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1.
Int J Sports Med ; 43(7): 600-607, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33017851

RESUMO

The study aimed to assess the relationship between peak oxygen uptake, ventilatory thresholds and maximal fat oxidation with ultra trail male and female performance. 47 athletes (29 men and 18 women) completed a cardiopulmonary exercise test between 2 to 4 weeks before a 107-km ultra trail. Body composition was also analyzed using a bioelectrical impedance weight scale. Exploratory correlation analyses showed that peak oxygen uptake (men: r=-0.63, p=0.004; women: r=-0.85, p < 0.001), peak speed (men: r=-0.74, p < 0.001; women: r=-0.69, p=0.009), speed at first (men: r=-0.49, p=0.035; women: r=-0.76, p=0.003) and second (men: r=-0.73, p < 0.001; women: r=-0.76, p=0.003) ventilatory threshold, and maximal fat oxidation (men: r=-0.53, p=0.019; women: r=-0.59, p=0.033) were linked to race time in male and female athletes. Percentage of fat mass (men: r=0.58, p=0.010; women: r=0.62, p= 0.024) and lean body mass (men: r=-0.61, p=0.006; women: r=-0.61, p=0.026) were also associated with performance in both sexes. Subsequent multiple regression analyses revealed that peak speed and maximal fat oxidation together were able to predict 66% of male performance; while peak oxygen uptake was the only statistically significant variable explaining 69% of the variation in women's race time. These results, although exploratory in nature, suggest that ultra trail performance is differently predicted by endurance variables in men and women.


Assuntos
Consumo de Oxigênio , Resistência Física , Atletas , Teste de Esforço , Feminino , Humanos , Masculino , Oxigênio
2.
J Strength Cond Res ; 36(6): 1629-1635, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32796418

RESUMO

ABSTRACT: Martínez-Navarro, I, Montoya-Vieco, A, Collado, E, Hernando, B, Panizo, N, and Hernando, C. Muscle Cramping in the marathon: Dehydration and electrolyte depletion vs. muscle damage. J Strength Cond Res 36(6): 1629-1635, 2022-Our aim was to compare dehydration variables, serum electrolytes, and muscle damage serum markers between runners who suffered exercise-associated muscle cramps (EAMC) and runners who did not suffer EAMC in a road marathon. We were also interested in analyzing race pacing and training background. Nighty-eight marathoners took part in the study. Subjects were subjected to a cardiopulmonary exercise test. Before and after the race, blood and urine samples were collected and body mass (BM) was measured. Immediately after the race EAMC were diagnosed. Eighty-eight runners finished the marathon, and 20 of them developed EAMC (24%) during or immediately after the race. Body mass change, post-race urine specific gravity, and serum sodium and potassium concentrations were not different between crampers and noncrampers. Conversely, runners who suffered EAMC exhibited significantly greater post-race creatine kinase (464.17 ± 220.47 vs. 383.04 ± 253.41 UI/L, p = 0.034) and lactate dehydrogenase (LDH) (362.27 ± 72.10 vs. 307.87 ± 52.42 UI/L, p = 0.002). Twenty-four hours post-race also values of both biomarkers were higher among crampers (CK: 2,438.59 ± 2,625.24 vs. 1,166.66 ± 910.71 UI/L, p = 0.014; LDH: 277.05 ± 89.74 vs. 227.07 ± 37.15 UI/L, p = 0.021). The difference in the percentage of runners who included strength conditioning in their race training approached statistical significance (EAMC: 25%, non-EAMC: 47.6%; p = 0.074). Eventually, relative speed between crampers and noncrampers only differed from the 25th km onward (p < 0.05). Therefore, runners who suffered EAMC did not exhibit a greater degree of dehydration and electrolyte depletion after the marathon but displayed significantly higher concentrations of muscle damage biomarkers.


Assuntos
Corrida de Maratona , Cãibra Muscular , Biomarcadores , Creatina Quinase , Desidratação , Eletrólitos , Humanos , Cãibra Muscular/etiologia , Músculos
3.
J Hum Kinet ; 80: 71-82, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34868418

RESUMO

The study was aimed at comparing pacing adopted by males and females in a 107-km mountain ultramarathon and assessing whether pacing-related variables were associated with intracompetition body weight changes and performance. Forty-seven athletes (29 males; 18 females) were submitted to a cardiopulmonary exercise test before the race. Athletes were also weighted before the start of the race, at three midpoints (33 km, 66 km and 84 km) and after the race. Pacing was analyzed using absolute and relative speeds and accelerometry-derived sedentary time spent during the race. Results showed that females spent less sedentary time (4.72 ± 2.91 vs. 2.62 ± 2.14%; p = 0.035; d = 0.83) and displayed a smaller body weight loss (3.01 ± 1.96 vs. 4.37 ± 1.77%; p = 0.048; d = 0.77) than males. No significant sex differences were revealed for speed variability, absolute and relative speed. In addition, finishing time was correlated with: speed variability (r = 0.45; p = 0.010), index of pacing (r = -0.63; p < 0.001) and sedentary time (r = 0.64; p < 0.001). Meanwhile, intracompetition body weight changes were related with both the absolute and relative speed in the first and the last race section. These results suggest that females, as compared with males, take advantage of shorter time breaks at aid stations. Moreover, performing a more even pacing pattern may be positively associated with performance in mountain ultramarathons. Finally, intracompetition body weight changes in those races should be considered in conjunction with running speed fluctuations.

4.
Sports (Basel) ; 8(10)2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33066606

RESUMO

The study was aimed at comparing lower-limb strength and respiratory parameters between male and female athletes and their interaction with performance in a 107 km mountain ultramarathon. Forty seven runners (29 males and 18 females; mean ± SD age: 41 ± 5 years) were enrolled. Lower-limb strength assessment comprised a squat jump test, an ankle rebound test, and an isometric strength test. Respiratory assessment included pulmonary function testing and the measurement of maximal inspiratory pressure. Male athletes performed largely better in the squat jump (26 ± 4 vs. 21 ± 3 cm; p < 0.001; d = 1.48), while no sex differences were found in the other two lower-limb tests. Concerning the respiratory parameters, male athletes showed largely greater values in pulmonary expiratory variables: forced vital capacity (5.19 ± 0.68 vs. 3.65 ± 0.52 L; p < 0.001; d = 2.53), forced expiratory volume in 1 s (4.24 ± 0.54 vs. 2.97 ± 0.39 L; p < 0.001; d = 2.69), peak expiratory flow (9.9 ± 1.56 vs. 5.89 ± 1.39 L/min; p < 0.001; d = 2.77) and maximum voluntary ventilation in 12 s (171 ± 39 vs. 108 ± 23 L/min; p < 0.001; d = 1.93); while no sex differences were identified in maximal inspiratory pressure. Race time was associated with ankle rebound test performance (r = -0.390; p = 0.027), isometric strength test performance (r = -0.349; p = 0.049) and maximal inspiratory pressure (r = -0.544; p < 0.001). Consequently, it seems that athletes competing in mountain ultramarathons may benefit from improving lower-limb isometric strength, ankle reactive strength and inspiratory muscle strength. Nevertheless, further interventional studies are required to confirm these exploratory results. In addition, the fact that the magnitude of the sex difference for isometric strength was minor, as compared with the other strength tests, could represent one of the factors explaining why the performance gap between males and females is reduced in ultramarathons.

5.
J Strength Cond Res ; 27(9): 2405-13, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23249821

RESUMO

Little is known about the influence of speed endurance workouts on the improvement of pacing strategies in the 800-m running event. This study aims to analyze it, comparing continuous repetitions vs. interval training workouts. Because we hypothesize that pacing is susceptible to expertise, there might be age differences. Nineteen male 800-m runners (age: 21.36 ± 5.26, season best [SB]: 117.14 ± 5.18 seconds) were tested. Athletes were asked to run 1 × 600 m (6r) at 100% (SB) and 2 × 4 (200 m per 30 seconds) per 15 minutes (B8) at 102% (SB), counterbalanced and randomized within 1 week of difference. Pacing strategy (velocity dynamics) was analyzed by means of time differences in 200-m segments (T200), whereas age category was considered a grouping factor (younger than 23 years-senior, n = 10; vs. juvenile-junior, n = 9; 25.29 ± 4.32, 17.00 ± 0.66 years). Blood lactate was registered after 6r, B(8)1, and B(8)2 bouts. Univariate contrast analysis revealed a significant decrease in velocity during 6r (p < 0.001; 9.33% between first and third segment), thus a positive pacing, whatever the age category. B8 shared this final significant impairment (p < 0.001), although it was smaller (5.73% drop for B(8)1; 8.47% for B(8)2), and neither linear nor significant among consecutive T200. B8 also showed significant differences (p < 0.05) in the interaction sampling condition × age category. The T test added blood lactate significant differences (B(8)2: 15.42 ± 1.16, B(8)1: 12.25 ± 2.03 and 6r: 13.58 ± 1.82 mmol·L(-1)). Summarizing, both methods share a positive pacing, confirming to be related to enhancing energy systems and coping final fatigue in the 800 m. Continuous 6r preserves the nature and tempo of the 800 m, although 1 repetition is metabolically limited. Interval B8 allows larger amounts of high intensity running, enhancing neuromuscular benefits jointly with higher lactate productions. Significant age category differences in B8 indicate that pacing capacity may improve with expertise and interval workouts may be appropriate methods to manage it.


Assuntos
Corrida/fisiologia , Fatores Etários , Desempenho Atlético/fisiologia , Humanos , Lactatos/sangue , Masculino , Educação Física e Treinamento/métodos , Corrida/educação , Adulto Jovem
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