Effect Of Acute Passive Stretching On Maximum Aerobic Power And Time To Exhaustion

Previous studies had indicated that maximum aerobic power (VO2 max) would be seriously impaired when HbCO levels were above 7% but was not altered if HbCO was around 2.7%. The present studies indicated that the critical level at which HbCO influenced VO2 max was approximately 4.3%. This was accompanied as in the above-noted studied with a reduction in total work time to the attainment of VO2 max. Two procedures to raise HbCO to appropriate levels were employed, i.e., a buildup wherin HbCO was incrementally increased by breathing ambient air containing 75 or 100 ppm CO and a bolus plus maintenance procedure. In the latter, HbCO was raised to the level attained in the buildup test by giving a “bolus” of CO followed by the continued inhalation of CO at a level to just maintain this level of HbCO regardless of the magnitude of the ventilation. Regardless of the mode of presentation, the decrement in VO2 max occurred at the same level of HbCO. These observations are of considerable significance, since it indicated that even low ambient levels of CO (23.7 ppm) would result in lowering maximum aerobic power if the individual had been previously exposed to CO such that the level was raised to this critical point.

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Maximum aerobic power and body composition during the puberty growth period: Similarities and differences between children of two European countries

European Journal of Pediatrics ◽

10.1007/bf00441914 ◽

1981 ◽

Vol 136 (2) ◽

pp. 123-133 ◽

Cited By ~ 37

Author(s):

J. Rutenfranz ◽

K. Lange Andersen ◽

V. Seliger ◽

F. Klimmer ◽

I. Berndt ◽

...

Keyword(s):

Body Composition ◽

Aerobic Power ◽

Growth Period ◽

European Countries ◽

Maximum Aerobic Power ◽

Similarities And Differences

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The Astrand-Ryhming nomogram revisited

Journal of Applied Physiology ◽

10.1152/jappl.1986.61.3.1203 ◽

1986 ◽

Vol 61 (3) ◽

pp. 1203-1209 ◽

Cited By ~ 38

Author(s):

B. J. Legge ◽

E. W. Banister

Keyword(s):

Heart Rate ◽

Aerobic Power ◽

Constant Load ◽

Cycle Ergometry ◽

Gas Analysis ◽

Work Rate ◽

Exercise Heart Rate ◽

Validation Group ◽

O2 Uptake ◽

Maximum Aerobic Power

Relationships among O2 uptake (VO2), heart rate, and work rate during constant-load submaximal cycle ergometry and ramp-forced exercise to exhaustion have been studied in core groups of trained (n = 15) and untrained (n = 10), 20- to 29-yr-old males. A signal aim was to improve on the accuracy of the 1954 Astrand-Ryhming (A-R) nomogram predicting maximum aerobic power from heart rate elevation at submaximum work rates. A new nomogram has been developed based on a linear relationship, established in experimental groups, between VO2 and delta HR, the latter being defined as the elevation of exercise heart rate above that reached during zero-load pedaling at 90 rpm. The delta HR variable used in a nomogram linking it and submaximum VO2 (either derived by calculation from the concomitant steady-state work rate or measured directly from respiratory gas analysis) successfully differentiated maximum aerobic power of trained from untrained subjects in core groups whose different abilities could not otherwise be distinguished by the A-R nomogram itself. In a validation group of trained (n = 5), untrained (n = 5), and moderately trained (n = 4) 20- to 29-yr-old males, the correlation measured between VO2max values and those predicted from the new nomogram was significantly better (r = 0.98) (P less than 0.05) than predictions made from the A-R nomogram (r = 0.80).

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Magnesium and vitamin B2 supplementation is an important nutritional resource of sports medicine

Medical Council ◽

10.21518/2079-701x-2018-21-216-230 ◽

2019 ◽

pp. 216-230

Author(s):

O. A. Gromova ◽

I. Yu. Torshin ◽

M. A. Sorokina ◽

A. N. Gromov

Keyword(s):

Energy Metabolism ◽

Aqueous Solutions ◽

Sports Medicine ◽

Cardiovascular Health ◽

Aerobic Power ◽

Vitamin B2 ◽

Magnesium Citrate ◽

Intensive Training ◽

Maximum Aerobic Power ◽

Hormonal Balance

The supply of the with magnesium and vitamin B2 is essential to maintain the energy metabolism of cells, hormonal balance, endurance, immunity, cardiovascular health of athletes. As a result, by increasing the availability of these micronutrients, it is possible to increase maximum aerobic power, achieve better sports results and stimulate adequate recovery after competition or after intensive training. A promising way to increase the supply of athletes with magnesium and vitamin B2 is the use of aqueous solutions of magnesium citrate in combination with riboflavin.

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Ischemic Preconditioning: Improved Cycling Performance Despite Nocebo Expectation

International Journal of Sports Physiology and Performance ◽

10.1123/ijspp.2019-0290 ◽

2020 ◽

Vol 15 (3) ◽

pp. 354-360 ◽

Cited By ~ 1

Author(s):

Christian P. Cheung ◽

Joshua T. Slysz ◽

Jamie F. Burr

Keyword(s):

Ischemic Preconditioning ◽

Aerobic Power ◽

Lactate Concentration ◽

Cycling Performance ◽

Cycle Ergometer ◽

Time To Exhaustion ◽

Performance Expectations ◽

Sham Treatment ◽

Positive Expectation ◽

Placebo Controls

Purpose: Ischemic preconditioning (IPC) through purposeful circulatory occlusion may enhance exercise performance. The value of IPC for improving performance is controversial owing to challenges with employing effective placebo controls. This study examines the efficacy of IPC versus a deceptive sham protocol for improving performance to determine whether benefits of IPC are attributable to true physiological effects. It was hypothesized that IPC would favorably alter performance more than a sham treatment and that physiological responses to exercise would be affected only after IPC treatment. Methods: In a randomized order, 16 participants performed incremental exercise to exhaustion on a cycle ergometer in control conditions and after sham and IPC treatments. Participants rated their belief as to the efficacy of each treatment compared with control. Results: Time to exhaustion was greatest after IPC (control = 1331 [270] s, IPC = 1429 [300] s, sham = 1343 [255] s, P = .02), despite negative performance expectations after IPC and positive expectation after sham. Maximal aerobic power remained unchanged after both SHAM and IPC (control = 42.0 [5.2], IPC = 41.7 [5.5], sham = 41.6 [5.5] mL·kg−1·min−1, P = .7), as did submaximal lactate concentration (control = 8.9 [2.6], sham = 8.0 [1.9], IPC = 7.7 [2.1] mmol, P = .1) and oxygen uptake (control = 37.8 [4.8], sham = 37.5 [5.3], IPC = 37.5 [5.5] mL·kg−1·min−1, P = .6). Conclusions: IPC before cycling exercise provides an ergogenic benefit that is not attributable to a placebo effect from positive expectation and that was not explained by traditionally suggested mechanisms.

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Time to Exhaustion at the VO2max Velocity in Swimming: A Review

Journal of Human Kinetics ◽

10.2478/v10078-012-0029-1 ◽

2012 ◽

Vol 32 (1) ◽

pp. 121-134 ◽

Cited By ~ 16

Author(s):

Ricardo Fernandes ◽

J. Vilas-Boas

Keyword(s):

Anaerobic Threshold ◽

Direct Relationship ◽

Aerobic Power ◽

Slow Component ◽

Lactate Production ◽

Inverse Correlation ◽

Time To Exhaustion ◽

Swimming Velocity ◽

Stroke Index ◽

Stroke Length

Time to Exhaustion at the VO2max Velocity in Swimming: A Review The aim of this study was to present a review on the time to exhaustion at the minimum swimming velocity corresponding to maximal oxygen consumption (TLim-vVO2max). This parameter is critical both for the aerobic power and the lactate tolerance bioenergetical training intensity zones, being fundamental to characterize it, and to point out its main determinants. The few number of studies conducted in this topic observed that swimmers were able to maintain an exercise intensity corresponding to maximal aerobic power during 215 to 260 s (elite swimmers), 230 to 260 s (high level swimmers) and 310 to 325 s (low level swimmers), and no differences between genders were reported. TLim-vVO2max main bioenergetic and functional determinants were swimming economy and VO2 slow component (direct relationship), and vVO2max, velocity at anaerobic threshold and blood lactate production (inverse relationship); when more homogeneous groups of swimmers were analysed, the inverse correlation value between TLim-vVO2max and vVO2max was not so evident. In general, TLim-vVO2max was not related to VO2max. TLim-vVO2max seems also to be influenced by stroking parameters, with a direct relationship to stroke length and stroke index, and an inverse correlation with stroke rate. Assessing TLim-vVO2max, together with the anaerobic threshold and the biomechanical general parameters, will allow a larger spectrum of testing protocols application, helping to build more objective and efficient training programs.

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