The exercise intensity at maximal oxygen uptake (i⩒O2max): Methodological issues and repeatability

The aim of the present study was to investigate the effects of acute administration of taurine overload on time to exhaustion (TTE) of high-intensity running performance and alternative maximal accumulated oxygen deficit (MAODALT). The study design was a randomized, placebo-controlled, crossover design. Seventeen healthy male volunteers (age: 25 ± 6 years; maximal oxygen uptake: 50.5 ± 7.6 mL·kg−1·min−1) performed an incremental treadmill-running test until voluntary exhaustion to determine maximal oxygen uptake and exercise intensity at maximal oxygen uptake. Subsequently, participants completed randomly 2 bouts of supramaximal treadmill-running at 110% exercise intensity at maximal oxygen uptake until exhaustion (placebo (6 g dextrose) or taurine (6 g) supplementation), separated by 1 week. MAODALT was determined using a single supramaximal effort by summating the contribution of the phosphagen and glycolytic pathways. When comparing the results of the supramaximal trials (i.e., placebo and taurine conditions) no differences were observed for high-intensity running TTE (237.70 ± 66.00 and 277.30 ± 40.64 s; p = 0.44) and MAODALT (55.77 ± 8.22 and 55.06 ± 7.89 mL·kg−1; p = 0.61), which seem to indicate trivial and unclear differences using the magnitude-based inferences approach, respectively. In conclusion, acute 6 g taurine supplementation before exercise did not substantially improve high-intensity running performance and showed an unclear effect on MAODALT.

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Comparison of constant load exercise intensity for verification of maximal oxygen uptake following a graded exercise test in older adults

Physiological Reports ◽

10.14814/phy2.15037 ◽

2021 ◽

Vol 9 (18) ◽

Author(s):

Ian R. Villanueva ◽

John C. Campbell ◽

Serena M. Medina ◽

Theresa M. Jorgensen ◽

Shannon L. Wilson ◽

...

Keyword(s):

Older Adults ◽

Oxygen Uptake ◽

Exercise Intensity ◽

Exercise Test ◽

Maximal Oxygen Uptake ◽

Constant Load ◽

Graded Exercise Test ◽

Graded Exercise ◽

Constant Load Exercise

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Anaerobic contribution to the time to exhaustion at the minimal exercise intensity at which maximal oxygen uptake occurs in elite cyclists, kayakists and swimmers

European Journal of Applied Physiology ◽

10.1007/s004210050207 ◽

1997 ◽

Vol 76 (1) ◽

pp. 13-20 ◽

Cited By ~ 45

Author(s):

M. Faina ◽

V. Billat ◽

R. Squadrone ◽

M. De Angelis ◽

J. P. Koralsztein ◽

...

Keyword(s):

Oxygen Uptake ◽

Exercise Intensity ◽

Maximal Oxygen Uptake ◽

Time To Exhaustion ◽

Elite Cyclists

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Influence of exercise intensity on time spent at high percentage of maximal oxygen uptake during an intermittent session in young endurance-trained athletes

European Journal of Applied Physiology ◽

10.1007/s00421-007-0540-6 ◽

2007 ◽

Vol 102 (1) ◽

pp. 19-26 ◽

Cited By ~ 24

Author(s):

Delphine Thevenet ◽

Magaly Tardieu ◽

Hassane Zouhal ◽

Christophe Jacob ◽

Ben Abderraouf Abderrahman ◽

...

Keyword(s):

Oxygen Uptake ◽

Exercise Intensity ◽

Maximal Oxygen Uptake

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Substrate metabolism during different exercise intensities in endurance-trained women

Journal of Applied Physiology ◽

10.1152/jappl.2000.88.5.1707 ◽

2000 ◽

Vol 88 (5) ◽

pp. 1707-1714 ◽

Cited By ~ 139

Author(s):

J. A. Romijn ◽

E. F. Coyle ◽

L. S. Sidossis ◽

J. Rosenblatt ◽

R. R. Wolfe

Keyword(s):

Oxygen Uptake ◽

Exercise Intensity ◽

Maximal Oxygen Uptake ◽

High Intensity ◽

Fat Oxidation ◽

High Intensity Exercise ◽

Moderate Intensity ◽

Moderate Intensity Exercise ◽

Oxidation Rates ◽

Reported Data

We have studied eight endurance-trained women at rest and during exercise at 25, 65, and 85% of maximal oxygen uptake. The rate of appearance (Ra) of free fatty acids (FFA) was determined by infusion of [2H2]palmitate, and fat oxidation rates were determined by indirect calorimetry. Glucose kinetics were assessed with [6,6-2H2]glucose. Glucose Ra increased in relation to exercise intensity. In contrast, whereas FFA Ra was significantly increased to the same extent in low- and moderate-intensity exercise, during high-intensity exercise, FFA Ra was reduced compared with the other exercise values. Carbohydrate oxidation increased progressively with exercise intensity, whereas the highest rate of fat oxidation was during exercise at 65% of maximal oxygen uptake. After correction for differences in lean body mass, there were no differences between these results and previously reported data in endurance-trained men studied under the same conditions, except for slight differences in glucose metabolism during low-intensity exercise (Romijn JA, Coyle EF, Sidossis LS, Gastaldelli A, Horowitz JF, Endert E, and Wolfe RR. Am J Physiol Endocrinol Metab 265: E380–E391, 1993). We conclude that the patterns of changes in substrate kinetics during moderate- and high-intensity exercise are similar in trained men and women.

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The Determination of Step Frequency in 3-min Incremental Step-in-Place Tests for Predicting Maximal Oxygen Uptake from Heart Rate Response in Taiwanese Adults

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph19010563 ◽

2022 ◽

Vol 19 (1) ◽

pp. 563

Author(s):

Fang Li ◽

Chun-Hao Chang ◽

Chia-An Ho ◽

Cheng-You Wu ◽

Hung-Chih Yeh ◽

...

Keyword(s):

Heart Rate ◽

Oxygen Uptake ◽

Exercise Intensity ◽

Maximal Oxygen Uptake ◽

Prediction Models ◽

Cardiopulmonary Exercise Testing ◽

Standard Errors ◽

Step Frequency ◽

Significant Difference ◽

Incremental Step

The maximal oxygen uptake (VO2max) prediction models established by step tests are often used for evaluating cardiorespiratory fitness (CRF). However, it is unclear which type of stepping frequency sequence is more suitable for the public to assess the CRF. Therefore, the main purpose of this study was to test the effectiveness of two 3-min incremental step-in-place (3MISP) tests (i.e., 3MISP30s and 3MISP60s) with the same total number of steps but different step-frequency sequences in predicting VO2max. In this cross-sectional study, a total of 200 healthy adults in Taiwan completed 3MISP30s and 3MISP60s tests, as well as cardiopulmonary exercise testing. The 3MISP30s and 3MISP60s models were established through multiple stepwise regression analysis by gender, age, percent body fat, and 3MISP-heart rate. The statistical analysis included Pearson’s correlations, the standard errors of estimate, the predicted residual error sum of squares, and the Bland–Altman plot to compare the measured VO2max values and those estimated. The results of the study showed that the exercise intensity of the 3MISP30s test was higher than that of the 3MISP60s test (% heart rate reserve (HRR) during 3MISP30s vs. %HRR during 3MISP60s = 81.00% vs. 76.81%, p < 0.001). Both the 3MISP30s model and the 3MISP60s model explained 64.4% of VO2max, and the standard errors of the estimates were 4.2043 and 4.2090 mL·kg−1·min−1, respectively. The cross-validation results also indicated that the measured VO2max values and those predicted by the 3MISP30s and 3MISP60s models were highly correlated (3MISP30s model: r = 0.804, 3MISP60s model: r = 0.807, both p < 0.001). There was no significant difference between the measured VO2max values and those predicted by the 3MISP30s and 3MISP60s models in the testing group (p > 0.05). The results of the study showed that when the 3MISP60s test was used, the exercise intensity was significantly reduced, but the predictive effectiveness of VO2max did not change. We concluded that the 3MISP60s test was physiologically less stressful than the 3MISP30s test, and it could be a better choice for CRF evaluation.

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Reply to Gronwald et al.: Exercise intensity does indeed matter; maximal oxygen uptake is the gold-standard indicator

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1818247115 ◽

2018 ◽

Vol 115 (51) ◽

pp. E11892-E11893 ◽

Cited By ~ 3

Author(s):

Kazuya Suwabe ◽

Kyeongho Byun ◽

Kazuki Hyodo ◽

Zachariah M. Reagh ◽

Jared M. Roberts ◽

...

Keyword(s):

Oxygen Uptake ◽

Exercise Intensity ◽

Maximal Oxygen Uptake ◽

Gold Standard

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Determination of the exercise intensity that elicits maximal fat oxidation in individuals with obesity

Applied Physiology Nutrition and Metabolism ◽

10.1139/apnm-2016-0518 ◽

2017 ◽

Vol 42 (4) ◽

pp. 405-412 ◽

Cited By ~ 18

Author(s):

Sune Dandanell ◽

Charlotte Boslev Præst ◽

Stine Dam Søndergård ◽

Camilla Skovborg ◽

Flemming Dela ◽

...

Keyword(s):

Oxygen Uptake ◽

Exercise Intensity ◽

Maximal Oxygen Uptake ◽

Fat Oxidation ◽

Systematic Difference ◽

Exercise Protocol ◽

Continuous Exercise ◽

Graded Exercise ◽

Maximal Fat Oxidation

Maximal fat oxidation (MFO) and the exercise intensity that elicits MFO (FatMax) are commonly determined by indirect calorimetry during graded exercise tests in both obese and normal-weight individuals. However, no protocol has been validated in individuals with obesity. Thus, the aims were to develop a graded exercise protocol for determination of FatMax in individuals with obesity, and to test validity and inter-method reliability. Fat oxidation was assessed over a range of exercise intensities in 16 individuals (age: 28 (26–29) years; body mass index: 36 (35–38) kg·m−2; 95% confidence interval) on a cycle ergometer. The graded exercise protocol was validated against a short continuous exercise (SCE) protocol, in which FatMax was determined from fat oxidation at rest and during 10 min of continuous exercise at 35%, 50%, and 65% of maximal oxygen uptake. Intraclass and Pearson correlation coefficients between the protocols were 0.75 and 0.72 and within-subject coefficient of variation (CV) was 5 (3–7)%. A Bland−Altman plot revealed a bias of –3% points of maximal oxygen uptake (limits of agreement: –12 to 7). A tendency towards a systematic difference (p = 0.06) was observed, where FatMax occurred at 42 (40–44)% and 45 (43–47)% of maximal oxygen uptake with the graded and the SCE protocol, respectively. In conclusion, there was a high−excellent correlation and a low CV between the 2 protocols, suggesting that the graded exercise protocol has a high inter-method reliability. However, considerable intra-individual variation and a trend towards systematic difference between the protocols reveal that further optimization of the graded exercise protocol is needed to improve validity.

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