ArticlePhysiological reports2021
Fractal correlation properties of heart rate variability as a biomarker of endurance exercise fatigue in ultramarathon runners.
Article in Physiological reports, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 27 papers.
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Who cites it
27 citing papers in PubMed.
- Recovery of Linear and Nonlinear Heart Rate Variability Metrics After Short-Term Moderate versus Vigorous Intensity Exercise: A Cross-Sectional Randomized Cross-Over Study.European journal of sport science · 2025Trial
- Correlation properties of heart rate variability for exercise prescription during prolonged running at constant speeds: A randomized cross-over trial.European journal of sport science · 2024Trial
- Fractal Properties of Heart Rate Dynamics: A New Biomarker for Anesthesia-Biphasic Changes in General Anesthesia and Decrease in Spinal Anesthesia.Sensors (Basel, Switzerland) · 2022Trial
- Kinetics of submaximal DFA α1 prior and post maximal efforts in trained and highly trained male and female cyclists.European journal of applied physiology · 2026Article
- Heart rate variability-guided endurance training: evaluating strengths, weaknesses, opportunities, and threats for load prescription and adjustment.Frontiers in sports and active living · 2026Article
- Non-linear heart rate variability is sensitive to exercise duration but not indicative of acute performance decrement.European journal of applied physiology · 2025Article
- Association of heart rate variability, exercise intensity and exercising arrhythmias with competition results in eventing horses.Equine veterinary journal · 2025Article
- Beyond FITT: addressing density in understanding the dose-response relationships of physical activity with health-an example based on brain health.European journal of applied physiology · 2025Review
- Correlation properties and respiratory frequency of ECG-derived heart rate variability during multiple race-pace running intervals in female and male long-distance runners.Physiological reports · 2025Article
- Quantifying exercise intensity with fractal correlation properties of heart rate variability: a study on incremental and constant-speed running.European journal of applied physiology · 2025Article
- An analysis of the 6-h ultra-marathon race using a machine learning approach.Frontiers in sports and active living · 2025Article
- Increased stress burden and electrodermal reactivity in bladder cancer patients in comparison to healthy controls.Heliyon · 2024Article
- Relationship of Cycling Power and Non-Linear Heart Rate Variability from Everyday Workout Data: Potential for Intensity Zone Estimation and Monitoring.Sensors (Basel, Switzerland) · 2024Article
- Reliability and validity of a non-linear index of heart rate variability to determine intensity thresholds.Frontiers in physiology · 2024Article
- The Between-Day Reliability of Correlation Properties of Heart Rate Variability During Running.Applied psychophysiology and biofeedback · 2023Article
- Effect of ramp slope on intensity thresholds based on correlation properties of heart rate variability during cycling.Physiological reports · 2023Article
- Validation of a non-linear index of heart rate variability to determine aerobic and anaerobic thresholds during incremental cycling exercise in women.European journal of applied physiology · 2023Article
- Long-term exercise adaptation. Physical aging phenomena in biological networks.Frontiers in network physiology · 2023Article
- Fractal correlation properties of HRV as a noninvasive biomarker to assess the physiological status of triathletes during simulated warm-up sessions at low exercise intensity: a pilot study.BMC sports science, medicine & rehabilitation · 2022Article
- Validity of the Polar H10 Sensor for Heart Rate Variability Analysis during Resting State and Incremental Exercise in Recreational Men and Women.Sensors (Basel, Switzerland) · 2022Article
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Authors and funding
4 authors.
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Abstract
Although heart rate variability (HRV) indexes have been helpful for monitoring the fatigued state while resting, little data indicate that there is comparable potential during exercise. Since an index of HRV based on fractal correlation properties, alpha 1 of detrended fluctuation analysis (DFA a1) displays overall organismic demands, alteration during exertion may provide insight into physiologic changes accompanying fatigue. Two weeks after collecting baseline demographic and gas exchange data, 11 experienced ultramarathon runners were divided into two groups. Seven runners performed a simulated ultramarathon for 6 h (Fatigue group, FG) and four runners performed daily activity over a similar period (Control group, CG). Before (Pre) and after (Post) the ultramarathon or daily activity, DFA a1, heart rate (HR), running economy (RE) and countermovement jumps (CMJ) were measured while running on a treadmill at 3 m/s. In Pre versus Post comparisons, data showed a decline with large effect size in DFA a1 post intervention only for FG (Pre: 0.71, Post: 0.32; d = 1.34), with minor differences and small effect sizes in HR (d = 0.02) and RE (d = 0.21). CG showed only minor differences with small effect sizes in DFA a1 (d = 0.19), HR (d = 0.15), and RE (d = 0.31). CMJ vertical peak force showed fatigue-induced decreases with large effect size in FG (d = 0.82) compared to CG (d = 0.02). At the completion of an ultramarathon, DFA a1 decreased with large effect size while running at low intensity compared to pre-race values. DFA a1 may offer an opportunity for real-time tracking of physiologic status in terms of monitoring for fatigue and possibly as an early warning signal of systemic perturbation.
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