scholarly journals Physiological Responses of Continuous and Intermittent Swimming at Critical Speed and Maximum Lactate Steady State in Children and Adolescent Swimmers

Sports ◽  
2019 ◽  
Vol 7 (1) ◽  
pp. 25 ◽  
Author(s):  
Ioannis Nikitakis ◽  
Giorgos Paradisis ◽  
Gregory Bogdanis ◽  
Argyris Toubekis
Keyword(s):  
Heart Rate ◽  
Steady State ◽  
Critical Speed ◽  
Physiological Responses ◽  
Lactate Concentration ◽  
Blood Lactate Concentration ◽  
Metabolic Responses ◽  
Maximal Lactate Steady State ◽  
Children And Adolescent ◽  
Maximum Lactate

Background: The purpose of this study was to compare physiological responses during continuous and intermittent swimming at intensity corresponding to critical speed (CS: slope of the distance vs. time relationship using 200 and 400-m tests) with maximal lactate steady state (MLSS) in children and adolescents. Methods: CS and the speed corresponding to MLSS (sMLSS) were calculated in ten male children (11.5 ± 0.4 years) and ten adolescents (15.8 ± 0.7 years). Blood lactate concentration (BL), oxygen uptake ( V · O2), and heart rate (HR) at sMLSS were compared to intermittent (10 × 200-m) and continuous swimming corresponding to CS. Results: CS was similar to sMLSS in children (1.092 ± 0.071 vs. 1.083 ± 0.065 m·s−1; p = 0.12) and adolescents (1.315 ± 0.068 vs. 1.297 ± 0.056 m·s−1; p = 0.12). However, not all swimmers were able to complete 30 min at CS and BL was higher at the end of continuous swimming at CS compared to sMLSS (children: CS: 4.0 ± 1.8, sMLSS: 3.4 ± 1.5; adolescents: CS: 4.5 ± 2.3, sMLSS: 3.1 ± 0.8 mmol·L−1; p < 0.05). V · O2 and HR in continuous swimming at CS were not different compared to sMLSS (p > 0.05). BL, V · O2 and HR in 10 × 200-m were similar to sMLSS and no different between groups. Conclusion: Intermittent swimming at CS presents physiological responses similar to sMLSS. Metabolic responses of continuous swimming at CS may not correspond to MLSS in some children and adolescent swimmers.

scholarly journals THE INFLUENCE OF APNEA IN PHYSIOLOGICAL RESPONSES OF FEMALE SWIMMERS

2018 ◽  
Vol 16 (1) ◽  
pp. 149
Author(s):  
Georgia Rozi ◽  
Vassilios Thanopoulos ◽  
Milivoj Dopsaj
Keyword(s):  
Heart Rate ◽  
Physiological Responses ◽  
Lactate Concentration ◽  
Blood Lactate Concentration ◽  
Capillary Blood ◽  
Performance Time ◽  
And Performance ◽  
Underwater Movement ◽  
Sprint Swimming ◽  
Maximum Lactate

The purpose of this study was to investigate the differences in maximum concentration of lactic acid in the blood, heart rate and performance time on the test of 4x50m freestyle swimming on a sample of two protocols: a) one breath every 3 strokes and b) 14-15m of every 50m were swum with underwater movement of the feet without breathing and a rest with one breath every 3 strokes (apnea). The sample consisted of 15 female swimmers of the competitive level aged: 15.0 ± 1.0 years. Their basic style was the freestyle. To determine the maximum blood lactate concentration, capillary blood samples were taken in the 3rd, 5th, 7th minute and analyzed by the automatic analyzer Scout Lactate Germany. We also measured the heart rate immediately after each swimming protocol. The ANOVA showed that there were no statistically significant differences between the two protocols. Maximum lactate concentration in the protocol with apnea was 10.02 ± 3.05mmol / L and without apnea 8.9 ± 3.5mmol / L. Heart rate was 186 ± 6 and 186 ± 7 b/min respectively, and performance time 140.04 ± 8.13 and 138.73 ± 8.01sec in swimmers aged 14-16. Swimming apnea needs to be studied in a larger age sample with more variables to ascertain the effects on sprint swimming.

scholarly journals Agreement between heart rate deflection point and maximal lactate steady state in young adults with different body masses

2021 ◽  
Author(s):  
R. Afroundeh ◽  
P. Hofmann ◽  
S. Esmaeilzadeh ◽  
M. Narimani ◽  
A.J. Pesola
Keyword(s):  
Heart Rate ◽  
Steady State ◽  
Body Mass ◽  
Lactate Concentration ◽  
Blood Lactate Concentration ◽  
Aerobic Performance ◽  
Maximal Lactate Steady State ◽  
Young Males ◽  
Incremental Protocol ◽  
Good Agreement

AbstractWe examined the agreement between heart rate deflection point (HRDP) variables with maximal lactate steady state (MLSS) in a sample of young males categorized to different body mass statuses using body mass index (BMI) cut-off points. One hundred and eighteen young males (19.9 ± 4.4 years) underwent a standard running incremental protocol with individualized speed increment between 0.3 and 1.0 km/h for HRDP determination. HRDP was determined using the modified Dmax method called S.Dmax. MLSS was determined using 2-5 series of constant-speed treadmill runs. Heart rate (HR) and blood lactate concentration (La) were measured in all tests. MLSS was defined as the maximal running speed yielding a La increase of less than 1 mmol/L during the last 20 min. Good agreement was observed between HRDP and MLSS for HR for all participants (±1.96; 95% CI = −11.5 to +9.2 b/min, ICC = 0.88; P < 0.001). Good agreement was observed between HRDP and MLSS for speed for all participants (±1.96; 95% CI = −0.40 to +0.42 km/h, ICC = 0.98; P < 0.001). The same findings were observed when participants were categorized in different body mass groups. In conclusion, HRDP can be used as a simple, non-invasive and time-efficient method to objectively determine submaximal aerobic performance in nonathletic young adult men with varying body mass status, according to the chosen standards for HRDP determination.

scholarly journals Steady-state $$\dot{V}{\text{O}}_{2}$$ above MLSS: evidence that critical speed better represents maximal metabolic steady state in well-trained runners

2021 ◽  
Author(s):  
Rebekah J. Nixon ◽  
Sascha H. Kranen ◽  
Anni Vanhatalo ◽  
Andrew M. Jones
Keyword(s):  
Steady State ◽  
Critical Speed ◽  
Lactate Concentration ◽  
Practical Interest ◽  
Blood Lactate Concentration ◽  
Distance Runners ◽  
Severe Intensity ◽  
The Stability ◽  
Trained Runners ◽  
Over Time

AbstractThe metabolic boundary separating the heavy-intensity and severe-intensity exercise domains is of scientific and practical interest but there is controversy concerning whether the maximal lactate steady state (MLSS) or critical power (synonymous with critical speed, CS) better represents this boundary. We measured the running speeds at MLSS and CS and investigated their ability to discriminate speeds at which $$\dot{V}{\text{O}}_{2}$$ V ˙ O 2 was stable over time from speeds at which a steady-state $$\dot{V}{\text{O}}_{2}$$ V ˙ O 2 could not be established. Ten well-trained male distance runners completed 9–12 constant-speed treadmill tests, including 3–5 runs of up to 30-min duration for the assessment of MLSS and at least 4 runs performed to the limit of tolerance for assessment of CS. The running speeds at CS and MLSS were significantly different (16.4 ± 1.3 vs. 15.2 ± 0.9 km/h, respectively; P < 0.001). Blood lactate concentration was higher and increased with time at a speed 0.5 km/h higher than MLSS compared to MLSS (P < 0.01); however, pulmonary $$\dot{V}{\text{O}}_{2}$$ V ˙ O 2 did not change significantly between 10 and 30 min at either MLSS or MLSS + 0.5 km/h. In contrast, $$\dot{V}{\text{O}}_{2}$$ V ˙ O 2 increased significantly over time and reached $$\dot{V}{\text{O}}_{2\,\,\max }$$ V ˙ O 2 max at end-exercise at a speed ~ 0.4 km/h above CS (P < 0.05) but remained stable at a speed ~ 0.5 km/h below CS. The stability of $$\dot{V}{\text{O}}_{2}$$ V ˙ O 2 at a speed exceeding MLSS suggests that MLSS underestimates the maximal metabolic steady state. These results indicate that CS more closely represents the maximal metabolic steady state when the latter is appropriately defined according to the ability to stabilise pulmonary $$\dot{V}{\text{O}}_{2}$$ V ˙ O 2 .

scholarly journals Comparison of maximal lactate steady state with V2, V4, individual anaerobic threshold and lactate minimum speed in horses

2014 ◽  
Vol 66 (1) ◽  
pp. 39-46 ◽  
Author(s):  
O.A.B. Soares ◽  
G.C. Ferraz ◽  
C.B. Martins ◽  
D.P.M. Dias ◽  
J.C. Lacerda-Neto ◽  
...  
Keyword(s):  
Steady State ◽  
Anaerobic Threshold ◽  
Exercise Physiology ◽  
Lactate Concentration ◽  
Blood Lactate Concentration ◽  
Maximal Lactate Steady State ◽  
Exercise Load ◽  
Individual Anaerobic Threshold ◽  
Minimum Speed ◽  
Lactate Minimum

The anaerobic threshold is a physiologic event studied in various species. There are various methods for its assessment, recognized in the human and equine exercise physiology literature, several of these involving the relationship between blood lactate concentration (LAC) and exercise load, measured in a standardized exercise test. The aim of this study was to compare four of these methods: V2, V4, individual anaerobic threshold (IAT) and lactate minimum speed (LMS) with the method recognized as the gold standard for the assessment of anaerobic threshold, maximal lactate steady-state (MLSS). The five tests were carried out in thirteen trained Arabian horses, in which velocities and associated LAC could be measured. The mean velocities and the LAC associated with the anaerobic threshold for the five methods were respectively: V2 = 9.67±0.54; V4 = 10.98±0.47; V IAT = 9.81±0.72; V LMS = 7.50±0.57 and V MLSS = 6.14±0.45m.s-1 and LAC IAT = 2.17±0.93; LAC LMS = 1.17±0.62 and LAC MLSS = 0.84±0.21mmol.L-1. None of the velocities were statistically equivalent to V MLSS (P<0.05). V2, V4 and V LMS showed a good correlation with V MLSS , respectively: r = 0.74; r = 0.78 and r = 0.83, and V IAT did not significantly correlate with V MLSS. Concordance between the protocols was relatively poor, i.e., 3.28±1.00, 4.84±0.30 and 1.43±0.32m.s-1 in terms of bias and 95% agreement limits for V2, V4 and LMS methods when compared to MLSS. Only LAC LMS did not differ statistically from LAC MLSS. Various authors have reported the possibility of the assessment of anaerobic threshold using rapid protocols such as V4 and LMS for humans and horses. This study corroborates the use of these tests, but reveals that adjustments in the protocols are necessary to obtain a better concordance between the tests and the MLSS.

Maximal Lactate Steady State in Children

1996 ◽  
Vol 8 (4) ◽  
pp. 328-336 ◽  
Author(s):  
Ralph Beneke ◽  
Volker Schwarz ◽  
Renate Leithäuser ◽  
Matthias Hütler ◽  
Serge P. von Duvillard
Keyword(s):  
Steady State ◽  
Lactate Concentration ◽  
Blood Lactate Concentration ◽  
Peak Heart Rate ◽  
Maximal Lactate Steady State ◽  
Specific Test ◽  
Testing Procedures ◽  
Time Courses ◽  
Kinetics Of ◽  
Submaximal Workload

Maximal lactate steady state (MLSS) corresponds to the prolonged constant workload whereby the kinetics of blood lactate concentration clearly increases from steady state. Different results of MLSS in children may reflect specific test protocols or definitions. Three methods corresponding to lactate time courses during 20 min (MLSS I), 16 min (MLSS II), and 8 min (MLSS III) of constant submaximal workload were intraindividually compared in 10 boys. At MLSS I, lactate, V̇O2peak, heart rate, and workload were higher (p < .05) than at MLSS II and at MLSS III. The differences between MLSS I, MLSS II, and MLSS III reflect insufficient contribution to lactate kinetics by testing procedures, strongly depending on the lactate time courses during the initial 10 min of constant workload. Previously published divergent results of MLSS in children seem to reflect a methodological effect more than a metabolic change.

Predicting Maximal Lactate Steady State in Children and Adults

2009 ◽  
Vol 21 (4) ◽  
pp. 493-505 ◽  
Author(s):  
Ralph Beneke ◽  
Hermann Heck ◽  
Helge Hebestreit ◽  
Renate M Leithäuser
Keyword(s):  
Steady State ◽  
Blood Lactate ◽  
Lactate Concentration ◽  
Blood Lactate Concentration ◽  
Load Test ◽  
Maximal Lactate Steady State ◽  
Test Power ◽  
Load Tests

The value of blood lactate concentration (BLC) measured during incremental load tests in predicting maximal lactate-steady-state (MLSS) workload has rarely been investigated in children. In 17 children and 18 adults MLSS was 4.1 ± 0.9mmol 1.1. Workload at BLC of 3.0mmol 1.1 determined during an incremental load test explained about 80% of the variance (p < .001) and best predicted MLSS workload independent of age. This was despite the increase in power per time related to maximum incremental load test power being higher (p < .001) in children than in adults. The BLC response to given exercise intensities is faster in children without affecting MLSS.

scholarly journals Acute Physiological Responses to Ultra Short Race‐Pace Training in Competitive Swimmers

2020 ◽  
Vol 75 (1) ◽  
pp. 95-102
Author(s):  
David Williamson ◽  
Earl McCarthy ◽  
Massimiliano Ditroilo
Keyword(s):  
Heart Rate ◽  
Blood Lactate ◽  
Physiological Responses ◽  
Lactate Concentration ◽  
Blood Lactate Concentration ◽  
High Volume ◽  
High Heart Rate ◽  
Training Modality ◽  
Before And After ◽  
Rate Profile

Abstract Ultra Short Race Pace training (USRPT) is an emerging training modality devised in 2011 to deviate from high-volume swimming training that is typically prescribed. USRPT aims to replicate the exact demands of racing, through its unique prescription of race-pace velocity sets with short rest intervals. It has been surmised, with little physiological evidence, that USRPT provides swimmers with the best opportunity to optimize the conditioning, technique, and psychology aspects of racing at the most specific velocity of the relevant event, with low blood lactate concentration. The aim of this study was to examine acute physiological responses of USRPT. Fourteen swimmers were recruited to perform a USRPT set: 20 x 25 m freestyle with a 35-s rest interval. Swimmers were required to maintain the velocity of their 100 m personal best time for each sprint. Sprint performance, blood lactate, heart rate and the RPE were measured. Blood lactate was taken before, during (after every 4 sprints) and 3 minutes after the USRPT protocol. Heart rate monitors were used to profile the heart rate. Athletes reported the RPE before- and after completion of the USRPT set. Sprint times increased by 3.3-10.8% when compared to the first sprint (p < 0.01). There was high blood lactate concentration (13.6 ± 3.1mmol/l), a significant change in the RPE from 8 ± 1.6 to 18 ± 1.6 (p < 0.01) and a substantially high heart rate profile with an average HRmax of 188 ± 9 BPM. The results show the maximal intensity nature of USRPT and portray it as an anaerobic style of training.

scholarly journals A 1-day maximal lactate steady-state assessment protocol for trained cyclists

2018 ◽  
Vol 7 (1) ◽  
pp. 9-16
Author(s):  
Jose Ramon Lillo-Bevia ◽  
Ricardo Moran-Navarro ◽  
Alejandro Martinez-Cava ◽  
Victor Cerezuela ◽  
Jesus G. Pallares
Keyword(s):  
Steady State ◽  
Data Analysis ◽  
Lactate Concentration ◽  
Blood Lactate Concentration ◽  
Constant Load ◽  
Load Test ◽  
Validity And Reliability ◽  
Maximal Lactate Steady State ◽  
Exercise Tests ◽  
Assessment Protocol

The main aim of this study is to assess the validity of a new cycling protocol to estimate the Maximal Lactate Steady-State workload (MLSS) through a one-day incremental protocol (1day_MLSS). Eleven well-trained male cyclists performed 3 to 4 trials of 30-min constant load test (48-72h in between) to determine their respective MLSS workload. Then, on separate days, each cyclist carried out two identical graded exercise tests, comprised of four 10-minute long stages, with the initial load at 63% of their respective maximal aerobic power, 0.2 W·Kg-1 increments, and blood lactate concentration (BLC) determinations each 5 min. The results of the 1day_MLSS tests were analysed through three different constructs: i) BLC difference between 5th and 10th min of each stage (DIF_5to10), ii) BLC difference between the 10th min of two consecutive stages (DIF_10to10), and iii) difference in the mean BLC between the 5th and 10th min of two consecutive stages (DIF_mean). For all constructs, the physiological steady state was determined as the highest workload that could be maintained with a BLC rise lower than 1mmol·L-1.  No significant differences were detected between the MLSS workload (247 ± 22W) and any of the 1day_MLSS data analysis (250 ± 24W, 245 ± 23W and 243 ± 21W, respectively; p>0.05). When compared to the MLSS workload, strong ICCs and low bias values were found for these three constructs, especially for the DIF_10to10 workload (r=0.960; Bias=2.2 W). High within-subject reliability data were found for the DIF10_10 construct (ICC=0.846; CV=0.4%; Bias=2.2 ± 6.4W). The 1day_MLSS test and DIF_10to10 data analysis is a valid assessment to predict the MLSS workload in cycling, that considerably reduces the dedicated time, effort and human resources that requires the original test. The validity and reliability values reported in this project are higher than those achieved by other previous MLSS estimation tests.

Sign in / Sign up

Export Citation Format

Share Document