, with an RV, and second, without an RV. Swimming with an RV induced a slower maximal 200m front crawl swim and shorter front crawl swimming to exhaustion in comparison with swimming without an RV. Furthermore, patterns of the breathing frequency during the submaximal and maximal swimming tests also differed between swimming with an RV and swimming without an RV. Significant differences of [LA-] after maximal 200m front crawl swimming between swimming with an RV and swimming without an RV (p≤0.05) were found. ...
VALVE The purpose of the present study was to ascertain the effect of a respiratory valve (RV) an... more VALVE The purpose of the present study was to ascertain the effect of a respiratory valve (RV) and tubes during three different swimming tests (submaximal and maximal 200m front crawl swim and front crawl swimming to exhaustion) on a breathing frequency, selected biomechanical parameters such as stroke rate and number of breaths, and parameters of blood acid-base status and blood lactate concentration. Twelve former competitive male swimmers performed each swimming test twice: first, with an RV, and second, without an RV. Swimming with an RV induced a slower maximal 200m front crawl swim and shorter front crawl swimming to exhaustion in comparison with swimming without an RV. Furthermore, patterns of the breathing frequency during the submaximal and maximal swimming tests also differed between swimming with an RV and swimming without an RV. Significant differences of [LA-] after maximal 200m front crawl swimming between swimming with an RV and swimming without an RV (p≤0.05) were fo...
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