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1.
Int J Sports Med ; 45(8): 598-607, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38648801

RESUMO

This study aimed (i) to analyze the 1500 m open water swimming performance, (ii) to examine the associations between physiological and biomechanical variables with swimming performance, and (iii) to determine which variables can predict swimming performance in triathletes. Fourteen elite triathletes (23.4±3.8 y) performed a 1500 m test in open water swimming conditions. Swimming performance was assessed using World Aquatics Points Scoring, and data were obtained from the 1500 m open water swimming test. Heart rate, end-exercise oxygen uptake (EE˙VO2) and blood lactate concentrations were measured. The initial 250 m of the 1500 m swimming test presented the highest values of biomechanical variables in males (i. e. swimming speed, stroke rate (SR), length (SL), index (SI)). A decrease in SL was observed in the last 250 m in both sexes. Positive association were found between EE˙VO2 (r=0.513; p=0.030), swimming speed (r=0.873; p<0.001) and SI (r=0.704; p=0.002) with swimming performance. In contrast, time constant of the oxygen uptake (r=-0.500; p=0.034) and buoy-turn times (r=-0.525; p=0.027) were negatively associated with performance. SI was the main predictor (R 2=0.495) of open water swimming performance in triathletes. In conclusion, triathletes and coaches must conduct open water training sessions to maximize SI (i. e. swimming efficiency).


Assuntos
Desempenho Atlético , Frequência Cardíaca , Ácido Láctico , Consumo de Oxigênio , Natação , Humanos , Natação/fisiologia , Masculino , Consumo de Oxigênio/fisiologia , Desempenho Atlético/fisiologia , Adulto Jovem , Ácido Láctico/sangue , Frequência Cardíaca/fisiologia , Fenômenos Biomecânicos , Feminino , Adulto , Teste de Esforço
2.
J Sports Sci Med ; 23(1): 25-33, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38455440

RESUMO

This study aimed to analyze the power profile (PP) during the cycling segment of international-level triathletes in the World Triathlon Series (WTS) and Olympics and to evaluate the influence of circuit type, race distance (Sprint or Olympic distance) and race dynamics on the development of the cycling leg and the final race position. Four male triathletes participated in the study. Twenty races were analyzed using geolocation technology and power-meter data to analyze PP, race dynamics, and course characteristics. Before the races, incremental tests of volitional exhaustion with gas analysis were performed to determine power intensity zones. Nonparametric Mann-Whitney U tests and correlation analyses were conducted to identify differences and relationships between various variables. A correlation between the time spent above maximal aerobic power (MAP) and dangerous curves per kilometer (r = 0.46; p < 0.05) and bike split result (BSR) (r = -0.50; p < 0.05) was observed. Also, moderate correlation was found between BSR and the final race position (r = 0.46; p < 0.01). No differences were found between sprint and Olympic distance races in any variable. Power output variability, influenced by technical circuit segments, remains the main characteristic in international short-distance races. The results of the present study suggest that the triathletes who are better adapted to intermittent high intensity efforts perform better cycling legs at international high-level races.


Assuntos
Ciclismo , Corrida , Humanos , Masculino , Natação , Fatores de Tempo
3.
Scand J Med Sci Sports ; 33(12): 2444-2456, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37632141

RESUMO

OBJECTIVE: The sports-science literature lacks data on training and performance characteristics of international elite athletes over multiple seasons. The present case study provided general training characteristics and performance data of two male short-distance triathletes in the Junior, U23, and international Elite categories. METHODS: General training and performance data of two male elite triathletes were described in swimming, cycling, and running segments from the 2015 to 2022 season. The training load was presented using the ECO model while the training intensity distribution (TID) was a triphasic model. RESULTS: Both triathletes increased their performance throughout the seasons. Triathlete A increased his VO2max in cycling by 20.6%, in running by 16.7%. His power at VO2max and his speed at VO2max by 18.9% and 11.0%, respectively. Triathlete B improved his VO2max by 17.8% in cycling, by 16.1% in running and his power at VO2max by 24%, and his speed at VO2max by 14.3%. The triathletes trained on average 14-17 h a week. The TID model was polarized. CONCLUSIONS: To achieve the top international level, it is necessary to consider the following measures: training load progression; improvements in physiological variables; and participation in international events starting from youth categories.


Assuntos
Consumo de Oxigênio , Resistência Física , Adolescente , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Resistência Física/fisiologia , Natação/fisiologia , Ciclismo/fisiologia
4.
Sensors (Basel) ; 20(5)2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32110939

RESUMO

The aim of this study was to evaluate changes in electromyographic activity with the use of gradual compression stockings (GCSs) on middle-distance endurance athletes' performance, based on surface electromyography measurement techniques. Sixteen well-trained athletes were recruited (mean ± SD: age 33.4 ± 6.3 years, VO2max 63.7 ± 6.3 mL·kg-1·min-1, maximal aerobic speed 19.7 ± 1.5 km·h). The athletes were divided into two groups and were assigned in a randomized order to their respective groups according to their experience with the use of GCSs. Initially, a maximum oxygen consumption (VO2max) test was performed to standardize the athletes' running speeds for subsequent tests. Afterward, electromyographic activity, metabolic, and performance variables for each group were measured with surface electromyography. In addition, blood lactate concentration was measured, both with and without GCSs, during 10 min at 3% above VT2 (second ventilatory threshold), all of which were performed on the track. Next, surface electromyography activity was measured during a 1 km run at maximum speed. No significant changes were found in electromyography activity, metabolic and performance variables with GCSs use (p > 0.164) in any of the variables measured. Overall, there were no performance benefits when using compression garments against a control condition.


Assuntos
Atletas , Músculos/fisiologia , Corrida/fisiologia , Meias de Compressão , Adulto , Eletromiografia , Feminino , Humanos , Perna (Membro)/fisiologia , Masculino
5.
J Sports Sci Med ; 18(4): 708-715, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31827355

RESUMO

The purpose of the present study was to relate the training intensity distribution with performance in a Half-Ironman distance triathlon competition. A total of 18 recreational-level triathletes were divided into two training groups according to their training intensity distribution: Polarized (POL) and Pyramidal (PYR). Prior to the specific training period of the study, subjects performed a ramp-protocol test, running and cycling to determine ventilatory thresholds (VT) through gas-exchange analysis. For swimming, subjects performed an 800-metre test to establish their training zones. Training was quantified based on the cumulative time spent in 3 intensity zones: zone 1 (low intensity, VT2). POL competed 84.5%/4.2%/11.3% and PYR 77.9%/18.8%/3.3% of total training time for zones 1,2 and 3 respectively. The goal of the training period was a half Ironman distance triathlon. Training time in zone 2 inversely correlated with swimming and cycling race time in POL and with running and total race time in PYR. Power at VT2 on bike and speed at VT2 as well as maximum aerobic power and speed in the physiological post test inversely correlated with bike and run segment respectively and with total race time. These results suggest that training time in zone 2 was related with better performance on a Half-Ironman race in amateur triathletes. Future experimental research is needed to clarify the importance of training intensity distribution regarding performance.


Assuntos
Ciclismo/fisiologia , Comportamento Competitivo/fisiologia , Condicionamento Físico Humano/métodos , Resistência Física/fisiologia , Corrida/fisiologia , Natação/fisiologia , Adulto , Limiar Anaeróbio/fisiologia , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Troca Gasosa Pulmonar/fisiologia , Adulto Jovem
6.
Sports (Basel) ; 12(2)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38393273

RESUMO

(1) Background: There is a lack of data on the long-term training characteristics and performance markers of elite young female endurance athletes. The aim of this study was to present the training load (ECOs), as well as the evolution of the anthropometric values and performance of three elite U23 female triathletes over a season. (2) Methods: General training data and performance data relating to the swimming, cycling, and running legs of the 2021 season were described. The training intensity distribution (TID) was presented using the triphasic model, while the training load was based on the ECO model. An anthropometric analysis was also conducted in accordance with the ISAK standards. (3) Results: Triathletes increased their VO2max in cycling (6.9-10%) and running (7.1-9.1%), as well as their power and speed associated with the VO2max (7.7-8.6% in cycling and 5.1-5.3% in running) and their swimming speed associated with the lactate thresholds (2.6-4.0% in LT2 and 1.2-2.5% in LT1). The triathletes completed more than 10 h of weekly average training time, with peak weeks exceeding 15 h. The average TID of the three triathletes was 82% in phase 1, 6% in phase 2, and 12% in phase 3. A decrease in the sum of skinfolds and fat mass percentage was observed during the season in the three triathletes, although the last measurement revealed a stagnation or slight rise in these parameters. (4) Conclusions: The triathletes performed a combination of two training periodization models (traditional and block periodization) with a polarized TID in most of the weeks of the season. Improvements in performance and physiological parameters were observed after the general preparatory period as well as a positive body composition evolution throughout the season, except at the end, where the last measurement revealed stagnation or a slight decline. This study can be useful as a general guide for endurance coaches to organize a training season with female U23 triathletes.

7.
J Funct Morphol Kinesiol ; 8(4)2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38132720

RESUMO

The capacity of laboratory tests to predict competition performance has been broadly researched across several endurance sports. The aim of the present study was to analyse how pool swimming performance can predict the result of the swimming segment in triathlon competitions and compare predictability differences based on competition level and distance. Eighteen male triathletes participated in the study. Three were ranked world-class, ten elite/international level, and five highly trained/national level. A total of sixty-one graded multi-stage swimming tests were conducted. Blood lactate was measured to calculate the following hypothetical predictor variables: speed at lactate threshold 1 (LT1), speed at lactate threshold 2 (LT2), and speed in the last repetition of the test (SL200). The following data were collected for a total of 75 races: time in the swimming leg (TSL); position after the swimming leg (PSL); time difference with the first triathlete after the swimming leg (DFT); and final race position. The race levels were divided according to participant levels as follows: world series (WS) (n = 22); World Cup (WC) (n = 22); Continental Cup (CC) (n = 19); national championship (N) (n = 5); and local race (L) (n = 5). Based on distance, they were divided into Olympic distance (OD) (n = 37) and sprint distance (SD) (n = 38). A moderate to strong positive association was found between LT1, LT2, SL200 and PSL and TSl at all race levels except for the SD CC, SD WC, and OD CC races, where no or weak-to-moderate correlations were found. The present study demonstrated that performance measured in a graded multi-stage pool lactate test can predict performance in a triathlon swimming segment. This finding is highly useful for coaches as it can help them to obtain a reliable measure of the triathlete's specific capabilities in the swimming leg.

8.
Int J Sports Physiol Perform ; 18(11): 1328-1335, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37689400

RESUMO

PURPOSE: To analyze the associations between physiological and biomechanical variables with the FINA (International Swimming Federation) points (ie, swimming performance) obtained in 1500-m front-crawl swimming to determine whether these variables can be used to explain triathletes' FINA points. METHODS: Fourteen world-class, international and national triathletes (10 male: 23.24 [3.70] y and 4 female: 23.36 [3.76] y) performed a 1500-m front-crawl swimming test in a short-course pool. Heart rate (HR), oxygen uptake (V˙O2), and blood lactate concentrations were obtained before and after the test. HR was also measured during the effort. Highest V˙O2 value (V˙O2peak) was estimated by extrapolation. Clean swimming speed, turn performance, stroke rate, stroke length, and stroke index (SI) were obtained by video analysis. RESULTS: Average 1500-m performance times were 1088 (45) seconds and 1144 (31) seconds for males and females, respectively. HR after the effort, V˙O2peak, aerobic contributions, total energy expenditure, energy cost, and turn performance presented moderate negative associations with swimming performance (r ≈ .5). In contrast, respiratory exchange ratio, anaerobic alactic contribution, clean swimming speed, stroke length, and SI were positively related, with clean swimming speed and SI having a strong large association (r ≈ .7). A multiple stepwise regression model determined that 71% of the variance in FINA points was explained by SI and total energy expenditure, being predictors in 1500-m front-crawl swimming. CONCLUSIONS: Swimming performance in triathletes was determined by the athletes' energy demands and biomechanical variables. Thus, coaches should develop specific technique skills to improve triathletes' swimming efficiency.


Assuntos
Ácido Láctico , Natação , Humanos , Masculino , Feminino , Natação/fisiologia , Fenômenos Biomecânicos/fisiologia , Atletas
9.
Front Physiol ; 13: 835705, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35514361

RESUMO

There is a growing interest in the scientific literature for reporting top-class endurance athletes training programs. This case study reports on the training program of a world-class male triathlete preparing to compete in the Tokyo 2020 Olympic Games. A macrocycle of 43 weeks is presented. The triathlete performed 14.74 ± 3.01 h of weekly endurance training volume. Training intensity distribution (TID) was 81.93% ± 6.74%/7.16% ± 2.03%/10.91% ± 6.90% for zones 1 (low intensity, VT2) respectively. Pyramidal TID model is observed during the initial stages of the periodization and Polarized TID model is observed at the end of the macrocycle. The triathlete's peak ⩒O2 was increased by 20% on cycling and by 14% on running. Peak power was increased by 3.13% on cycling test and peak speed by 9.71% on running test. Finally, the triathlete placed 12th in Olympic distance and 10th in Mixed Relay in Tokyo 2020 Olympic games.

10.
Artigo em Inglês | MEDLINE | ID: mdl-35409555

RESUMO

The number of participants in popular races has increased in recent years, with most of them being amateurs. In addition, it has been observed that there is a high percentage of injuries among them, and some of these injuries may be related to a low stride frequency. The aim of this research was to check if a continuous running training program with a musical base improves the stride frequency of popular runners. For this purpose, the effect of a 6 week continuous running training program with the help of a musical track with a constant rhythm that was 10% higher than the preferred stride frequency of the subjects was analyzed and compared to a control group that performed the continuous running training without sound stimuli. Significant increases were found in the evolution of stride frequency in the experimental group between the pre- and post-test (p = 0.002). No significant changes were observed in the stride frequency of the control group. These results show that training with music feedback helps to improve stride frequency in recreational runners. Future research should study the evolution of the improvement obtained in time as it is unknown if the increase in stride rate has been integrated in the runner's technique, making the improvement obtained permanent. Future research is needed to confirm these results by enlarging the sample and carrying out an exhaustive biomechanical study.


Assuntos
Música , Corrida , Fenômenos Biomecânicos , Retroalimentação , Marcha , Humanos , Corrida/lesões
11.
J Strength Cond Res ; 25(2): 511-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20224447

RESUMO

This study analyzed and compared the exercise intensity exerted by Youth and Junior cyclists in single-day and stage races. Heart rate was measured during the races and categorized according to 3 intensity zones: Z1 (below the ventilatory threshold [VT]), Z2 (between the VT and the respiratory compensation threshold [RCT]), and Z3 (above the RCT). The training impulse (TRIMP) was calculated by multiplying the sum of the time spent in each zone by 1, 2, and 3, respectively. Time spent in Z1, Z2, and daily TRIMP were significantly higher (p < 0.05) in Junior than in Youth in both single-day races (21.6 ± 1.9 min vs. 14.8 ± 1.6 min, 55.4 ± 2.3 min vs. 34.7 ± 1.9 min, and 257 ± 6 vs. 194 ± 6, respectively) and stage races (49.2 ± 3.4 min vs. 23.5 ± 4.7 min, 51.2 ± 2.6 min vs. 35.3 ± 3.7 min, and 201 ± 10 vs. 147 ± 7, respectively). In Youth and Junior, time and percentage time spent in Z3 and daily TRIMP were also significantly higher (p < 0.05) in single-day races (39.0 ± 1.9 min, 40.2 ± 1.9% and 225 ± 7) than in stage races (13.9 ± 1.8 min, 15.2 ± 1.8% and 174 ± 8). In conclusion, the present study showed that races in both Youth and Junior categories are highly demanding and that their intensity and exercise load are related to the total race duration.


Assuntos
Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Frequência Cardíaca/fisiologia , Consumo de Oxigênio/fisiologia , Adolescente , Limiar Anaeróbio/fisiologia , Comportamento Competitivo , Metabolismo Energético/fisiologia , Humanos , Masculino , Educação Física e Treinamento/métodos , Esforço Físico/fisiologia , Fatores de Tempo , Adulto Jovem
12.
Percept Mot Skills ; 112(1): 21-8, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21466077

RESUMO

The aim of this study was to analyse and compare movement pattems and direction of locomotion in professional men's beach volleyball. A quantitative analysis of beach volleyball play was carried out for 10 players in the European Beach Volleyball Championship 2005. Video recordings were made of the 1,997 movements in 4 matches. Analysis showed that male players used more offensive than defensive movement patterns. Defensive movement patterns were more blocks and defense than receptions. Offensive movement patterns were more attack and placements than attack preparation moves. Advance was the direction of locomotion most used. Identifying and understanding such movement patterns are vital to defining specific, effective training strategies for men's beach volleyball players.


Assuntos
Atletas , Atividade Motora/fisiologia , Movimento/fisiologia , Adulto , Humanos , Masculino , Gravação em Vídeo , Voleibol
13.
J Hum Kinet ; 67: 185-198, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31523317

RESUMO

The number of recreational athletes completing a Half-Ironman triathlon has increased exponentially in recent years. However, there is a lack of research on how to train for this kind of an event. The purpose of this study was thus to analyse triathletes' changes in performance and body composition following a triathlon-specific training period. Fourteen male amateur triathletes completed a 7-week period of general training and a 13-week period of specific training for a Half-Ironman triathlon. Anthropometric measures and performance tests were carried out to assess the effects of the specific training program. Results showed that the pre-test value of VO2max for cycling was inversely correlated not only with the percentage of change in cycling performance, but also with the percentage change in several variables of running performance. In swimming, inverse correlations were observed between the time of the first 800 m test and the time percentage change for this test, but not with the percentage change in the performance of other segments of the race. Moreover, the somatotype component of endomorphy and the fat mass percentage of the first anthropometry were highly correlated with the percentage change in VO2max in the run segment. These results highlight the importance of providing individualised training, considering that the same training program had a different impact on recreational triathletes belonging to the same group. Amateur athletes with higher initial performance levels probably need a greater amount of training to achieve improved adaptation.

14.
J Hum Kinet ; 65: 187-195, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30687430

RESUMO

To compare the effect of three different feedback modalities on swimming pace, sixteen male swimmers and triathletes participated in this study. Each participant swam 3 x 400 m, one for each feedback modality, swimming front crawl at 80% of their individual swimming critical speed. Three feedback modalities were examined: self-pacing, real time visual feedback and real time voice feedback. The swimmers adopted a fast start in all feedback modalities. In the real time voice feedback modality, the data recorded during the second lap (200 m) showed a significant improvement of their swimming pace approaching the swimming pace intended (-1.47 s, p < .01, medium effect size 0.79). A significant improvement toward the swimming pace intended was also noticed at the third split time (300 m) (0.05 s, p < .01, large effect size 0.81) and at the fourth split time (400 m) (0.46 s, p < .01, medium effect size 0.76). In self-pacing, the swimmers were not able to swim in line with the swimming pace intended. In real time visual feedback modality, the swimmers did not show a significant improvement approaching the swimming pace intended. The results revealed that communication with the swimmers using the real time voice feedback induced a significant improvement in their swimming pace and could help the athletes to swim with accurate and consistent pace.

15.
Food Funct ; 9(1): 463-475, 2018 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-29231216

RESUMO

In the present study, we examined whether particular urinary oxylipins (isoprostanes (IsoPs), leukotrienes (LTs), prostaglandins (PGs), and thromboxanes (TXs)) in 16 elite triathletes could alter during 145 days of training. Within this time span, 45 days were dedicated to examining the effects of the intake of a beverage rich in polyphenols (one serving: 200 mL per day) supplemented in their diet. The beverage was a mixture of citrus juice (95%) and Aronia melanocarpa juice (5%) (ACJ). Fifty-two oxylipins were analyzed in the urine. The quantification was carried out using solid-phase extraction, liquid chromatography coupled with triple quadrupole mass spectrometry. The physical activity decreased the excretion of some PG, IsoP, TX, and LT metabolites from arachidonic acid, γ-dihomo-linolenic acid, and eicosapentaenoic acid. The ACJ also reduced the excretion of 2,3-dinor-11ß-PGF2α and 11-dehydro-TXB2, although the levels of other metabolites increased after juice supplementation (PGE2, 15-keto-15-F2t-IsoP, 20-OH-PGE2, LTE4, and 15-epi-15-E2t-IsoP), compared to the placebo. The metabolites that increased in abundance have been related to vascular homeostasis and smooth muscle function, suggesting a positive effect on the cardiovascular system. In conclusion, exercise influences mainly the decrease in oxidative stress and the inflammation status in elite triathletes, while ACJ supplementation has a potential benefit regarding the cardiovascular system that is connected in a synergistic manner with elite physical activity.


Assuntos
Citrus/metabolismo , Sucos de Frutas e Vegetais/análise , Metabolismo dos Lipídeos , Oxilipinas/urina , Photinia/metabolismo , Adulto , Atletas , Sistema Cardiovascular/metabolismo , Cromatografia Líquida de Alta Pressão , Citrus/química , Feminino , Humanos , Lipídeos/química , Masculino , Estresse Oxidativo , Photinia/química , Treinamento Resistido , Adulto Jovem
16.
Front Physiol ; 8: 298, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28611674

RESUMO

Purpose: To compare the absolute and relative training load of the Marathon (42k) and the Ironman (IM) training in recreational trained athletes. Methods: Fifteen Marathoners and Fifteen Triathletes participated in the study. Their performance level was the same relative to the sex's absolute winner at the race. No differences were presented neither in age, nor in body weight, height, BMI, running VO2max max, or endurance training experience (p > 0.05). They all trained systematically for their respective event (IM or 42k). Daily training load was recorded in a training log, and the last 16 weeks were compared. Before this, gas exchange and lactate metabolic tests were conducted in order to set individual training zones. The Objective Load Scale (ECOs) training load quantification method was applied. Differences between IM and 42k athletes' outcomes were assessed using Student's test and significance level was set at p < 0.05. Results: As expected, Competition Time was significantly different (IM 11 h 45 min ± 1 h 54 min vs. 42k 3 h 6 min ± 28 min, p < 0.001). Similarly, Training Weekly Avg Time (IM 12.9 h ± 2.6 vs. 42k 5.2 ± 0.9), and Average Weekly ECOs (IM 834 ± 171 vs. 42k 526 ± 118) were significantly higher in IM (p < 0.001). However, the Ratio between Training Load and Training Time was superior for 42k runners when comparing ECOs (IM 65.8 ± 11.8 vs. 42k 99.3 ± 6.8) (p < 0.001). Finally, all ratios between training time or load vs. Competition Time were superior for 42k (p < 0.001) (Training Time/Race Time: IM 1.1 ± 0.3 vs. 42k 1.7 ± 0.5), (ECOs Training Load/Race Time: IM 1.2 ± 0.3 vs. 42k 2.9 ± 1.0). Conclusions: In spite of IM athletes' superior training time and total or weekly training load, when comparing the ratios between training load and training time, and training time or training load vs. competition time, the preparation of a 42k showed to be harder.

17.
Front Physiol ; 7: 138, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27148076

RESUMO

PURPOSE: We investigated the changes in physiological and performance parameters after a Live High-Train Low (LHTL) altitude camp in normobaric (NH) or hypobaric hypoxia (HH) to reproduce the actual training practices of endurance athletes using a crossover-designed study. METHODS: Well-trained triathletes (n = 16) were split into two groups and completed two 18-day LTHL camps during which they trained at 1100-1200 m and lived at 2250 m (P i O2 = 111.9 ± 0.6 vs. 111.6 ± 0.6 mmHg) under NH (hypoxic chamber; FiO2 18.05 ± 0.03%) or HH (real altitude; barometric pressure 580.2 ± 2.9 mmHg) conditions. The subjects completed the NH and HH camps with a 1-year washout period. Measurements and protocol were identical for both phases of the crossover study. Oxygen saturation (S p O2) was constantly recorded nightly. P i O2 and training loads were matched daily. Blood samples and VO2max were measured before (Pre-) and 1 day after (Post-1) LHTL. A 3-km running-test was performed near sea level before and 1, 7, and 21 days after training camps. RESULTS: Total hypoxic exposure was lower for NH than for HH during LHTL (230 vs. 310 h; P < 0.001). Nocturnal S p O2 was higher in NH than in HH (92.4 ± 1.2 vs. 91.3 ± 1.0%, P < 0.001). VO2max increased to the same extent for NH and HH (4.9 ± 5.6 vs. 3.2 ± 5.1%). No difference was found in hematological parameters. The 3-km run time was significantly faster in both conditions 21 days after LHTL (4.5 ± 5.0 vs. 6.2 ± 6.4% for NH and HH), and no difference between conditions was found at any time. CONCLUSION: Increases in VO2max and performance enhancement were similar between NH and HH conditions.

18.
Food Funct ; 7(10): 4343-4355, 2016 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-27713956

RESUMO

The aim of the this study was to determine the effect of a polyphenols-rich juice (aronia-citrus juice, ACJ) on F4-neuroprostanes and F2-dihomo-isoprostanes-markers of oxidative stress associated with the central nervous system (CNS)-in 16 elite triathletes under a controlled diet for triathlon training (145 days). In the triathletes, a decrease of the lipid peroxidation markers after ACJ intake, associated with neuronal membrane degradation (10-epi-10-F4t-neuroprostane and 10-F4t-neuroprostane), was observed when compared with placebo stage values. Regarding the F2-dihomo-isoprostanes, a significant decrease of the neuromotor system damage biomarkers (17-F2t-dihomo-isoprostane) with an increase of training load during the study was observed, although the decrease of the load training at the last stage showed a significant increase of the values of ent-7-(RS)-7-F2t-dihomo-IsoP, suggesting a possible role in adaptation post-training. On the other hand, the changes in the excretion of 17-epi-17-F2t-dihomo-IsoP provided a positive connection between physical exercise and ACJ intake. Thus, the results showed in this clinical study in young triathletes will help to elucidate novel interactions and mechanisms between the excretion of lipid peroxidation metabolites from CNS, supplementation of polyphenols-rich juice in the diet and physical exercise during a training season.


Assuntos
Suplementos Nutricionais , Sucos de Frutas e Vegetais/análise , Estresse Oxidativo/efeitos dos fármacos , Polifenóis/farmacologia , Esportes , Adolescente , Adulto , Biomarcadores/sangue , Citrus/química , Feminino , Humanos , Isoprostanos , Masculino , Neuroprostanos , Photinia/química , Polifenóis/administração & dosagem , Polifenóis/química , Adulto Jovem
19.
Free Radic Res ; 50(5): 485-94, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26503242

RESUMO

This randomized and controlled trial investigated whether the increase in elite training at different altitudes altered the oxidative stress biomarkers of the nervous system. This is the first study to investigate four F4-neuroprostanes (F4-NeuroPs) and four F2-dihomo-isoprostanes (F2-dihomo-IsoPs) quantified in 24-h urine. The quantification was carried out by ultra high pressure liquid chromatography-triple quadrupole-tandem mass spectrometry (UHPLC-QqQ-MS/MS). Sixteen elite triathletes agreed to participate in the project. They were randomized in two groups, a group submitted to altitude training (AT, n = 8) and a group submitted to sea level training (SLT) (n = 8), with a control group (Cg) of non-athletes (n = 8). After the experimental period, the AT group triathletes gave significant data: 17-epi-17-F2t-dihomo-IsoP (from 5.2 ± 1.4 µg/mL 24 h(-1) to 6.6 ± 0.6 µg/mL 24 h(-1)), ent-7(RS)-7-F2t-dihomo-IsoP (from 6.6 ± 1.7 µg/mL 24 h(-1) to 8.6 ± 0.9 µg/mL 24 h(-1)), and ent-7-epi-7-F2t-dihomo-IsoP (from 8.4 ± 2.2 µg/mL 24 h(-1) to 11.3 ± 1.8 µg/mL 24 h(-1)) increased, while, of the neuronal degeneration-related compounds, only 10-epi-10-F4t-NeuroP (8.4 ± 1.7 µg/mL 24 h(-1)) and 10-F4t-NeuroP (5.2 ± 2.9 µg/mL 24 h(-1)) were detected in this group. For the Cg and SLT groups, no significant changes had occurred at the end of the two-week experimental period. Therefore, and as the main conclusion, the training at moderate altitude increased the F4-NeuroPs- and F2-dihomo-isoPs-related oxidative damage of the central nervous system compared to similar training at sea level.


Assuntos
Biomarcadores/urina , F2-Isoprostanos/urina , Neuroprostanos/urina , Estresse Oxidativo/fisiologia , Adulto , Altitude , Atletas , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/fisiologia , Cromatografia Líquida , Exercício Físico , Feminino , Humanos , Masculino , Espectrometria de Massas em Tandem
20.
Nutr Hosp ; 32(2): 799-807, 2015 Aug 01.
Artigo em Espanhol | MEDLINE | ID: mdl-26268114

RESUMO

INTRODUCTION: the triathlon is an endurance sport and individual that consists of three different disciplines: swimming, cycling and running. The aim of the study was to describe and analyze the anthropometric characteristics, body composition and somatotype in male college triathletes. METHODOLOGY: observational and descriptive study of anthropometric characteristics, body composition and somatotype of 39 male college athletes from 24 ± 4,5 years, participants in the championship of Spain university triathlon sprint mode (Alicante 2010), from different universities Spanish. According to anthropometric measurement techniques adopted by the International Society for the Advancement of Kinanthropometry (ISAK) and the Spanish Group Cineantropometría (GREC) by an accredited assessor ISAK Level II. RESULTS: we find athletes of stunting, where you destacanvalores below normal in the subscapularis, supraspinatus, triceps and biceps skinfold, percentage of muscle mass (45.27 ± 3.29%) and fat mass (10.22 ± 2.92%) and bone (16.65 ± 1.34%) and where mesomorphy somatotipo predominates. DISCUSSION: the triathletes and runners have lower size that cyclists and swimmers. Triathletes and cyclists show a similar weight, less than swimmers line, and more than 10km runners. Iliac crest skinfold, abdominal and thigh front cyclists are less than triathletes. The percentage of fat mass of runners triathletes and swimmers are similar, however the muscle mass of athletes usually less than cyclists but similar to other forms. Somatotype resembles triathlete cyclist (mesomorph). The corridor is ectomorph and mesomorph-swimmer can range from a ectomorph mesomorph.


Introducción: el triatlón es un deporte de resistencia e individual que está formado por tres disciplinas diferentes: natación, ciclismo y carrera a pie. El objetivo del estudio es describir las características antropométricas en triatletas varones universitarios, además de analizar y describir la composición corporal y el somatotipo de dichos triatletas. Metodología: estudio observacional y descriptivo de las características antropométricas, la composición corporal y el somatotipo de 39 triatletas varones universitarios entre 24 ± 4,5 años, participantes en el campeonato de España universitario de triatlón, modalidad sprint (Alicante 2010), procedentes de diferentes universidades españolas. Según la técnicas de medición antropométrica adoptadas por la International Society for the Advancement of Kinanthropometry (ISAK) y el Grupo Español de Cineantropometría (GREC) por un evaluador acreditado ISAK de nivel II. Resultados: nos encontramos con deportistas de talla baja, en los que destacan valores inferiores a lo normal en los pliegues cutáneos subescapular, supraespinal, tricipital y bicipital, un porcentaje de masa muscular (45,27 ± 3,29%), de masa grasa (10,22 ± 2,92%) y de masa ósea (16,65 ± 1,34%) y un somatotipo en el que predomina la mesomorfia. Discusión: los triatletas y corredores presentan más baja talla que los ciclistas y nadadores. Los triatletas y ciclistas muestran un peso similar, siendo menor que el de los nadadores de fondo y mayor que el de los corredores de 10 km. Los pliegues cutáneos cresta ilíaca, abdominal y muslo frontal de los ciclistas son inferiores al de los triatletas. El porcentaje de masa grasa de triatletas corredores y nadadores son similares; sin embargo, el de la masa muscular de los triatletas suele ser inferior al de los ciclistas pero similar a las demás modalidades. El somatotipo del triatleta se asemeja al del ciclista (mesomorfo). El del corredor es mesomorfo-ectomorfo y el del nadador puede oscilar de mesomorfo a ectomorfo.


Assuntos
Atletas , Composição Corporal , Somatotipos , Esportes , Tecido Adiposo , Adulto , Antropometria , Osso e Ossos , Humanos , Músculo Esquelético , Espanha , Estudantes , Universidades , Adulto Jovem
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