In large population studies, comparisons of physical activity, self-rated fitness, and measured aerobic fitness are seldom reported. Measuring aerobic fitness is time-consuming and expensive, thus alternative methods are needed.
To investigate the recently established Polar Fitness Test (PFT) as a method to predict maximal oxygen uptake (VO2max, a measure of maximal aerobic power), to assess distribution of predicted VO2max by gender and age, and to compare predictions to self-reported leisure time physical activity and self-rated fitness level in a large Finnish population sample.
The study population comprised 5979 men and women aged 25 to 74 years who participated in the National FINRISK Study. Subjects filled in standardized questionnaires assessing self-rated fitness level and total, conditioning, commuting, and non-conditioning leisure time physical activity. The PFT was performed by a trained nurse at the study site and was based on resting heart rate measurements, gender, age, height, weight, and self-reported physical activity. Healthy individuals and those with a self-reported cardiovascular disease were analyzed separately.
The mean predicted VO2max was 38.1 and 35.1 ml/kg/min in healthy men and women, respectively. In both genders, predicted VO2max declined significantly by age. Individuals with cardiovascular disease had lower VO2max predictions than healthy persons. Healthy men reported total leisure time physical activity slightly less than healthy women. Self-rated fitness level and conditioning and commuting leisure time physical activity were independently associated with predicted VO2max, while no correlation between non-conditioning leisure time physical activity and predicted aerobic fitness was found.
PFT was a feasible method to predict aerobic fitness in a large population study and was related both to self-rated fitness and self-reported physical activity. Aerobic fitness was associated with conditioning and commuting physical activity, but not with non-conditioning physical activity.