Dynamic characteristics of heart-rate responses to sine-function work-load patterns in man

Abstract

Dynamic characteristics of heart rate in response to sinusoidal variations of work load were analysed in 8 male and 3 female untrained students exercising in a sitting position on a bicycle ergometer. The mean work load was 90 watt in men and 60 watt in women, the amplitudes being 50 and 30 watt respectively. Nine different frequencies were used, the periods varying from 0.5 to 15.0 min. By means of harmonic analysis, the fundamental components in the response of the heart rate have been shown to prevail over the 2nd and 3rd harmonics, indicating a mainly linear behaviour of the control system in the work-load range studied. A comparison of the frequency response of untrained males and females observed in this study and of trained sportsmen, investigated by wigertz (1970), reveals differences between the groups. The individual and ensemble mean frequency responses have been described by several transfer functions, the best fit having been obtained with functions containing two time constants including one with a highly damped oscillating element. The dominating dynamic parameter is a time constant of about 20 to 30 sec. This time constant tends to be shorter and its portion of the frequency response diminishes in order from the untrained females and males to the trained sportsmen. The individual time constant decreases as the PWC170 increases, and is therefore a suitable criterion for estimating the physical performance of individuals under dynamic conditions.

Characteristics of Resonance in Heart Rate Variability Stimulated by Biofeedback

“…We theorize that resonant properties underlie CVS function variability (Vaschillo, Zingerman, Konstantinov, & Menitsky, 1983;Vaschillo et al, 2002). Rhythmical physical loading (Wigertz, 1971;Tiedt, Wohlgemuth, & Wohlgemuth, 1975), gravitation tilting (Hamilton, Lindan, & Reswick, 1969), rhythmical thermal stimulation (Lindqvist, 1990), rhythmical presentation of emotional pictures , and paced respiration all elicit high-amplitude oscillations in cardiovascular functions at resonant frequencies. HR resonance in the CVS at a frequency of ∼ 0.1 Hz has been discussed for more than 40 years.…”

Resonances in the cardiovascular system caused by rhythmical muscle tension

“…We previously showed that high‐amplitude 0.1 Hz HR oscillations were caused by emotional picture cue stimulation at a rate of 0.1 Hz (5 s picture on, 5 s picture off) (Vaschillo et al, 2008). Effects of rhythmical physical load on CVS functions also have been investigated (Lehrer, Vaschillo, Trost, & France, 2009; Tiedt, Wohlgemuth, & Wohlgemuth, 1975; Wigertz, 1971). The most comprehensive study (Wigertz, 1971) found that rhythmical physical loads varying from 250 to 1050 kpm/min at discrete frequencies in a range of 0.022–0.001 Hz (period range 0.75–16.67 min) caused sine‐wave oscillations in BP, HR, VT, partial O 2 pressure in blood (PO 2 ), respiration rate, and tidal volume.…”

Characterization of sports by the Vo2 dynamics of athletes in response to sinusoidal work load

“…It has recently been reported that the dynamic response to HR and Po, to changes in relative or absolute work load is closely correlated with VO,,,, in untrained men, in children and in athletes (Cooper et al 1985, Powers et al 1985, EBfeld et al 1987, Grucza et al 1989, Zhang et al 1991. I n addition, Tiedt et al (1975) reported that in the sinusoidal exercise test subjects with a higher physical work capacity a t a heart rate of 170 b.p.m. (PWC,,,) were characterized by a faster HR response.…”