scholarly journals Time to Exhaustion at the Respiratory Compensation Point in Recreational Cyclists

Author(s):  
Susana Moral-González ◽  
Javier González-Sánchez ◽  
Pedro L. Valenzuela ◽  
Sonia García-Merino ◽  
Carlos Barbado ◽  
...  

The time to exhaustion (tlim) at the respiratory compensation point (RCP) and whether a physiological steady state is observed at this workload remains unknown. Thus, this study analyzed tlim at the power output eliciting the RCP (tlim at RCP), the oxygen uptake (VO2) response to this effort, and the influence of endurance fitness. Sixty male recreational cyclists (peak oxygen uptake [VO2peak] 40–60 mL∙kg∙min−1) performed an incremental test to determine the RCP, VO2peak, and maximal aerobic power (MAP). They also performed constant-load tests to determine the tlim at RCP and tlim at MAP. Participants were divided based on their VO2peak into a low-performance group (LP, n = 30) and a high-performance group (HP, n = 30). The tlim at RCP averaged 20 min 32 s ± 5 min 42 s, with a high between-subject variability (coefficient of variation 28%) but with no differences between groups (p = 0.788, effect size = 0.06). No consistent relationships were found between the tlim at RCP and the different fitness markers analyzed (RCP, power output (PO) at RCP, VO2peak, MAP, or tlim at MAP; all p > 0.05). VO2 remained steady overall during the tlim test, although a VO2 slow component (i.e., an increase in VO2 >200 mL·min−1 from the third min to the end of the tests) was present in 33% and 40% of the participants in HP and LP, respectively. In summary, the PO at RCP could be maintained for about 20 min. However, there was a high between-subject variability in both the tlim and in the VO2 response to this effort that seemed to be independent of fitness level, which raises concerns on the suitability of this test for fitness assessment.

Motricidade ◽  
2018 ◽  
Vol 13 (4) ◽  
pp. 39
Author(s):  
Nuno Almeida ◽  
Joana Reis ◽  
João Beckert ◽  
Miguel Moreira ◽  
Francisco Alves

The purpose of this study was to verify if competitive performance status was associated to different levels of specific aerobic fitness in Portuguese surfboard riders. Six recreational surfers (age: 32.3±3.1 years; body mass: 73.2±7.8kg; height: 1.75±0.05m) and six competitive international level surfers (age: 25±8.4years; body mass: 68.5±3.8kg; height: 1.74±0.05m) performed a maximal continuous incremental paddling test consisting of two-minute steps starting at 20W, with increments of 10W, for determination of peak oxygen uptake and maximal aerobic power. Ventilatory threshold and respiratory compensation point with corresponding heart rate and power output were also determined. Elite surfers presented higher values for peak oxygen uptake (43.6±7.9 ml.kg-1.min-1) than recreational surfers (31.1±7.4 ml.kg-1.min-1, p=0.01) however, there were no differences (p> 0.05) between groups for maximal aerobic power (elite: 76.6±18.6W; recreational: 76.6±16.6W). No significant differences between the power output at which ventilatory threshold or respiratory compensation point occurred but elite surfers reached ventilation threshold with 22.5±5.8 ml.kg-1.min-1 which was significantly higher than recreational surfers (16±3.7 ml.kg-1.min-1). These findings show that elite surfers have higher values of peak oxygen uptake than recreational surfers which suggest a higher aerobic adaptation that may be related to the different amount of exercise volume undertaken.


2020 ◽  
Vol 15 (7) ◽  
pp. 1047-1051
Author(s):  
David Barranco-Gil ◽  
Jaime Gil-Cabrera ◽  
Pedro L. Valenzuela ◽  
Lidia B. Alejo ◽  
Almudena Montalvo-Pérez ◽  
...  

Purpose: The functional threshold power (FTP), which demarcates the transition from steady state to non-steady-state oxidative metabolism, is usually determined with a 20-minute cycling time trial that follows a standard ∼45-minute warm-up. This study aimed to determine if the standard warm-up inherent to FTP determination is actually necessary and how its modification or removal affects the relationship between FTP and the respiratory compensation point (RCP). Methods: A total of 15 male cyclists (age 35 [9] y, maximum oxygen uptake 66.4 [6.8] mL·kg−1·min−1) participated in this randomized, crossover study. Participants performed a ramp test for determination of RCP and maximum oxygen uptake. During subsequent visits, they performed a 20-minute time trial preceded by the “standard” warm-up that is typically performed before an FTP test (S-WU), a 10-minute warm-up at the power output (PO) corresponding to 60% of maximum oxygen uptake (60%-WU), or no warm-up (No-WU). FTP was computed as 95% of the mean PO attained during the time trial. Results: Although the FTP was correlated with the RCP independently of the warm-up (r = .89, .93, and .86 for No-WU, 60%-WU, and S-WU, respectively; all Ps < .001), the PO at RCP was higher than the FTP in all cases (bias ± 95% limits of agreement = 57 [24], 60 [23], and 57 [32] W for No-WU, 60%-WU, and S-WU, respectively; all Ps < .001 and effect size > 1.70). Conclusions: The FTP is highly correlated with the RCP but corresponds to a significantly lower PO, being these results independent of the warm-up performed (or even with no warm-up).


2017 ◽  
Vol 12 (10) ◽  
pp. 1363-1369 ◽  
Author(s):  
Tatiane Piucco ◽  
Fernando Diefenthaeler ◽  
Rogério Soares ◽  
Juan M. Murias ◽  
Guillaume Y. Millet

Purpose: To investigate the criterion validity of a maximal incremental skating test performed on a slide board (SB). Methods: Twelve subelite speed skaters performed a maximal skating test on a treadmill and on a SB. Gas exchange threshold (GET), respiratory compensation point (RCP), and maximal variables were determined. Results: Oxygen uptake () (31.0 ± 3.2 and 31.4 ± 4.1 mL·min−1·kg−1), percentage of maximal () (66.3 ± 4 and 67.7 ± 7.1%), HR (153 ± 14 and 150 ±12 bpm), and ventilation (59.8 ± 11.8 and 57.0 ± 10.7 L·min−1) at GET, and (42.5 ± 4.4 and 42.9 ± 4.8 mL·min−1·kg−1), percentage of (91.1 ± 3.3 and 92.4 ± 2.1%), heart rate (HR) (178 ± 9 and 178 ± 6 bpm), and ventilation (96.5 ± 19.2 and 92.1 ± 12.7 L·min−1) at RCP were not different between skating on a treadmill and on a SB. (46.7 ± 4.4 vs 46.4 ±6.1 mL·min−1·kg−1) and maximal HR (195 ± 6 vs 196 ± 10 bpm) were not significantly different and correlated (r = .80 and r = .87, respectively; P < .05) between the treadmill and SB. at GET, RCP, and obtained on a SB were correlated (r > .8) with athletes’ best times on 1500 m. Conclusions: The incremental skating test on a SB was capable to distinguish maximal ( and HR) and submaximal (, % , HR, and ventilation) parameters known to determine endurance performance. Therefore, the SB test can be considered as a specific and practical alternative to evaluate speed skaters.


2015 ◽  
Vol 10 (5) ◽  
pp. 636-641 ◽  
Author(s):  
Michelle S.M. Silva ◽  
Wladimir Bolani ◽  
Cleber R. Alves ◽  
Diogo G. Biagi ◽  
José R. Lemos ◽  
...  

Aim:To study the relationship between the ACTN3 R577X polymorphism and oxygen uptake (VO2) before and after exercise training.Methods:Police recruits (N = 206, 25 ± 4 y) with RR (n = 75), RX (n = 97), and XX (n = 33) genotypes were selected. After baseline measures, they underwent 18 wk of running endurance training. Peak VO2 was obtained by cardiopulmonary exercise testing.Results:Baseline body weight was not different among genotypes. At baseline, XX individuals displayed higher VO2 at anaerobic threshold, respiratory compensation point, and exercise peak than did RR individuals (P < .003). Endurance training significantly increased VO2 at anaerobic threshold, respiratory compensation point, and exercise peak (P < 2 × 10−6), but the differences between XX and RR were no longer observed. Only relative peak VO2 exercise remained higher in XX than in RR genotype (P = .04). In contrast, the increase in relative peak VO2 was greater in RR than in XX individuals (12% vs 6%; P = .02).Conclusion:ACTN3 R577X polymorphism is associated with VO2. XX individuals have greater aerobic capacity. Endurance training eliminates differences in peak VO2 between XX and RR individuals. These findings suggest a ceiling-effect phenomenon, and, perhaps, trained individuals may not constitute an adequate population to explain associations between phenotypic variability and gene variations.


Author(s):  
Murillo Frazão ◽  
Paulo Eugênio Silva ◽  
Lucas de Assis Pereira Cacau ◽  
Tullio Rocha Petrucci ◽  
Mariela Cometki Assis ◽  
...  

Author(s):  
William J.M. Kinnear ◽  
James H. Hull

This chapter describes how acidaemia stimulates ventilation in the later stages of a cardiopulmonary exercise test (CPET). This happens after the anaerobic threshold, once the capacity of the blood to buffer lactic acid has been used up. The respiratory compensation point (RCP) can be identified from an increase in the slope when minute ventilation (VE) is plotted against carbon dioxide output (VCO2), or from a rise in the ventilatory equivalents for carbon dioxide (VeqCO2). The presence of a clear RCP indicates that the subject has made a fairly maximal effort during the CPET. An RCP also argues against significant lung disease, since it implies the ability to increase ventilation in response to acidaemia.


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