The Astrand-Ryhming nomogram revisited

1986 ◽  
Vol 61 (3) ◽  
pp. 1203-1209 ◽  
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).

Cardiovascular response to cycle exercise during and after pregnancy

1989 ◽  
Vol 66 (1) ◽  
pp. 336-341 ◽  
Author(s):  
S. P. Sady ◽  
M. W. Carpenter ◽  
P. D. Thompson ◽  
M. A. Sady ◽  
B. Haydon ◽  
...  
Keyword(s):  
Heart Rate ◽  
Maximal Exercise ◽  
Cardiovascular Response ◽  
Work Load ◽  
Cycle Ergometry ◽  
Maximal Heart Rate ◽  
O2 Uptake ◽  
Cycle Exercise ◽  
Vascular Beds ◽  
Response To Exercise

Our purpose was to determine if pregnancy alters the cardiovascular response to exercise. Thirty-nine women [29 +/- 4 (SD) yr], performed submaximal and maximal exercise cycle ergometry during pregnancy (antepartum, AP, 26 +/- 3 wk of gestation) and postpartum (PP, 8 +/- 2 wk). Neither maximal O2 uptake (VO2max) nor maximal heart rate (HR) was different AP and PP (VO2 = 1.91 +/- 0.32 and 1.83 +/- 0.31 l/min; HR = 182 +/- 8 and 184 +/- 7 beats/min, P greater than 0.05 for both). Cardiac output (Q, acetylene rebreathing technique) averaged 2.2 to 2.8 l/min higher AP (P less than 0.01) at rest and at each exercise work load. Increases in both HR and stroke volume (SV) contributed to the elevated Q at the lower exercise work loads, whereas an increased SV was primarily responsible for the higher Q at higher levels. The slope of the Q vs. VO2 relationship was not different AP and PP (6.15 +/- 1.32 and 6.18 +/- 1.34 l/min Q/l/min VO2, P greater than 0.05). In contrast, the arteriovenous O2 difference (a-vO2 difference) was lower at each exercise work load AP, suggesting that the higher Q AP was distributed to nonexercising vascular beds. We conclude that Q is greater and a-vO2 difference is less at all levels of exercise in pregnant subjects than in the same women postpartum but that the coupling of the increase in Q to the increase in systemic O2 demand (VO2) is not different.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of airflow and work load on cardiovascular drift and skin blood flow

1984 ◽  
Vol 56 (5) ◽  
pp. 1411-1417 ◽  
Author(s):  
J. D. Shaffrath ◽  
W. C. Adams
Keyword(s):  
Heart Rate ◽  
Blood Flow ◽  
Skin Blood Flow ◽  
Prolonged Exercise ◽  
Work Load ◽  
Progressive Increase ◽  
Cycle Ergometry ◽  
O2 Uptake ◽  
Mean Values ◽  
Cardiovascular Drift

Cardiovascular drift (CVD) can be defined as a progressive increase in heart rate (HR), decreases in stroke volume (SV) and mean arterial pressure (MAP), and a maintained cardiac output (Q) during prolonged exercise. To test the hypothesis that the magnitude of CVD would be related to changes in skin blood flow ( SkBF ), eight healthy, moderately trained males performed 70-min bouts of cycle ergometry in a 2 X 2 assortment of airflows (less than 0.2 and 4.3 m X s-1) and relative work loads (43.4% and 62.2% maximal O2 uptake). Ambient temperature and relative humidity were controlled to mean values of 24.2 +/- 0.8 degrees C and 39.5 +/- 2.4%, respectively. Q, HR, MAP, SkBF , skin and rectal temperatures, and pulmonary gas exchange were measured at 10-min intervals during exercise. Between the 10th and 70th min during exercise at the higher work load with negligible airflow, HR and SkBF increased by 21.6 beats X min-1 and 14.0 ml X 100 ml-1 X min-1, respectively, while SV and MAP decreased by 16.4 ml and 11.3 mmHg. The same work load in the presence of 4.3 m X s-1 airflow resulted in nonsignificant changes of 7.6 beats X min-1, 4.0 ml X (100 ml-1 X min)-1, -2.7 ml, and -1.7 mmHg for HR, SkBF , SV, and MAP. Since nonsignificant changes in HR, SkBF , SV, and MAP were observed at the lower work load in both airflow conditions, the results emphasize that CVD occurs only in conditions which combine high metabolic and thermal circulatory demands.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of beta-adrenergic blockade on ventilation and gas exchange during exercise in humans

1983 ◽  
Vol 54 (5) ◽  
pp. 1306-1313 ◽  
Author(s):  
E. S. Petersen ◽  
B. J. Whipp ◽  
J. A. Davis ◽  
D. J. Huntsman ◽  
H. V. Brown ◽  
...  
Keyword(s):  
Heart Rate ◽  
Gas Exchange ◽  
Time Constant ◽  
Minute Ventilation ◽  
Work Rate ◽  
Beta Blockade ◽  
Adrenergic Blockade ◽  
O2 Uptake ◽  
Beta Adrenergic ◽  
Co2 Partial Pressure

The effects of beta-adrenergic blockade induced by intravenous propranolol hydrochloride (0.2 mg/kg) on ventilatory and gas exchange responses to exercise were studied during tests in which the work rate was either increased progressively or maintained at a constant load in six healthy young male subjects. Heart rate during exercise decreased by about 20% and cardiac output, as estimated by a modification of the method of Kim et al. (J. Appl. Physiol. 21: 1338–1344, 1966), by about 15%. The relation between work rate and O2 uptake (VO2) was unaffected by propranolol, whereas maximal O2 uptake (VO2max) decreased by 5% and the anaerobic threshold, estimated noninvasively, was lowered by 23%. The relations between CO2 output (VCO2) and end-tidal CO2 partial pressure (PCO2) and between VCO2 and minute ventilation (VE) were both unaffected. The time constants for changes of VO2, VCO2, and VE during on-transients from unloaded pedaling to either a moderate (ca. 50% VO2max) or a heavy (ca. 67% VO2max) work rate in the control studies were in agreement with previously reported values, i.e., 42, 60, and 69 s, respectively. beta-Blockade was associated with a significantly increased time constant for VO2 of 61 s but with less consistent and insignificant changes for VCO2 and VE. There was a small but significant increase of the time constant for heart rate from 40 to 45 s. It is concluded that propranolol exerts its primary influence during exercise on the cardiovascular system without any discernible effect on ventilatory control.

O2 uptake kinetics above and below the lactic acidosis threshold during sinusoidal exercise

1993 ◽  
Vol 75 (4) ◽  
pp. 1683-1690 ◽  
Author(s):  
P. Haouzi ◽  
Y. Fukuba ◽  
R. Casaburi ◽  
W. Stringer ◽  
K. Wasserman
Keyword(s):  
Heart Rate ◽  
Lactic Acidosis ◽  
State Level ◽  
Sine Wave ◽  
Work Rate ◽  
Phase Lag ◽  
O2 Uptake ◽  
O2 Transport ◽  
Vo2 Kinetics ◽  
Lactic Acidosis Threshold

O2 uptake (VO2) kinetics at the onset of a constant work rate exercise are difficult to describe for work rates above the lactic acidosis threshold (LAT), because the steady-state level of VO2 response can usually not be identified. To describe the ability of the O2 transport system to deliver and the cells to utilize O2 above the LAT relative to that below the LAT, we applied a fluctuating (sinusoidal) variation of work rate. After 4 min of constant work at the midpoint of the sinusoidal work rate, a fluctuating work rate, at a period of 4 min, was applied below the LAT for the next 16 min. This was repeated in a range of work rates above the LAT with the same sine-wave amplitude. VO2 response appeared to follow a sinusoidal pattern similar to that of work rate for below- and above-LAT exercise. However, the amplitude of the VO2 response was significantly reduced (5.4 +/- 2.6 vs. 7.6 +/- 1.9 ml.min-1 x W-1, P < 0.01), and the phase lag increased above- compared with below-LAT work rate. VO2/heart rate fluctuations were dramatically reduced, whereas heart rate amplitude decreased and phase lag increased, for above-LAT sinusoidal work rate changes. These results suggest that VO2 kinetics are slowed in the work rate domain above the LAT relative to that below the LAT and that VO2 kinetics could be limited by the O2 transport mechanisms to the exercising muscle.

A test to establish maximum O2 uptake despite no plateau in the O2 uptake response to ramp incremental exercise

2006 ◽  
Vol 100 (3) ◽  
pp. 764-770 ◽  
Author(s):  
H. B. Rossiter ◽  
J. M. Kowalchuk ◽  
B. J. Whipp
Keyword(s):  
Test Session ◽  
Cycle Ergometry ◽  
Work Rate ◽  
Single Test ◽  
Healthy Male ◽  
O2 Uptake ◽  
Ramp Test ◽  
Maximum Effort ◽  
Response Profiles ◽  
Final Work

The O2 uptake (V̇o2) response to ramp incremental (RI) exercise does not consistently demonstrate plateau-like behavior at the limit of tolerance, and hence the requirements for a maximum V̇o2 commonly are not met, despite apparent maximum effort. We sought to determine whether an appended step exercise (SE) test at a work rate greater than that achieved in a preceding ramp test would establish the plateau criterion. Seven healthy male adults performed RI cycle ergometry (20 W/min) to the limit of tolerance, followed by 5-min recovery (20 W) and then an SE test at 105% (RISE-105) of the final work rate (WRpeak) achieved during RI. Five of these subjects also performed an RI test followed by SE at 95% WRpeak (RISE-95). V̇o2 was measured breath by breath using a turbine and mass spectrometer. The average of the final 15 s of RI or SE was used to establish respective V̇o2 peaks. When V̇o2 peak was approached, a constant V̇o2 value (e.g., a plateau) was not discernable during any RI or SE component of the tests. Although the WRpeak [mean (SD)] was higher during the SE portion [359 W (SD 31)] than during the RI portion [341 W (SD 29)] of the RISE-105, the peak V̇o2 was not different [SE, 4.30 l/min (SD 0.51); RI, 4.33 l/min (SD 0.52); P = 0.49; n = 7]. Similarly, in the RISE-95 test, WRpeak was 310 W (SD 31) for the SE portion and 326 W (SD 32) for the RI portion, yet the peak V̇o2 values were not different [SE, 4.12 l/min (SD 0.53); RI, 4.11 l/min (SD 0.48); P = 0.78; n = 5]. The lack of notable difference between the V̇o2 peaks established at different WRpeak values in our RISE protocols provides the plateau criterion for verification of maximum V̇o2 in a single test session, even when the data response profiles do not themselves evidence a plateau.

Endurance training of older men: responses to submaximal exercise

1992 ◽  
Vol 73 (2) ◽  
pp. 452-457 ◽  
Author(s):  
M. J. Poulin ◽  
D. H. Paterson ◽  
D. Govindasamy ◽  
D. A. Cunningham
Keyword(s):  
Heart Rate ◽  
Oxygen Uptake ◽  
Training Program ◽  
Performance Test ◽  
Older Men ◽  
Constant Load ◽  
Submaximal Exercise ◽  
Work Rate ◽  
Performance Time ◽  
Before And After

The purpose of this study was to quantify the exercise response of older subjects on a time-to-fatigue (TTF) submaximal performance test before and after a training program. Eight older men (67.4 +/- 4.8 yr) performed two maximal treadmill tests to determine maximum oxygen uptake (VO2max) and ventilation threshold (TVE) and a constant-load submaximal exercise treadmill test that required an oxygen uptake (VO2) between TVE and VO2max. The submaximal test, performed at the same absolute work rate before and after the training program, was performed to volitional fatigue to measure endurance time. The men trained under supervision at an individualized pace representing approximately 70% of VO2max (80% maximum heart rate) for 1 h, four times per week for 9 wk. Significant increases were demonstrated for VO2max (ml.kg-1.min-1; 10.6%); maximal ventilation (VE, l/min; 11.6%), and TVE (l/min; 9.8%). Weight decreased 2.1%. Performance time on the TTF test increased by 180% (7.3 +/- 3.0 to 20.4 +/- 13.5 min). The similar end points for VO2, VE, and heart rate during the TTF and maximal treadmill tests established that the TTF test was stopped because of physiological limitations. The increase in performance time among the subjects was significantly correlated with improvements in VO2max and TVE, with the submaximal work rate representing a VO2 above TVE by 88% of the difference between TVE and VO2max pretraining and 73% of this difference on posttraining values.

Cardiac Autonomic Modulation of Heart Rate Recovery in Children with Spina Bifida

2021 ◽  
Author(s):  
Marisa Maia Leonardi-Figueiredo ◽  
Gabriela Barroso de Queiroz Davoli ◽  
Amanda Evangelista Avi ◽  
Julio Cesar Crescêncio ◽  
Silvia Cristina Moura-Tonello ◽  
...  
Keyword(s):  
Heart Rate ◽  
Spina Bifida ◽  
Physical Fitness ◽  
Children And Adolescents ◽  
Heart Rate Recovery ◽  
Recovery Phase ◽  
Gas Analysis ◽  
Exercise Heart Rate ◽  
O2 Pulse ◽  
Analysis System

AbstractWe aimed to analyse cardiac autonomic control by assessing the post-exercise heart rate recovery (HRR) and physical fitness in children and adolescents with spina bifida (SB), compared to participants with typical development. A total of 124 participants, 42 with spina bifida (SB group) and 82 typical developmental controls (CO group) performed the arm cranking exercise test with a gas analysis system. HRR was determined at the first (HRR_1) and second (HRR_2) minute at recovery phase. Data are shown as [mean difference (95% CI)]. The SB group showed reduced HR reserve [14.5 (7.1–22.0) bmp, P<0.01], slower HRR_1 [12.4 (7.4–17.5) bpm, P<0.01] and HRR_2 [16.3 (10.6–21.9) bpm; P<0.01], lower VO2peak [VO2peak relative: 7.3 (4.2–10.3) mL·min−1·kg−1, P<0.01; VO2peak absolute: 0.42 (0.30–0.54) L·min−1, P<0.01], and lower O2 pulse [2.5 (1.8–3.2) mL·bpm, P<0.01] and ventilatory responses [13.5 (8.8–18.1) L·min−1, P<0.01] than the CO group. VE/VO2 was not different between groups [−2.82 (−5.77– −0.12); P=0.06], but the VE/VCO2 [−2.59 (−4.40–0.78); P<0.01] and the values of the anaerobic threshold corrected by body mass [−3.2 (−5.8– −0.6) mL·min−1·kg−1, P=0.01] were higher in the SB group than in the CO group. We concluded that children and adolescents with SB have reduced physical fitness and a slower HRR response after maximal effort.

Maximal aerobic exercise in pregnant women: heart rate, O2 consumption, CO2 production, and ventilation

1991 ◽  
Vol 70 (3) ◽  
pp. 1016-1023 ◽  
Author(s):  
F. K. Lotgering ◽  
M. B. van Doorn ◽  
P. C. Struijk ◽  
J. Pool ◽  
H. C. Wallenburg
Keyword(s):  
Heart Rate ◽  
Aerobic Power ◽  
Treadmill Exercise ◽  
Statistical Significance ◽  
Maximal Aerobic Power ◽  
Co2 Production ◽  
Maximal Heart Rate ◽  
O2 Uptake ◽  
Positive Linear Correlation ◽  
The Relationship

This study was to determine whether pregnancy affects maximal aerobic power. We measured heart rate, O2 uptake (VO2), CO2 production (VCO2), and ventilation at rest and during bicycle (BE) and treadmill exercise (TE) tests with rapidly increasing exercise intensities at 16, 25, and 35 wk gestation and 7 wk after delivery. Maximal heart rate was slightly lower throughout pregnancy compared with the nonpregnant state during both BE [174 +/- 2 vs. 178 +/- 2 (SE) beats/min] and TE (178 +/- 2 vs. 183 +/- 2 beats/min). Maximal VO2 was unaffected by pregnancy during BE and TE (2.20 +/- 0.08, 2.16 +/- 0.08, 2.15 +/- 0.08, and 2.19 +/- 0.08 l/min for BE and 2.45 +/- 0.08, 2.38 +/- 0.09, 2.33 +/- 0.09, and 2.39 +/- 0.08 l/min for TE at 16, 25, and 35 wk gestation and 7 wk postpartum, respectively). As a result of increased VO2 at rest, the amount of O2 available for exercise (exercise minus rest) tended to decrease with advancing gestation, reaching statistical significance only during TE at 35 wk gestation (1.99 +/- 0.08 l/min vs. 2.10 +/- 0.08 l/min postpartum). Power showed a positive linear correlation with O2 availability during BE as well as TE, and the relationship was unaffected by pregnancy.(ABSTRACT TRUNCATED AT 250 WORDS)

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