Aerobic Reconditioning After Cardiac Surgery Using a Predictive Exercise Model

Aerobic Reconditioning in Post-Cardiac Surgery Patients: A Pragmatic Real-World Application of a Predictive Equation for Exercise Prescription

Brief Summary

After heart surgery, aerobic exercise is essential for recovery. Traditional exercise planning uses a cardiopulmonary exercise test (CPET), which may be unavailable early after surgery. This study tested a six-minute walk test (6MWT)-based method.

Patients aged 30-65 were randomized to either 6MWT-guided or symptom-guided exercise. They completed 14 supervised cycling sessions over two weeks. Safety, exercise progression, training volume, functional capacity, physical performance, and quality of life were measured.

Out of 118 patients, 109 completed the program with no serious exercise-related events. The 6MWT group started at higher intensity and achieved greater training volume. Both groups improved similarly in functional and quality-of-life measures, showing the 6MWT method is safe, feasible, and non-inferior to the traditional approach.

Study Overview

• Status: Completed
• Conditions: Rehabilitation; Post-cardiac Surgery
• Intervention / Treatment: Other: Equation-Based Aerobic Exercise Prescription; Other: Symptoms-Based Aerobic Exercise Prescription

Detailed Description

Aerobic exercise is essential in early cardiac rehabilitation after cardiac surgery. While cardiopulmonary exercise testing (CPET) is the reference standard, it is often impractical in the early postoperative phase. This single-center randomized controlled trial evaluated a six-minute walk test (6MWT)-derived predictive equation for exercise prescription versus a traditional symptoms-based approach (Borg CR10 scale).

Patients aged 30-65 years, admitted to inpatient rehabilitation one week after cardiac surgery (CABG, valve, or combined), were randomized 1:1 to 14 supervised cycling sessions over two weeks. Outcomes included feasibility, safety, workload progression, functional capacity (6MWT), physical performance (SPPB), and quality of life (EQ-5D).

Of 118 enrolled patients, 109 completed the program. No serious exercise-related adverse events occurred. The 6MWT-based group started at higher workloads and achieved greater cumulative training volume. Both groups improved in functional capacity, physical performance, and quality of life, demonstrating non-inferiority of the 6MWT method.

The 6MWT-derived predictive equation provides a safe, feasible, and effective alternative for aerobic exercise prescription when CPET is unavailable.

• Study Type: Interventional
• Enrollment (Actual): 118
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Italy
  • Pavia, Italy, 27100
    • Istituti Clinici Scientifici Maugeri IRCCS

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adult patients (≥18 years- 65 years) admitted to cardiac rehabilitation following cardiac surgery
• Clinically stable condition at the time of enrollment
• Ability to understand and sign informed consent
• ability to perform a six-minute walking test (6MWT) without assistive devices

Exclusion Criteria:

• Severe cognitive impairment preventing participation
• Unstable clinical conditions or acute complications
• Severe comorbidities limiting participation in rehabilitation
• Refusal or inability to provide informed consent

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Equation-Based Prescription; Participants in this group receive an aerobic exercise program based on a predictive equation derived from the six-minute walk test (6MWT). The maximal workload is estimated from 6MWT performance, and participants complete 14 supervised cycling sessions over two weeks. Exercise intensity is individually tailored and progressively increased according to the predictive equation.	Other: Equation-Based Aerobic Exercise Prescription; Patients performed 14 supervised cycling sessions over two weeks. Exercise workload was prescribed using a predictive equation derived from the six-minute walk test (6MWT) to estimate maximal workload. Progression was individualized based on calculated target workload.
Experimental: Symptoms-Based Prescription; Participants in this group receive an aerobic exercise program guided by perceived exertion, using the Borg CR10 scale (target 4-6). They complete 14 supervised cycling sessions over two weeks, with exercise intensity adjusted according to symptom feedback during each session.	Other: Symptoms-Based Aerobic Exercise Prescription; Patients performed 14 supervised cycling sessions over two weeks. Exercise workload was guided by perceived exertion using the Borg CR10 scale, targeting a rating of 4-6. Workload adjustments were made according to patient-reported symptom

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Functional Capacity (6-Minute Walk Test)	Distance covered during the 6-minute walk test (6MWT) to assess improvements in functional capacity following aerobic exercise prescription after cardiac surgery.	Baseline to 2 weeks (end of intervention)
Functional Capacity (6-Minute Walk Test)	Distance covered during the 6-minute walk test (6MWT) to assess improvements in functional capacity following aerobic exercise prescription	Baseline to 2 weeks (end of intervention)

Collaborators and Investigators

• Sponsor: Istituti Clinici Scientifici Maugeri SpA

Study record dates

Study Major Dates

• Study Start (Actual): March 30, 2022
• Primary Completion (Actual): April 30, 2024
• Study Completion (Actual): July 15, 2024

Study Registration Dates

• First Submitted: February 23, 2026
• First Submitted That Met QC Criteria: February 23, 2026
• First Posted (Actual): February 27, 2026

Study Record Updates

• Last Update Posted (Actual): March 3, 2026
• Last Update Submitted That Met QC Criteria: March 2, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: Aerobic Exercise; Functional Recovery; Exercise Prescription; 6-Minute Walk Test
• Other Study ID Numbers: ICS Maugeri; Ethics Committee (Other Identifier: Marmara University Faculty of Dentistry)

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