Acute Cardiorespiratory Responses to Different Exercise Modalities in Chronic Heart Failure Patients—A Pilot Study

Abstract

The purpose of this study was to compare the acute cardiorespiratory responses and time spent above different %VO2peak intensities between three “iso-work” protocols: (a) a high intensity interval training protocol (HIIT), (b) a higher intensity continuous protocol (CON70) and (c) a lower intensity continuous protocol (CON50) in patients with chronic heart failure (CHF). Ten male CHF patients (aged 55.1 ± 16.2 years) performed in separate days a single session of a HIIT protocol consisted of 4 sets × 4 min cycling at 80% VO2peak with 3 min of recovery at 50% VO2peak, a CON70 protocol corresponding to 70% VO2peak and a CON50 protocol corresponding to 50% VO2peak. Cardiopulmonary data were collected by an online gas analysis system. The HIIT and CON70 elicited higher cardiorespiratory responses compared to CON50 with no differences between them (p > 0.05). In HIIT and CON70, patients exercised longer at >80% and >90% VO2peak. The completion rate was 100% for the three protocols. Not any adverse events were observed in either protocol. Both HIIT and CON70 elicited a stronger physiological stimulus and required shorter time than CON50. Both HIIT and CON70 also induced comparable hemodynamic responses and ventilatory demand.

Towards a More Individually Tailored Exercise Prescription for Promoting Cardiovascular Health

“…ET is strongly recommended for patients with CHF since it improves exercise tolerance and quality of life [3]. The use of moderate continuous training is supported by robust evidence and represents the gold standard for these patients [13,14]; however, high-intensity exercise and RE can produce additional benefits [15]; therefore, the strategy of adopting a more individualized approach in exercise prescription, pursuing the goal of maximizing the benefits in each patient is now widely adopted [16].…”

“…The use of moderate continuous training is supported by robust evidence and represents the gold standard for these patients [13,14]; however, high-intensity exercise and RE can produce additional benefits [15]; therefore, the strategy of adopting a more individualized approach in exercise prescription, pursuing the goal of maximizing the benefits in each patient is now widely adopted [16]. Karatzanos et al [3] tested the acute cardiorespiratory response of CHF patients to single exercise sessions at three different intensities: high-intensity interval, high-intensity continuous, and low-intensity continuous exercises. They found similar increases in oxygen consumption at peak exercise (VO 2 peak) between high-intensity intervals and high-intensity continuous exercises, while low-intensity continuous exercise elicited more modest VO 2 peak increases.…”

“…For example, the intensity and volume of ET needed to optimize cardiovascular benefits in different clinical contexts remain uncertain; similarly, several mechanisms through which ET carries out its cardiovascular effects are still unclear; lastly, in order to develop an increasingly individually tailored ET prescription, further studies that include specific populations underrepresented in previous trials are needed. This Special Issue collects seven original articles and three reviews evaluating the effects of ET in a wide range of clinical conditions: four out of ten papers deal with ET in chronic heart failure (CHF) [3][4][5][6]; two with benefits of ET in subjects with congenital heart disease (CHD) [7,8]; two with blood pressure (BP) responses to acute or long-term exercise [9,10]; one with cardiovascular response to resistance exercise (RE) in elderly [11] and one with clinical consequences of coronavirus disease (COVID-19) in athletes [12].…”