Comparison of Exercise Intensity Prescription

January 30, 2015 updated by: Lance Dalleck, Western Colorado University

Is a Threshold-Based Model a Superior Method to the Relative Percent Concept for Establishing Individual Exercise Intensity? A Randomized Controlled Trial

Therefore, the purpose of this study is to compare the effectiveness of two exercise training programs for improving cardiorespiratory fitness: the ACE three-zone training model (i.e., threshold based training) versus the more common ACSM recommended relative percent method (i.e., %HRR).

It is hypothesized that:

  1. The ACE three-zone training model will elicit greater mean changes in cardiorespiratory fitness (as measured by VO2max) when compared to the relative percent method.
  2. Participants in the ACE three-zone training model group will be more likely to have favorable VO2max responses; while comparatively, participants in the relative percent method group would be more likely to experience a VO2max nonresponse to exercise training.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

Cardiorespiratory fitness, typically determined by maximal oxygen uptake (VO2max), is a fundamental measurement for the exercise physiologist and other health professionals. VO2max refers to the highest rate at which oxygen can be taken up and consumed by the body during intense exercise. The "F.I.T.T." principle is an acronym for the four components for exercise prescription: frequency, intensity, time (length), and type of exercise.

Exercise intensity is arguably the most critical component of the exercise prescription model. Failure to meet minimal threshold values may result in lack of a training effect, while too high of an exercise intensity could lead to over-training and negatively impact adherence to an exercise program. The traditional reference standard for prescribing exercise intensity is expressed in terms of percentages of heart rate reserve (%HRR) or oxygen uptake reserve (%VO2R). This is considered the 'relative percent method'. The American College of Sports Medicine (ACSM) currently recommends an exercise intensity of 40-59% HRR/VO2R for improving and maintaining cardiorespiratory fitness. Nevertheless, despite a large evidence base supporting the ACSM relative percent concept recommendation for prescribing exercise intensity, there is concern that the approach consists of a very large range of acceptable percentages and fails to take into account individual metabolic responses to exercises. This study sought to compare the effectiveness of two exercise training programs for improving cardiorespiratory fitness: the ACE three-zone training model (i.e., threshold based training) versus the more common ACSM recommended relative percent concept (i.e., %HRR).

Apparently healthy, but sedentary men and women (n = 42) were randomized to a non-exercise control group or one of two exercise training groups. Exercise training was performed 30 min/day on 5 days/wk for 12wk according to one of two exercise intensity regimens: 1) a relative percent method was used in which intensity was prescribed according to percentages of heart rate reserve (HRR group), or 2) a threshold based method (ACE-3ZM) was used in which intensity was prescribed according to the first ventilatory threshold (VT1) and second ventilatory threshold (VT2).

Study Type

Interventional

Enrollment (Actual)

42

Phase

  • Phase 2

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 55 years (Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Participants were eligible for inclusion into the study if they were low-to-moderate risk as defined by the ACSM and sedentary.
  • Participants were also eligible for inclusion into the study if they verbally agreed to continue previous dietary habits and not perform additional exercise beyond that required for the present study.

Exclusion Criteria:

  • Exclusionary criteria included evidence of cardiovascular pulmonary, and/or metabolic disease.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Prevention
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Threshold based method
Exercise Week 1 Heart rate (HR) < first ventilatory threshold (VT1) 3 days 20 min/day Week 2 HR < VT1 4 days 25 min/day Week 3 HR < VT1 4 days 30 min/day Week 4 HR < VT1 5 days 30 min/day Week 5-6 HR ≥ VT1 to < second ventilatory threshold (VT2) 5 days 30 min/day Weeks 7-8 HR ≥ VT1 to < VT2 5 days 30 min/day Weeks 9-12 HR ≥ VT2 5 days 30 min/day
Other: Exercise
Continuous aerobic exercise prescribed according to two exercise intensity methods: threshold based method (i.e., ventilatory threshold) and relative percent method (i.e., heart rate reserve).
Experimental: Relative percent method
Exercise Week 1 40-45% heart rate reserve 3 days 20 min/day Week 2 40-45% heart rate reserve 4 days 25 min/day Week 3 40-45% heart rate reserve 4 days 30 min/day Week 4 40-45% heart rate reserve 5 days 30 min/day Week 5-6 50-55% heart rate reserve 5 days 30 min/day Weeks 7-8 50-55% heart rate reserve 5 days 30min/day Weeks 9-12 60-65% heart rate reserve 5 days 30 min/day
Other: Exercise
Continuous aerobic exercise prescribed according to two exercise intensity methods: threshold based method (i.e., ventilatory threshold) and relative percent method (i.e., heart rate reserve).
No Intervention: Control
Non-exercise control group

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Maximal oxygen uptake (VO2max) as a measure of cardiorespiratory fitness
Time Frame: 12 weeks
12 weeks
Estimate of 10-year Cardiovascular Disease Risk
Time Frame: 12 weeks
12 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Western Colorado University

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

May 1, 2014

Primary Completion (Actual)

January 1, 2015

Study Completion (Actual)

January 1, 2015

Study Registration Dates

First Submitted

January 22, 2015

First Submitted That Met QC Criteria

January 29, 2015

First Posted (Estimate)

January 30, 2015

Study Record Updates

Last Update Posted (Estimate)

February 3, 2015

Last Update Submitted That Met QC Criteria

January 30, 2015

Last Verified

January 1, 2015

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • WesternSCU

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Cardiovascular Disease

Clinical Trials on Exercise

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Kenya

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe