How fit are you?  Most people reply to this question with “I’m pretty fit.”  However, how do you know how fit you really are?  Researchers at the University of Washington studied this by analyzing data from treadmill tests conducted on 1,978 adult men and women in the National Health and Nutrition Evaluation Survey (NHANES) that comprised a stratified sample of the entire United States.

Researchers calculated the VO2 max, or maximum aerobic capacity, for each subject and used the data to develop national norms for cardiovascular fitness for adults ages 20-49.  The norms were divided into three fitness categories:

1. Low fit – having an aerobic capacity equal to the least fit 20% of the population for that age group and gender.
2. Moderately fit – having an average aerobic capacity equal to 20-59% of the population for that age group and gender.
3. High fit – having an aerobic capacity equal to the most fit 60-100% of the population for each age group and gender, or above average.

Previous research was conducted by the Cooper Aerobic Research Center that used similar fitness ratings.  The results of this research include:

• The low fit group has the highest mortality rates.
• The high fit group had the lowest mortality rates
• The “moderate fit” group’s mortality rates were in between.
• Low fit men were 3.2 times more likely to die during the 10-year follow-up than fit men.
• Low fit women were 5.3 times more likely to die during the 10-year study than high fit women.
• The biggest drop in mortality was between those in the low fit to moderate fit; this indicates that even moderate exercise done regularly had a strong protective effect on health.

Click here to assess your aerobic capacity

Aerobic Capacity Norms:

Fitness Category	Males VO2 max (ml/min/kg)	Females VO2 max (ml/min/kg)
Ages 20-29
Low fit	<37.1	<30.6
Moderate fit	37.1 – 44.2	30.6 – 36.6
High fit	44.3 +	36.7 +
Ages 30-39
Low fit	<35.3	<28.7
Moderate fit	35.3 – 42.4	28.7 – 34.6
High fit	42.5 +	34.7 +
Ages 40-49
Low fit	<33.0	<26.5
Moderate fit	33.0 – 39.9	26.5 – 32.3
High fit	40.0 +	32.4 +
Ages 50-59
Low fit	<31.4	<25.1
Moderate fit	31.4 – 39.3	25.1 - 31.3
High fit	39.4 +	31.4 +
Ages 60+
Low fit	<28.3	<21.9
Moderate fit	28.3 – 36.1	21.9 – 28.2
High fit	36.2 +	28.3 +

 

The Bottom Line:

Keep in mind that being in the moderately fit or average fitness level category is not necessarily desirable; it is important to consider that these norms are based on a population that is largely sedentary.  If you want to improve your longevity, your best odds are to stay in the high fit group.

• Regular exercise is critical for strong bones.  This is especially critical for adolescents, teens, and young adults.
• Participating in activity that builds stronger bones during youth continues even after becoming less active for 5 years.
• Staying active throughout your life is the best for maintaining bone health.

Sources:  Sanders and Duncan (April 2006). Population-Based Reference Standards for Cardiovascular Fitness among U.S. Adults: NHANES 1999-2000 and 2001-2002. Medicine & Science in Sports & Exercise, 38:701-7; Blair, et al. (1989).  Physical fitness and all-cause mortality. A prospective study of healthy men and women. Journal of the American Medical Association, 262:2395-2401; Determining Aerobic Capacity (2006), Wellsource, Inc.