Un año de seguimiento con variabilidad de la frecuencia cardiaca en trail runners / One-year follow-up with heart rate variability in trail runners

Este estudio tuvo como objetivo analizar las medidas de variabilidad de la frecuencia cardíaca (VFC) para proporcionar valores de referencia en atletas de Ultra-Trail Running (UTR). Dieciséis UTR chilenos fueron monitoreados con registros basales al despertar de 5 minutos durante un año de seguimiento, tiempo en el cual, mantuvieron sus actividades habituales de entrenamiento, competición y descanso. Como variable para evaluar la actividad parasimpática la RMSSD (raíz cuadrada de la media de las diferencias de la suma de los cuadrados entre intervalos RR adyacentes) fue analizada. Además, se calculó el Stress Score (SS) como indicador de la actividad simpática. Los datos aportados proporcionan valores de referencia de VFC para UTR a través de una distribución de percentiles, que pueden ser particularmente útiles cuando la VFC se utiliza para el control de las cargas de entrenamiento en atletas de UTR. (AU)

This study aimed to analyze measures of heart rate variability (HRV) to provide reference values in Ultra-Trail Running (UTR) athletes. Sixteen Chilean UTR were monitored with 5-minute baseline wake-up records during a one-year follow-up during which they maintained their usual training, competition and rest activities. As a variable to evaluate parasympathetic activity the RMSSD (square root of the mean value of the sum of the squared differences of all successive RR intervals) was analyzed. In addition, the Stress Score (SS) was calculated as an indicator of sympathetic activity. The data provided are reference baseline HRV values for UTR through a percentile distribution, which can be particularly useful when HRV is used to control training loads in UTR athletes. (AU)

Non-linear heart rate dynamics during and after three controlled exercise intensities in healthy men.

We aimed to analyse the complexity and fractal nature of heartbeat during constant exercise, at three different intensities, and recovery.Fourteen healthy men underwent 4 separate sessions. The first session was an incremental treadmill test to determine ventilatory thresholds (VT1 and VT2) and maximal aerobic speed (MAS). Each subject ran at VT1 and VT2 speeds and MAS (second, third and fourth day). The duration of VT1 and VT2 loads were selected in such a way that the product intensity-duration (training load) was the same. Sample Entropy (SampEn) and slope of Detrended Fluctuation Analysis (DFA α1) were measured during the whole session.DFA α1 declines with exercise, being less in the VT1 trial than in the other two.SampEn shows no significant change during exercise. The three tests induce the same decline in SampEn, but at the highest intensity (MAS) tends to decline during the exercise itself, whereas at lower intensities (VT1, VT2) the decline is delayed (10 min of recovery). Subsequently, SampEn at VT1 gradually recovers, whereas at VT2 and MAS it remains stable during recovery.In conclusion, exercise produces a loss of heartbeat complexity, but not fractal nature, during recovery and it depends on intensity.

Carga de entrenamiento y VFC en una atleta femenina: estudio de caso / Training Load and HRV in a Female Athlete: A Case Study

El objetivo de este estudio fue describir una metodología de seguimiento en una atleta que combina el Ultra Trail Running (UTR) y el Ironman durante 16 semanas, mediante variabilidad de la frecuencia cardiaca (VFC). La carga de entrenamiento (CE) diaria se programó y se cuantificó el sumatorio semanal. Se registraron los intervalos RR (ms) en reposo cada mañana durante 5 minutos y a partir de ellos se midió la RMSSD (raíz cuadrada de la media de las diferencias de la suma de los cuadrados entre intervalos RR adyacentes) como medida de la actividad parasimpática y el índice de estrés (SS) como actividad simpática. Los registros diarios de VFC matutinos parecen ser una forma útil para monitorizar el estado de equilibrio simpático-parasimpático en deportistas antes de abordar las sesiones de entrenamiento. Esta monitorización serviría para detectar precozmente estados de fatiga y para poder monitorizar la planificación de las cargas

The purpose of this study was to describe a follow-up methodology in a female athlete who combines Ultra Trail Running (UTR) and Ironman during 16 weeks, using Heart Rate Variability (HRV). The daily training load (TL) was previously programmed and the weekly summation was recorded. The RR (ms) intervals at rest were recorded every morning for 5 minutes. The RMSSD (root mean square of the successive differences between adjacent RR intervals) was measured as an index of the parasympathetic activity and the stress score (SS) as a measure of sympathetic activity. Daily HRV morning records appear to be a useful way to monitor sympathetic-parasympathetic balance in athletes before tackling training sessions. This monitoring would serve to detect early fatigue states and to be able to monitor the planning of the loads