Comparison of Exercise Intensity Prescription
Condition: Cardiovascular Disease
MeSH terms: Cardiovascular Diseases
Study type: Interventional
Phase: Phase 2

Summary: 
      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.
    

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).
    

Intervention name(s): Exercise
Intervention type(s): Other
Intervention description(s): 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).
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Care Provider)
Primary purpose: Prevention
Keywords: primary prevention