ArticleEuropean journal of applied physiology2026
Validity of an open-source mobile app to measure fractal correlation properties of heart rate variability during exercise.
Article in European journal of applied physiology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 6 papers.
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Who cites it
6 citing papers in PubMed.
- Correlation Properties of Heart Rate Variability for Exercise Intensity Monitoring and Prescription During Constant-Load Cycling: A Comparison With Traditional Physiological Variables.European journal of sport science · 2026Article
- Noninvasive assessment of the anaerobic threshold in endurance athletes: an evidence-based narrative review of methods, validity, and field feasibility.British medical bulletin · 2026Review
- 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
- Validity of an open-source mobile app to measure fractal correlation properties of heart rate variability during exercise.European journal of applied physiology · 2026Article
- Agreement between heart rate variability-derived and lactate/ventilatory thresholds during a 4-min stepwise incremental cycling test in male adults.Physiological reports · 2026Article
- Prehypertension in young physically active adults: early vascular alterations and implications for exercise-intensity prescription.Frontiers in cardiovascular medicine · 2026Article
Corrections and comments
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Authors and funding
3 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
purposeThe nonlinear index of heart rate (HR) variability (HRV), based on detrended fluctuation analysis (DFA a1), is recognized for its value in assessing endurance exercise intensity thresholds and autonomic durability. However, a constraint to widespread implementation is lack of a low cost, real-time solution. This study examined whether a free, open-source Android application (Fatmaxxer) could provide reasonable agreement and correlation with the established standard of Kubios HRV software.
methodsTwenty-three participants (10 males) underwent incremental step-ramp-step cycling testing measuring gas exchange variables with recording of raw RR intervals and Fatmaxxer computed DFA a1. The raw RR series was processed by Kubios HRV software for comparisons of HRV HR thresholds (HRVT
resultsBased on t testing, Wilcoxon sign rank testing and Bland Altman analysis, there were small differences present in the direct comparison of DFA a1 responses in the incremental ramp and 10-minute constant interval (bias 0.03-0.05 respectively). Despite this bias, the mean HRVT1/2 determinations were within 1 bpm and the first HRVT comparisons equivalent. All regressions showed excellent alignment with Pearson's r/Spearman's correlation/ICC above 0.96.
conclusionsThe DFA a1 responses and HRVTs derived from Fatmaxxer closely aligned with those obtained from the established standard Kubios HRV software. This highlights the utility of Fatmaxxer as a free, open-source Android platform capable of real-time monitoring, supporting broader accessibility of DFA a1 tracking.
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