2.4: Assessing Physical Fitness

Assessing Physical Fitness

Assessing physical fitness is essential for understanding an individual's current health status and designing effective exercise programs. Regular assessments can track progress, identify areas for improvement, and help prevent injuries by ensuring exercises are appropriately challenging. Below, we provide simple methods for estimating cardiorespiratory fitness, muscular fitness, and flexibility using minimal equipment.

Cardiorespiratory Fitness

Cardiorespiratory fitness is often measured by VO₂max, which represents the maximum amount of oxygen your body can utilize during intense exercise. VO₂max is a gold standard measure of aerobic capacity and an important indicator of overall cardiovascular and respiratory health. While VO₂max can be directly measured using specialized laboratory equipment, such tests are expensive and not widely accessible. Alternatively, VO₂max can be estimated by comparing the physical work required to complete a specific activity with the corresponding heart rate. This provides a practical and cost-effective way to assess cardiorespiratory fitness in various settings.

Taking Your Heart Rate

While you can measure your heart rate at the neck, chest, or wrist, the wrist (radial pulse) is the recommended location for accuracy and convenience. Locate the radial artery on the wrist, in line with the thumb. Place the tips of your index and middle fingers over the artery and apply light pressure. Do not use your thumb as it has its own pulse and may affect accuracy. Count the beats for a full 60 seconds, or count for 30 seconds and multiply by 2. Start the count on the first beat, which is counted as "zero."

Queen's College Step Test

This test estimates VO₂max based on heart rate recovery after a stepping exercise.

1. Equipment: A 16.25-inch step and a stopwatch.
2. Procedure:
   • Step in an up, up, down, down pattern at a rate of 22 steps/min for females and 24 steps/min for males, following a metronome.
   • Continue for 3 minutes.
   • Immediately after stopping, measure heart rate for 15 seconds and multiply by 4 to calculate beats per minute (bpm).
3. Formula:
   • VO₂max (mL/kg/min) = 111.33 - (0.42 × heart rate in bpm).

Rockport 1.5 Mile Walk Test

This test evaluates VO₂max by measuring the time taken to cover 1.5 miles.

1. Equipment: Stopwatch and a flat, measured course.
2. Procedure:
   • Warm up for 5–10 minutes.
   • Walk 1.5 miles as quickly as possible, avoid running. Maintain the same pace throughout.
   • Record the time in minutes and seconds.
   • Immediately after stopping, measure heart rate for 15 seconds and multiply by 4 to calculate beats per minute (bpm).
3. Formula:
   • VO₂max (mL/kg/min) = 132.853 - (0.0769 × weight in kg) - (0.3877 × age) + (6.315 × gender*) - (3.2649 × time in minutes) - (0.1565 × heart rate).  
     • * Use 1 for males and 0 for females in the gender variable.

Muscular Fitness

Muscular fitness encompasses both muscular strength—the maximum force a muscle can exert—and muscular endurance, the ability of a muscle to sustain repeated contractions over time. Assessing muscular fitness helps identify strengths and weaknesses, set fitness goals, and monitor progress. Below are practical methods for estimating muscular strength and endurance using minimal equipment.

Estimating Muscular Strength: 1-RM (One-Repetition Maximum)

The one-repetition maximum (1-RM) represents the heaviest weight you can lift for a single repetition. Because directly testing 1-RM can be challenging and potentially unsafe without proper supervision, you can estimate it using the Brzycki equation based on submaximal effort.

Procedure:

1. Choose an exercise (e.g., bench press or leg press).
2. Warm up with a light weight for 8–10 repetitions.
3. Select a weight you can lift for 3–10 repetitions.
4. Perform the exercise with proper form until you reach fatigue, ensuring safety and spotter assistance as needed.
5. If you successfully completed 10 repetitions or more, rest for 2 minutes, increase the weight by 5-10 lbs, and repeat step four. Do this until you cannot complete 10 repetitions with proper form.
6. Record the weight lifted and the number of repetitions completed.

Brzycki Equation:

• Estimated 1-RM (lbs)= Weight lifted (lbs)​/[1.0278−(0.0278×Number of reps)]

Example: If you lifted 100 lbs for 8 reps, your estimated 1-RM is:

• 1-RM=1.0278−(0.0278×8)100​=122.5lbs

Assessing Muscular Endurance

Muscular endurance can be tested using simple bodyweight or light-resistance exercises. Below are two common tests:

Push-Up Test (Upper Body Endurance):

• Procedure:
  1. Begin in a standard push-up position (or modify by placing knees on the floor).
  2. Lower your body until your elbows form a 90-degree angle, then return to the starting position.
  3. Perform as many push-ups as possible without pausing, stopping when you can no longer maintain form.

Flexibility

Flexibility assesses the range of motion of the joints. Because Flexibility is joint-specific it is important to assess the flexibility of each joint independently. 

Sit-and-Reach Test

This test measures hamstring and lower back flexibility.

1. Equipment: Ruler or yardstick.
2. Procedure:
   • Sit on the floor with legs straight, feet against a flat surface, and a ruler placed between the legs.
   • Reach forward as far as possible, keeping knees straight, and hold for 1–2 seconds.
   • Record the distance reached beyond the toes (or the deficit if unable to reach the toes).

Range of Motion (ROM) Tests

Use a smartphone leveling app to measure joint angles.

1. Choose a joint (e.g., shoulder, hip, knee).
2. Position the smartphone at the joint axis and measure ROM as you move the limb through its range.
3. Compare measurements to normative data.