18 Cardiorespiratory Fitness
The Physical Activity Guidelines for Americans recommend that adults get at least 150 minutes of moderate-intensity aerobic physical activity or 75 minutes of vigorous-intensity physical activity or an equivalent combination each week. Although, the overarching recommendation is to aim for the recommended activity level but be as active as you are able.
The table below provides the American College of Sports Medicine (ACSM) recommendations to improve and maintain cardiorespiratory fitness.
FITT Principle | Moderate Intensity Exercise | Vigorous Intensity Exercise |
Combined | Weight Loss |
Frequency | ≥ 5×/week | ≥ 3×/week | 3–5×/week | 5–7×/week |
Intensity | 50–60% HRR,
60–75% MHR |
≥ 60% HRR | Moderate or Vigorous | Moderate |
Time | ≥ 30 min/day | ≥ 20 min/day | ≥ 20 min/day | 50–60 min/day |
Type | Aerobic | Aerobic | Aerobic | Aerobic |
Volume: | ≥ 150 min/week | ≥ 75 min/week | ≥ 75 min/week | 300 min/week |
Types of Activities to Improve Cardiorespiratory Fitness
ACSM places cardiorespiratory activities into three groups categorized according to skill demands as outlined in the chart below. Skiing and snowboarding would fall into Group 3.
Skill Demands | Cardiorespiratory Activities | Training Effect on Cardiorespiratory Fitness | |
Group 1 | Require very little skill and provide a constant intensity level. | Jogging, running, walking,
cardio equipment |
Generally, the most ideal for maintenance and improvement of cardiorespiratory fitness. |
Group 2 | Require more skill than Group 1 activities. The intensity is dependent on the skill of the individual. | Swimming, aerobic dance, cycling on a real bicycle (not a stationary bike), skating, skiing | Can be as effective as Group 1 activities for maintenance/improvement of cardiorespiratory fitness provided that the individual exercising is skilled enough in that activity to maintain the minimum exercise intensity. |
Group 3 | Incorporates a large variety of skill requirements and intensity levels. Generally, more fun than activities in Groups 1 and 2 and are good ways to make cardiorespiratory fitness more enjoyable. | Basketball, soccer, racket sports | Mostly effective for maintenance of cardiorespiratory fitness rather than improvement since there is less control over the intensity levels. |