scholarly journals Relationships between acute race-induced changes in creatine kinase activity and blood plasma myoglobin concentration and race performance in mountain bike and road cyclists

2021 ◽  
Author(s):  
Paulina Hebisz ◽  
Jacek Borkowski ◽  
Rafal Hebisz
Keyword(s):  
Creatine Kinase ◽  
Oxygen Uptake ◽  
Power Output ◽  
Maximal Oxygen Uptake ◽  
Aerobic Power ◽  
Ventilatory Threshold ◽  
Maximal Aerobic Power ◽  
Mountain Bike ◽  
Road Cyclists ◽  
Race Performance

The aim of this study was to determine if the changes in plasma creatine kinase (CK) activity and myoglobin (MB) concentrations as markers of muscle damage differ between competitive road (n = 14) and mountain bike (n = 11) cyclists and if these biochemical markers show a relationship with real-world race performance. CK and MB were measured from blood samples collected 2 hours before race start and 1 hour after race completion and the change in pre- and post-race difference was calculated (ΔCK and ΔMB). An incremental exercise test was used to determine maximal oxygen uptake, maximal aerobic power, and power output at the second ventilatory threshold. Post-race CK and MB increased in the whole group of cyclists. Although the magnitude of change in CK was similar in both road and mountain bike cyclists, only the increase in road cyclists was significant. MB significantly increased only in mountain bike cyclists. Multiple regression analysis revealed a significant association between both road and mountain bike race performance and ΔCK and ΔMB. The other significant predictors for mountain bike race performance were maximal aerobic power (W?kg-1) and power output at the second ventilatory threshold (W?kg-1) and for road race performance both maximal oxygen uptake (l?min-1) and power output at the second ventilatory threshold (W). In conclusion, mountain bike racing was associated with an increase in MB whereas road racing with an increase in CK, with the post-race changes in CK and MB related to race performance as high ΔCK and low ΔMB were obtained by better-performing cyclists.

Power Output and Pacing During International Cross-Country Mountain Bike Cycling

2018 ◽  
Vol 13 (9) ◽  
pp. 1243-1249 ◽  
Author(s):  
Cyril Granier ◽  
Chris R. Abbiss ◽  
Anaël Aubry ◽  
Yvon Vauchez ◽  
Sylvain Dorel ◽  
...  
Keyword(s):  
Power Output ◽  
Aerobic Power ◽  
Maximal Aerobic Power ◽  
Mass Ratio ◽  
Mountain Bike ◽  
Fast Start ◽  
World Class ◽  
Physiological Profiles ◽  
Road Cyclists ◽  
Cross Country

Purpose: To characterize the physiological profiles of elite cross-country mountain-bike (XCO-MTB) cyclists and to examine their pacing and power-output (PO) distribution during international races. Methods: Over 2 competitive seasons, 8 male XCO-MTB cyclists (VO2max 79.9 [5.2] mL·min−1·kg−1, maximal aerobic power [MAP] 411 [18] W and 6.3 [0.4] W·kg−1) regularly undertook incremental tests to assess their PO and heart rate (HR) at first and second ventilatory thresholds (VT1 and VT2) and at VO2max. During the same period, their PO, HR, speed, and cadence were recorded over 13 international races (total of 30 recorded files). Results: Mean PO, speed, cadence, and HR during the races were 283 (22) W (4.31 [0.32] W·kg−1, 68% [5%] MAP), 19.7 (2.1) km·h−1, 68 (8) rpm, and 172 (11) beats·min−1 (91% [2%] HRmax), respectively. The average times spent below 10% of MAP, between 10% of MAP and VT1, between VT1 and VT2, between VT2 and MAP, and above MAP were 25% (5%), 21% (4%), 13% (3%), 16% (3%), and 26% (5%), respectively. Both speed and PO decreased from the start loop to lap 1 before stabilizing until the end of the race.Conclusions: Elite off-road cyclists demonstrated typical values of world-class endurance cyclists with an excellent power-to-mass ratio. This study demonstrated that XCO-MTB races are performed at higher intensities than reported in previous research and are characterized by a fast start followed by an even pace.

Eighteen days of “living high, training low” stimulate erythropoiesis and enhance aerobic performance in elite middle-distance runners

2006 ◽  
Vol 100 (1) ◽  
pp. 203-211 ◽  
Author(s):  
Julien V. Brugniaux ◽  
Laurent Schmitt ◽  
Paul Robach ◽  
Gérard Nicolet ◽  
Jean-Pierre Fouillot ◽  
...  
Keyword(s):  
Oxygen Uptake ◽  
Maximal Oxygen Uptake ◽  
Aerobic Power ◽  
Ventilatory Threshold ◽  
Maximal Aerobic Power ◽  
Aerobic Performance ◽  
Control Group ◽  
Distance Runners ◽  
Early Return ◽  
Oxygen Carrying Capacity

The efficiency of “living high, training low” (LHTL) remains controversial, despite its wide utilization. This study aimed to verify whether maximal and/or submaximal aerobic performance were modified by LHTL and whether these effects persist for 15 days after returning to normoxia. Last, we tried to elucidate whether the mechanisms involved were only related to changes in oxygen-carrying capacity. Eleven elite middle-distance runners were tested before (Pre), at the end (Post1), and 15 days after the end (Post2) of an 18-day LHTL session. Hypoxic group (LHTL, n = 5) spent 14 h/day in hypoxia (6 nights at 2,500 m and 12 nights at 3,000 m), whereas the control group (CON, n = 6) slept in normoxia (1,200 m). Both LHTL and CON trained at 1,200 m. Maximal oxygen uptake and maximal aerobic power were improved at Post1 and Post2 for LHTL only (+7.1 and +3.4% for maximal oxygen uptake, +8.4 and +4.7% for maximal aerobic power, respectively). Similarly oxygen uptake and ventilation at ventilatory threshold increased in LHTL only (+18.1 and +12.2% at Post1, +15.9 and +15.4% at Post2, respectively). Heart rate during a 10-min run at 19.5 km/h decreased for LHTL at Post2 (−4.4%). Despite the stimulation of erythropoiesis in LHTL shown by the 27.4% increase in serum transferrin receptor and the 10.1% increase in total hemoglobin mass, red cell volume was not significantly increased at Post1 (+9.2%, not significant). Therefore, both maximal and submaximal aerobic performance in elite runners were increased by LHTL mainly linked to an improvement in oxygen transport in early return to normoxia and probably to other process at Post2.

scholarly journals PPeak oxygen uptake differentiates competitive from recreational male surfboard riders

Motricidade ◽  
2018 ◽  
Vol 13 (4) ◽  
pp. 39
Author(s):  
Nuno Almeida ◽  
Joana Reis ◽  
João Beckert ◽  
Miguel Moreira ◽  
Francisco Alves
Keyword(s):  
Oxygen Uptake ◽  
Body Mass ◽  
Power Output ◽  
Aerobic Power ◽  
Ventilatory Threshold ◽  
Peak Oxygen Uptake ◽  
Maximal Aerobic Power ◽  
Compensation Point ◽  
Respiratory Compensation Point ◽  
Respiratory Compensation

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.

Physiological and Mechanical Indices Serving the New Cross-Country Olympic Mountain Bike Performance

2020 ◽  
pp. 1-6
Author(s):  
Arnaud Hays ◽  
Caroline Nicol ◽  
Denis Bertin ◽  
Romain Hardouin ◽  
Jeanick Brisswalter
Keyword(s):  
Power Output ◽  
Aerobic Power ◽  
Multiple Regression Model ◽  
Maximal Aerobic Power ◽  
Maximum Power ◽  
Active Recovery ◽  
Mountain Bike ◽  
Testing Protocol ◽  
Cross Country ◽  
Aerobic Power Output

Objectives: To identify relevant physiological, mechanical, and strength indices to improve the evaluation of elite mountain bike riders competing in the current Cross-Country Olympic (XCO) format. Methods: Considering the evolution of the XCO race format over the last decade, the present testing protocol adopted a battery of complementary laboratory cycling tests: a maximal aerobic consumption, a force–velocity test, and a multi-short-sprint test. A group of 33 elite-level XCO riders completed the entire testing protocol and at least 5 international competitions. Results: Very large correlations were found between the XCO performance and maximal aerobic power output (r = .78; P < .05), power at the second ventilation threshold (r = .83; P < .05), maximal pedaling force (r = .77; P < .05), and maximum power in the sixth sprint (r = .87; P < .05) of the multi-short-sprint test. A multiple regression model revealed that the normalized XCO performance was predicted at 89.2% (F3,29 = 89.507; r = .95; P < .001) by maximum power in the sixth sprint (β = 0.602; P < .001), maximal pedaling rate (β = 0.309; P < .001), and relative maximal aerobic power output (β = 0.329; P < .001). Discussion: Confirming our expectations, the current XCO performance was highly correlated with a series of physiological and mechanical parameters reflecting the high level of acyclic and intermittent solicitation of both aerobic and anaerobic metabolic pathways and the required qualities of maximal force and velocity. Conclusion: The combination of physiological, mechanical, and strength characteristics may thus improve the prediction of elite XCO cyclists’ performance. It seems of interest to evaluate the ability to repeatedly produce brief intensive efforts with short active recovery periods.

Maximal oxygen uptake, ventilatory threshold and fat oxidation after an incremental exercise test in triathletes

2017 ◽  
Vol 176 (12) ◽  
Author(s):  
Hanapi M. Johari ◽  
Brinnell A. Caszo ◽  
Victor F. Knight ◽  
Steven A. Lumley ◽  
Aminuddin K. Abdul Hamid ◽  
...  
Keyword(s):  
Oxygen Uptake ◽  
Exercise Test ◽  
Maximal Oxygen Uptake ◽  
Ventilatory Threshold ◽  
Fat Oxidation ◽  
Incremental Exercise ◽  
Incremental Exercise Test

Does Cerebral Blood Flow Limit Maximal Aerobic Power Output?

2011 ◽  
Vol 43 (Suppl 1) ◽  
pp. 82
Author(s):  
Andrew W. Subudhi ◽  
J Tod Olin ◽  
Andrew C. Dimmen ◽  
Bengt Kayser ◽  
Robert C. Roach
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Power Output ◽  
Aerobic Power ◽  
Maximal Aerobic Power ◽  
Flow Limit ◽  
Aerobic Power Output

scholarly journals The Validity of Functional Threshold Power and Maximal Oxygen Uptake for Cycling Performance in Moderately Trained Cyclists

Sports ◽  
2019 ◽  
Vol 7 (10) ◽  
pp. 217 ◽  
Author(s):  
Arne Sørensen ◽  
Tore Kristian Aune ◽  
Vegar Rangul ◽  
Terje Dalen
Keyword(s):  
Oxygen Uptake ◽  
Maximal Oxygen Uptake ◽  
Local Level ◽  
Cycling Performance ◽  
Threshold Power ◽  
Mountain Bike ◽  
Mean Power ◽  
Valid Test ◽  
The Mean ◽  
And Performance

Cycling is a popular sport, and evaluation of the validity of tests to predict performance in competitions is important for athletes and coaches. Similarity between performance in sprints in mass-start bike races and in the laboratory is found, but, to our knowledge, no studies have investigated the relationship between laboratory measurements of maximal oxygen uptake (VO2max) and functional threshold power (FTP) with performance in official mass-start competitions. The purpose of this study was to evaluate the validity of a 20 min FTP test and VO2max as predictors for performance in an official mountain bike competition. Eleven moderately trained male cyclists at a local level participated in this study (age: 43 ± 5.1 years; height: 183.4 ± 5.4 m; weight: 84.4 ± 8.7 kg; body mass index: 25.1 ± 2.1). All subjects performed a 20 min FTP test in the laboratory to measure the mean power. In addition, the subjects completed an incremental test to exhaustion to determine VO2max. These two laboratory tests were analyzed together with the results from a 47 km mass-start mountain bike race, with a total elevation of 851 m. A significant relationship was found between the mean relative power (W/kg) for the 20 min FTP test and performance time in the race (r = −0.74, P < 0.01). No significant correlation was found between VO2max and cycling performance for these subjects (r = −0.37). These findings indicate that a 20 min FTP test is a more valid test for prediction of performance in mass-start bike races than a VO2max test for moderately trained cyclists.

scholarly journals Metabolic consequences of β-alanine supplementation during exhaustive supramaximal cycling and 4000-m time-trial performance

2016 ◽  
Vol 41 (8) ◽  
pp. 864-871 ◽  
Author(s):  
Phillip M. Bellinger ◽  
Clare L. Minahan
Keyword(s):  
Oxygen Uptake ◽  
Power Output ◽  
Maximal Oxygen Uptake ◽  
Anaerobic Power ◽  
Anaerobic Capacity ◽  
Time Trial ◽  
Time To Exhaustion ◽  
Cycling Test ◽  
Cycling Time Trial ◽  
Aerobic And Anaerobic

The present study investigated the effects of β-alanine supplementation on the resultant blood acidosis, lactate accumulation, and energy provision during supramaximal-intensity cycling, as well as the aerobic and anaerobic contribution to power output during a 4000-m cycling time trial (TT). Seventeen trained cyclists (maximal oxygen uptake = 4.47 ± 0.55 L·min−1) were administered 6.4 g of β-alanine (n = 9) or placebo (n = 8) daily for 4 weeks. Participants performed a supramaximal cycling test to exhaustion (equivalent to 120% maximal oxygen uptake) before (PreExh) and after (PostExh) the 4-week supplementation period, as well as an additional postsupplementation supramaximal cycling test identical in duration and power output to PreExh (PostMatch). Anaerobic capacity was quantified and blood pH, lactate, and bicarbonate concentrations were measured pre-, immediately post-, and 5 min postexercise. Subjects also performed a 4000-m cycling TT before and after supplementation while the aerobic and anaerobic contributions to power output were quantified. β-Alanine supplementation increased time to exhaustion (+12.8 ± 8.2 s; P = 0.041) and anaerobic capacity (+1.1 ± 0.7 kJ; P = 0.048) in PostExh compared with PreExh. Performance time in the 4000-m TT was reduced following β-alanine supplementation (−6.3 ± 4.6 s; P = 0.034) and the mean anaerobic power output was likely to be greater (+6.2 ± 4.5 W; P = 0.035). β-Alanine supplementation increased time to exhaustion concomitant with an augmented anaerobic capacity during supramaximal intensity cycling, which was also mirrored by a meaningful increase in the anaerobic contribution to power output during a 4000-m cycling TT, resulting in an enhanced overall performance.

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