Aerobic Interval and Moderate Continuous Exercise Training on Ventricular Functions

Hypoxic exposure increases right ventricular (RV) afterload by triggering pulmonary hypertension, with consequent effects on the structure and function of the RV. Improved myocardial contractility is a critical circulatory adaptation to exercise training. However, the types of exercise that enhance right cardiac mechanics during hypoxic stress have not yet been identified. This study investigated how high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) influence right cardiac mechanics during hypoxic exercise (HE).

Study Overview

• Status: Completed
• Conditions: High Intensity Interval Training; Healthy; Exercise Training
• Intervention / Treatment: Behavioral: High intensity-interval training (HIIT); Behavioral: Moderate intensity-continuous (MICT)

Detailed Description

Hypoxic exposure increases right ventricular (RV) afterload by triggering pulmonary hypertension, with consequent effects on the structure and function of the RV. Improved myocardial contractility is a critical circulatory adaptation to exercise training. However, the types of exercise that enhance right cardiac mechanics during hypoxic stress have not yet been identified. This study investigated how high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) influence right cardiac mechanics during hypoxic exercise (HE).

The young and healthy sedentary males were randomly selected to engage in either HIIT (3-min intervals at 40% and 80% of VO2 oxygen uptake reserve) or MICT (sustained 60% of VO2 oxygen uptake reserve) for 30 min/day and 5 days/week for 6 weeks or were included in a control group (CTL) that did not engage in any exercise. Right cardiac mechanics during semiupright bicycle exercise tests under hypoxic conditions (i.e., 50 watts under 12% FiO2 for 3 min) were measured using two-dimensional speckle-tracking echocardiography. The primary outcome was the change in right cardiac mechanics during semiupright bicycle exercise under hypoxic conditions (i.e., 50 watts under 12% FiO2 for 3 min) as measured by two-dimensional speckle tracking echocardiography.

• Study Type: Interventional
• Enrollment (Actual): 54
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Taiwan
  • Taoyuan, Taiwan, 333
    • Chang Gung University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years to 30 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Male

Description

Inclusion Criteria:

• Having a sedentary lifestyle (without regular exercise, exercise frequency ≤ once weekly, duration < 20 min).

Exclusion Criteria:

• Exposed to high altitudes (> 3000 m) for at least 1 year.
• Smoker
• Taking medications or vitamins
• Having any cardiopulmonary/hematological risk.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: High intensity-interval training (HIIT); Subjects performed HIIT (3-min intervals at 40% and 80%VO2peak) on a bicycle ergometer for 30 min/day, 5 days/week for 6 weeks.	Behavioral: High intensity-interval training (HIIT); Subjects performed HIIT (3-min intervals at 40% and 80%VO2peak) on a bicycle ergometer for 30 min/day, 5 days/week for 6 weeks.
Experimental: Ｍoderate intensity-continuous (MCT); Subjects performed MICT (sustained 60%VO 2max) on a bicycle ergometer for 30 min/day, 5 days/week for 6 weeks.	Behavioral: Moderate intensity-continuous (MICT); Subjects performed MICT (sustained 60%VO 2max) on a bicycle ergometer for 30 min/day, 5 days/week for 6 weeks.
No Intervention: Control group; Without any exercise training

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The changes of right cardiac mechanics during hypoxia stress echocardiography: Strain	Hypoxia stress echocardiography was collected under hypoxic conditions (12% FiO2) and used two-dimensional Speckle-tracking echocardiography.; The resting images were acquired after the subject was placed in the aforementioned position for 10 min.; The exercise images were conducted using semirecumbent cycling with a 50-Watt resistance for 3 min and acquired at the third minute of cycling to ensure that subjects had reached a steady-state HR (i.e., HR changes <10 bpm within 10 s and <110-120 bpm).; A modified apical four-chamber view was used to assess 2D-STE longitudinal and radial parameters of the RV and RA.; The RV strain was calculated using the average peak segmental values displayed by the software using a 6-segment model.	8 weeks
The changes of right cardiac mechanics during hypoxia stress echocardiography: Strain rate	Hypoxia stress echocardiography was collected under hypoxic conditions (12% FiO2) and used two-dimensional Speckle-tracking echocardiography.; The resting images were acquired after the subject was placed in the aforementioned position for 10 min.; The exercise images were conducted using semirecumbent cycling with a 50-Watt resistance for 3 min and acquired at the third minute of cycling to ensure that subjects had reached a steady-state HR (i.e., HR changes <10 bpm within 10 s and <110-120 bpm).; A modified apical four-chamber view was used to assess 2D-STE longitudinal and radial parameters of the RV and RA.; The RV strain rate was calculated using the average peak segmental values displayed by the software using a 6-segment model.	8 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cardiopulmonary fitness	To assess cardiopulmonary fitness, cardiopulmonary exercise test (CPET) on a cycle ergometer was performed 4 days before and after the intervention. All subjects underwent exercise with a mask to measured oxygen consumption (VO2) breath by breath using a computer-based system (Master Screen CPX, Cardinal-health Germany).	8 weeks
The cavity diameters of RV	RV basal cavity diameter (RVD1), mid-cavity diameter (RVD2), and RV longitudinal diameter (RVD3), at end-diastole and end-systole, were evaluated in the modified apical four-chamber view.	8 weeks
Pulmonary vascular resistance (PVR)	Pulmonary vascular resistance (PVR) was calculated using the formula PVR = ([tricuspid regurgitation velocity/RVOT VTI] × 10 + 0.16); Tricuspid regurgitation velocity: Doppler imaging was used to measure peak tricuspid regurgitation velocities in systolic phase.; The RV outflow tract (RVOT): obtained from a parasternal short-axis base view modified apical four-chamber view, and the flow immediately proximal to the pulmonary artery valve during systole was detected to calculate both maximal velocity and pulsed-wave blood velocity time integral (VTI)	8 weeks
RV diastolic function	Doppler imaging was used to measure peak tricuspid annular (E') and flow velocities (E) in early diastole.	8 weeks
Tricuspid annular plane systolic excursion (TAPSE)	Tricuspid annular plane systolic excursion (TAPSE) measures the longitudinal excursion of the tricuspid annulus in one dimension, which was measured by M-mode.	8 weeks

Collaborators and Investigators

• Sponsor: Chang Gung Memorial Hospital
• Collaborators: National Science Council, Taiwan; Chang Gung University

Publications and helpful links

General Publications

• Fu TC, Wang CH, Lin PS, Hsu CC, Cherng WJ, Huang SC, Liu MH, Chiang CL, Wang JS. Aerobic interval training improves oxygen uptake efficiency by enhancing cerebral and muscular hemodynamics in patients with heart failure. Int J Cardiol. 2013 Jul 15;167(1):41-50. doi: 10.1016/j.ijcard.2011.11.086. Epub 2011 Dec 22.
• Wang Z, Chesler NC. Pulmonary vascular mechanics: important contributors to the increased right ventricular afterload of pulmonary hypertension. Exp Physiol. 2013 Aug;98(8):1267-73. doi: 10.1113/expphysiol.2012.069096. Epub 2013 May 10.
• Jaijee S, Quinlan M, Tokarczuk P, Clemence M, Howard LSGE, Gibbs JSR, O'Regan DP. Exercise cardiac MRI unmasks right ventricular dysfunction in acute hypoxia and chronic pulmonary arterial hypertension. Am J Physiol Heart Circ Physiol. 2018 Oct 1;315(4):H950-H957. doi: 10.1152/ajpheart.00146.2018. Epub 2018 May 18.
• Huang YC, Tsai HH, Fu TC, Hsu CC, Wang JS. High-Intensity Interval Training Improves Left Ventricular Contractile Function. Med Sci Sports Exerc. 2019 Jul;51(7):1420-1428. doi: 10.1249/MSS.0000000000001931.
• Naeije R, Badagliacca R. The overloaded right heart and ventricular interdependence. Cardiovasc Res. 2017 Oct 1;113(12):1474-1485. doi: 10.1093/cvr/cvx160.

Study record dates

Study Major Dates

• Study Start (Actual): July 1, 2016
• Primary Completion (Actual): June 30, 2017
• Study Completion (Actual): June 30, 2017

Study Registration Dates

• First Submitted: March 22, 2021
• First Submitted That Met QC Criteria: March 23, 2021
• First Posted (Actual): March 25, 2021

Study Record Updates

• Last Update Posted (Actual): March 25, 2021
• Last Update Submitted That Met QC Criteria: March 23, 2021
• Last Verified: March 1, 2021

More Information

Terms related to this study

• Keywords: High Intensity Interval Training; Stress echocardiography; Speckle-tracking echocardiography; Hypoxia test
• Other Study ID Numbers: 104-9615A3

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No