Ultra-Short-Term Heart Rate Variability Indexes at Rest and Post-Exercise in Athletes: Evaluating the Agreement with Accepted Recommendations

Figure 2. Bland-Altman plots comparing the ultra-short-term and criterion post-exercise log transformed root mean square of successive R-R interval differences (lnRMSSD) measures.The solid line represents the mean difference and the 2 outside dashed lines represent the upper and lower limits of agreement (± 1.96 SD of the mean difference).