A Test For Determining Critical Heart Rate Using The Critical Power Model

ABSTRACT Introduction: Heart rate (HR) has been a simple and easy-to-use physiological parameter widely used to determine exercise intensity. The critical power fatigue limit model, known as the critical heart rate (CHR), can be extrapolated to HR. However, an estimate for a CHR mathematical model has not yet been extrapolated for upper limb exercise in the elderly. Objective: To compare the mathematical model previously used to estimate CHR with the heart rate values at the critical power (CP) during arm-ergometer exercises in elderly subjects. Methods: After an initial maximum-incremental exercise test on a cycle arm-ergometer, seven elderly people performed four high-intensity constant-load tests to the limit of tolerance (Tlim), to determine CP and critical heart rate (CHR). For each power output, the heart rate of the last five seconds (HRlim) and total time to exhaustion (in minutes) were obtained. The slope coefficients of the regression lines between HRlim and Tlim were defined as CHR, and between Wlim and Tlim as CP. A square-wave test was performed on a different day, in the power determined as equivalent to CP, and the heart rate at CP (CPHR) was assessed. Results: The HR-Tlim relationship was found to be hyperbolic in all subjects, who were able to sustain upper-limb exercise at CP for 20 min. CP attained 66.8±9.4% of peak work rate in the ramp test. The real average HR measured in the CP test was strikingly similar to the CHR calculated by the mathematical model of PC (137.6±16.9 versus 139.7±13.3bpm, respectively, p=0.53). There was strong correlation between the real and the estimated CHR. Conclusion: This study indicated that the maximal sustainable exercise intensity can be based on a physiological variable such as HR, and the CHR test can define exercise endurance, which can be useful in performance assessment and training prescription. Level of evidence II; Diagnostic studies – Investigating a diagnostic test.

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Validating an Adjustment to the Intermittent Critical Power Model for Elite Cyclists—Modeling W′ Balance During World Cup Team Pursuit Performances

International Journal of Sports Physiology and Performance ◽

10.1123/ijspp.2020-0444 ◽

2021 ◽

pp. 1-6

Author(s):

Jason C. Bartram ◽

Dominic Thewlis ◽

David T. Martin ◽

Kevin I. Norton

Keyword(s):

Confidence Limit ◽

Critical Power ◽

Work Capacity ◽

Error Threshold ◽

Power Model ◽

World Cup ◽

Effective Use ◽

Exciting Development ◽

Elite Cyclists ◽

Intermittent Work

Purpose: Modeling intermittent work capacity is an exciting development to the critical power model with many possible applications across elite sport. With the Skiba 2 model validated using subelite participants, an adjustment to the model’s recovery rate has been proposed for use in elite cyclists (Bartram adjustment). The team pursuit provides an intermittent supramaximal event with which to validate the modeling of W′ in this population. Methods: Team pursuit data of 6 elite cyclists competing for Australia at a Track World Cup were solved for end W′ values using both the Skiba 2 model and the Bartram adjustment. Each model’s success was evaluated by its ability to approximate end W′ values of 0 kJ, as well as a count of races modeled to within a predetermined error threshold of ±1.840 kJ. Results: On average, using the Skiba 2 model found end W′ values different from zero (P = .007; mean ± 95% confidence limit, –2.7 ± 2.0 kJ), with 3 out of 8 cases ending within the predetermined error threshold. Using the Bartram adjustment on average resulted in end W′ values that were not different from zero (P = .626; mean ± 95% confidence limit, 0.5 ± 2.5 kJ), with 4 out of 8 cases falling within the predetermined error threshold. Conclusions: On average, the Bartram adjustment was an improvement to modeling intermittent work capacity in elite cyclists, with the Skiba 2 model underestimating the rate of W′ recovery. In the specific context of modeling team pursuit races, all models were too variable for effective use; hence, individual recovery rates should be explored beyond population-specific rates.

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The Critical Power Model as a Potential Tool for Anti-doping

Frontiers in Physiology ◽

10.3389/fphys.2018.00643 ◽

2018 ◽

Vol 9 ◽

Cited By ~ 5

Author(s):

Michael J. Puchowicz ◽

Eliran Mizelman ◽

Assaf Yogev ◽

Michael S. Koehle ◽

Nathan E. Townsend ◽

...

Keyword(s):

Critical Power ◽

Power Model ◽

Potential Tool

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Reliability of the Three-minute All-out Test for Non-motorized Treadmill Tethered Running

International Journal of Sports Medicine ◽

10.1055/s-0035-1565238 ◽

2016 ◽

Vol 38 (08) ◽

pp. 613-619 ◽

Cited By ~ 3

Author(s):

M. Gama ◽

F.A. Sousa ◽

I.G. dos Reis ◽

C. Gobatto

Keyword(s):

Critical Power ◽

Anaerobic Capacity ◽

Cycle Ergometer ◽

Power Model ◽

Single Test ◽

Physically Active ◽

Severe Intensity ◽

Protocol Adaptation ◽

Aerobic And Anaerobic ◽

Power Evaluation

AbstractThe 3-min all-out test was developed and validated on a cycle ergometer using a modification of a linear mathematical equation (1/time vs. power) obtained from the original critical power model. The purpose of this development was to obtain, in a single test, the aerobic and anaerobic capacity parameters and identify the exercise transition moment from heavy to severe intensity. The aim of this study was to propose an adaptation of the all-out 3-min cycle ergometer to a non-motorized treadmill with tethered running. In addition, we tested the reproducibility of this adapted protocol, highlighting the need for mechanical power evaluation using a specific ergometer. Consequently, 10 physically active individuals visited the laboratory 4 times for testing and data collection. The results suggested that the protocol adaptation for the 3-min all-out test for non-motorized treadmill with tethered running was reproducible and feasible. It was also possible to show that the AO3 application in this ergometer ensures the specificity of the sports that involve the running exercise, from assessment of both aerobic and anaerobic parameters, accomplished in a single day of application.

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Influence of the Chainring Geometry on the Critical Power of Recreational Cyclists

Volume 4: 22nd International Conference on Advanced Vehicle Technologies (AVT) ◽

10.1115/detc2020-22752 ◽

2020 ◽

Author(s):

Orlando Acevedo ◽

Luis Muñoz ◽

Alejandra Polanco ◽

Daniel Suárez

Keyword(s):

Performance Improvement ◽

Power Output ◽

Critical Power ◽

Power Delivery ◽

Power Model ◽

Pilot Test ◽

Real Effect ◽

Test Conditions ◽

Endurance Tests ◽

Long Endurance

Abstract Science has come to a disagreement regarding the real effect that chainrings’ geometry has on cyclists’ performance. In this study, the influence of the use of a noncircular chainring on recreational cyclists’ performance is determined through experimental power delivery tests. A critical power model was used to estimate variations on cyclists’ performance. In addition, a new protocol for estimating critical power was proposed. Fourteen recreational cyclists (two females and twelve males) performed a series of self-paced constant-time tests with a circular and a noncircular (i.e., Osymetric) chainring during two different test sessions. Power output, cadence and time were registered to compute the critical power. According to the results of this study, it seems there is a change in the critical power of the majority of the recreational cyclists due to the use of a noncircular chainring. Thus, a performance improvement was obtained during long-endurance tests. However, the order of the tests (i.e., starting with the circular chainring or starting with the noncircular chainring) was proven to have an impact on the results due to a familiarization effect to the test conditions. Finally, a new protocol to estimate the critical power of a cyclist by performing a single riding session was proposed and assessed on a pilot test (i.e., error < 3%).

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