Principles of Assessment, Prescription, and Exercise Program Adherence

Components of Physical Fitness

• Physical fitness is the ability to perform occupational, recreational, and daily activities without undue fatigue.

Five Aspects of Physical Fitness

• Cardiorespiratory endurance
• Musculoskeletal fitness
• Body weight and composition
• Flexibility
• Balance

Testing Order

• When conducting all tests in a single session, follow this sequence:
  • Resting blood pressure and heart rate
  • Body composition and balance
  • Cardiorespiratory endurance
  • Muscular fitness
  • Flexibility

Test Validity, Reliability, and Objectivity

• Validity: Accuracy of the assessment method
  • Validity coefficient should be ≥ $.80$
  • Small SEE (Standard Error of Estimate)
  • Good sensitivity and specificity
• Reliability: Reproducibility and repeatability of results
  • High reliability coefficient: ≥ $.90$
  • Poor reliability implies poor validity.
  • Good reliability does not guarantee good validity.
• Objectivity: Similar results obtained by similarly trained technicians when assessing the same client
  • High objectivity coefficient: ≥ $.90$

Prediction Equation Evaluation Considerations

• Prediction equation reference measure.
• Number of participants used for equation development.
• Ratio of sample size to predictor variables.
• Magnitude of prediction equation multiple regression coefficient ($R_{mc}$) and SEE.
• Applicability of the predictor equation.
• Measurement methods for prediction variables.
• Independent cross-validation with acceptable statistics.
• Small constant error.
• Magnitude of individual predictive accuracy.

Table 3.1: Direct (Reference) and Indirect (Field) Measures of Physical Fitness Components

• Cardiorespiratory Endurance
  • Laboratory Reference Measure: Maximal GXT with direct measurement of $VO_{2max}$
  • Indirect Measures/Field Tests: Submaximal GXT, distance run/walk tests, step tests
  • Group Prediction Error (SEE and TE): < 5.0 ml \. kg^{-1} \. min^{-1}
  • Individual Prediction Error: ±10 ml \. kg^{-1} \. min^{-1}
• Muscular Strength
  • Laboratory Reference Measure: Maximal force (kg) or torque (Nm) via isokinetic or 1-RM tests
  • Indirect Measures/Field Tests: Submaximal tests (2-RM to 10-RM value)
  • Group Prediction Error (SEE and TE): < $2.0 kg$
  • Individual Prediction Error: $±4 kg$
• Body Composition
  • Laboratory Reference Measure: $D_b$ (g/cc), FFM (kg), or %BF via hydrodensitometry or dual-energy X-ray absorptiometry
  • Indirect Measures/Field Tests: Bioimpedance, skinfolds, anthropometry
  • Group Prediction Error (SEE and TE):
    • $D_b$: < 0.0080 g \. cc^{-1}
    • FFM (men): < $3.5 kg$ ($±6.0 kg$)
    • FFM (women): < $2.8 kg$ ($±5.0 kg$)
    • %BF: < 3.5\%$BF (±7.0\%$)
• Flexibility
  • Laboratory Reference Measure: ROM at joint (degrees) via X-ray or goniometry
  • Indirect Measures/Field Tests: Linear measures of ROM
  • Group Prediction Error (SEE and TE): < 6°$</li> <li>Individual Prediction Error:$±12°$</li></ul></li> <li>Note:<ul> <li>$D_b$$ = total body density
  • FFM = fat-free mass
  • %BF = relative body fat
  • SEE = standard error of estimate
  • TE = total error
  • GXT = graded exercise test
  • ROM = range of motion
  • RM = repetition maximum
  • Nm = newton-meter

Test Administration and Interpretation

• Provide timely pretest instructions for the client regarding:
  • Attire
  • Food and beverage consumption
  • Avoiding strenuous physical activity prior to the test
  • Resting the night before
• Ensure test administration is well-practiced.
• Use positive and understandable terms when interpreting results for the client.

Basic Principles of Program Design

• Specificity of training
• Overload
• Progression
• Initial values
• Interindividual variability
• Diminishing returns
• Reversibility

Exercise Program Adherence

• Key to accomplishing the client’s goal.
• Learn what motivates the client (incentives, compliments, threat of disease).
• Implement strategies to avoid attrition:
  • Journaling
  • Achievable goals
  • Sense of control
• Help the client adopt behavior modification techniques.

Tips for Enhancing Exercise Motivation

• Understand why the client is there.
• Create opportunities for the client to:
  • Experience competence
  • Increase autonomy
  • Discover relatedness
• Avoid off-putting behaviors.
• Instill a sense of competency in the client.
• Foster intrinsic motivation for exercise.
• Integrate behavior modification model theories to encourage adherence.

Using Technology to Promote Physical Activity

• Wearable technology such as:
  • Pedometers
  • Accelerometers
  • Heart Rate monitors
  • GPS
• Integration of older and newer technologies:
  • Bluetooth
  • Apps
  • Social media
• Active workstations to decrease sedentary time at work.

Technology for Promoting Physical Activity (Continued)

• Pedometers:
  • Track steps.
  • Walking programs are beneficial for health.
  • Step-count criteria for moderate-intensity physical activity.
• Accelerometers:
  • Build on features of pedometers.
  • Record movement acceleration.
  • Can identify body position.
  • Neither accurately estimates the energy expenditure of exercise.
• Heart Rate Monitors:
  • Good way to monitor exercise intensity.
  • Accuracy is affected by several factors.
  • Heart rate monitoring via smartphone using photoplethysmography, where quality of skin and device contact is key.
  • Manufacturers’ app algorithms differ.