Determining Cardiorespiratory Fitness With Precision: Compendium of Findings From the FRIEND Registry☆
Section snippets
Current methods for CRF assessment and interpretation
Understanding the factors that influence differences in CRF is important. Data from the HERITAGE study suggested that heritable factors, after adjusting for age and sex, were associated with ~50% of the variation in CRF in adults.9 Physical activity (PA), especially in the form of exercise training (ET), is the key HL behavior that can modify an individual's CRF.10., 11., 12. Accordingly, international public health statements strongly recommend regular PA worldwide.13 However, it is important
Value of CPX-derived CRF as the standard
Until the 1980s, exercise capacity was generally expressed as an estimated value based on maximal work rate achieved on a treadmill or cycle ergometer. The CPX method was generally limited to the domain of research physiologists and pulmonary medicine. The concept that estimated exercise capacity was an important marker of risk was demonstrated in the seminal Coronary Artery Surgery Studies (CASS) conducted in the late 1970s and early 1980s.29 The CASS investigators observed that among patients
Establishment and the importance of FRIEND
Along with the recognition of the value of CRF in recent years has come a need to develop ways to incorporate CRF into clinical, public health, and research settings. This need was recognized in a 2013 policy statement by the AHA entitled, “The Importance of Cardiorespiratory Fitness in the United States: The Need for a National Registry”.3 This scientific statement was part of an initiative to develop a national registry termed “Fitness Registry and the Importance of Exercise: A National Data
Reference standards from the FRIEND registry
The FRIEND registry provided an ideal opportunity to improve upon existing reference standards for CRF.55 The FRIEND data has advantages over previous efforts addressing this issue, including the fact that it overcomes many of the shortcomings cited in the Paap and Takken review,46 the American Thoracic Society Guidelines,21 and the AHA Scientific Statement on CPX.17 The FRIEND registry includes a large and diverse sample of healthy men and women in the US whose exercise tests met objectively
Conclusions
CRF is now considered a vital sign. As described in the current review, there is a need to improve the precision by which CRF is assessed and used to evaluate current health status and future risk. Moreover, efforts by FRIEND have helped to advance the precision of CRF prediction and normative values. As these efforts continue, the information obtained from a CRF assessment will become even more valuable to health professionals who are charged with optimizing outcomes for individuals under
Statement of conflict of interest
None of the authors have any conflicts of interests with regard to this publication.
Disclosures
L. Kaminsky serves as a Scientific Advisor for ENDO Medical, Inc.
Acknowledgement
The authors thank all the clinics and laboratories that have provided data for the FRIEND registry.
References (64)
- et al.
Preventing bad and expensive things from happening by taking the healthy living polypill: everyone needs this medicine
Mayo Clin Proc
(2017) - et al.
Healthy living: the universal and timeless medicine for healthspan
Prog Cardiovasc Dis
(2017) - et al.
Association between cardiorespiratory fitness and health care costs: the veterans exercise testing study
Mayo Clin Proc
(2018) - et al.
Taking physical activity, exercise, and fitness to a higher level
Prog Cardiovasc Dis
(2017) - et al.
Epidemiology of physical activity and exercise training in the United States
Prog Cardiovasc Dis
(2017) - et al.
High intensity interval training for maximizing health outcomes
Prog Cardiovasc Dis
(2017) - et al.
Promoting physical activity and exercise: JACC health promotion series
J Am Coll Cardiol
(2018) - et al.
Separate effects of intensity and amount of exercise on interindividual cardiorespiratory fitness response
Mayo Clin Proc
(2015) - et al.
Fitness versus physical activity patterns in predicting mortality in men
Am J Med
(2004) New American Heart Association/American College of Cardiology Guidelines on cardiovascular risk: when will fitness get the recognition it deserves?
Mayo Clin Proc
(2014)
Global fitness levels: findings from a web-based surveillance report
Prog Cardiovasc Dis
Estimated cardiorespiratory fitness assessment as a patient vital sign
Mayo Clin Proc
Impact of cardiorespiratory fitness on all-cause and disease-specific mortality: advances since 2009
Prog Cardiovasc Dis
Prognostic importance of a clinical profile and exercise test in medically treated patients with coronary artery disease
J Am Coll Cardiol
Prediction of atherosclerotic cardiovascular death in men using a prognostic score
Am J Cardiol
Clinical and exercise test markers of prognosis in patients with stable coronary artery disease
Curr Probl Cardiol
Errors in predicting functional capacity for postmyocardial infarction patients using a modified Bruce protocol
Am Heart J
The reproducibility of hemodynamic, electrocardiographic, and gas exchange data during treadmill exercise in patients with stable angina pectoris
Chest
Factors influencing estimated oxygen uptake during exercise testing soon after myocardial infarction
Am J Cardiol
Repeat treadmill exercise testing: variability of results in patients with angina pectoris
Am Heart J
Cardiopulmonary exercise testing in heart failure
Curr Probl Cardiol
Cardiopulmonary exercise testing in heart failure
J Am Coll Cardiol
Survival of the fittest-promoting fitness throughout the life span
Mayo Clin Proc
Quantification of cardiorespiratory fitness in healthy nonobese and obese men and women
Chest
Reference standards for cardiorespiratory fitness measured with cardiopulmonary exercise testing: data from the Fitness Registry and the Importance of Exercise National Database
Mayo Clin Proc
Reference values for cardiorespiratory response and fitness on the treadmill in a 20- to 85-year-old population
Chest
Reference standards for cardiorespiratory fitness measured with cardiopulmonary exercise testing using cycle ergometry: data from the Fitness Registry and the Importance of Exercise National Database (FRIEND) registry
Mayo Clin Proc
Reference equation for normal standards for VO2 max: analysis from the Fitness Registry and the Importance of Exercise National Database (FRIEND registry)
Prog Cardiovasc Dis
Importance of assessing cardiorespiratory fitness in clinical practice: a case for fitness as a clinical vital sign
Circulation
The importance of cardiorespiratory fitness in the United States: the need for a national registry: a policy statement from the American Heart Association
Circulation
Clinical recommendations for cardiopulmonary exercise testing data assessment in specific patient populations
Circulation
Exercise standards for testing and training: a scientific statement from the American Heart Association
Circulation
Cited by (38)
Global status of cardiorespiratory fitness and physical activity – Are we improving or getting worse?
2024, Progress in Cardiovascular Diseases2023 update: The importance of cardiorespiratory fitness in the United States
2024, Progress in Cardiovascular DiseasesAn Evolving Approach to Assessing Cardiorespiratory Fitness, Muscle Function and Bone and Joint Health in the COVID-19 Era
2022, Current Problems in CardiologyPeak oxygen pulse and mortality risk in healthy women and men: The Ball State Adult Fitness Longitudinal Lifestyle Study (BALL ST)
2021, Progress in Cardiovascular DiseasesCitation Excerpt :Descriptive statistics were performed to summarize baseline characteristics of the participants. Fitness percentiles were determined based on relative VO2peak (ml·kg−1·min−1) using the Fitness Registry and the Importance of Exercise National Database (FRIEND),26,27 which provides age- and sex-specific VO2peak reference values for adults in the United States. To test for differences between sexes and mortality status (survivor vs. deceased), independent samples t-tests and chi square goodness of fit tests were performed when appropriate.
Two-minute exercise testing is sufficient to estimate maximal cardiorespiratory fitness in people with epilepsy
2021, Epilepsy and BehaviorCitation Excerpt :min−1) and detection bias (Spearman coefficient p = 0.13) from our estimates, we were able to correctly assign all participants to the age- and sex- specific CRF percentile [21]. CRF is inversely associated with all-cause mortality [7] and powerfully predicts risk for other adverse events across the spectrum of health and disease [30]. As a result, reference values were created so a more precise evaluation of someone’s CRF could be provided [21].
Reference values for aerobic capacity estimated by cardiopulmonary exercise test on a cycle ergometer in a healthy Greek population
2021, Hellenic Journal of CardiologyCitation Excerpt :As AC and subsequent health risk estimation varies according to age, sex, and population, it is very important to have accurate CPET reference values.6 Recently, the American Heart Association (AHA) called for the development of a national AC registry, named Fitness Registry and the Importance of Exercise National Database (FRIEND), in apparently healthy individuals in USA, illustrating the recognized importance of accurately quantifying CRF in assessing an individual's overall health and risk for the development of future CV diseases and adverse events.12-15 Accordingly, normative AC values derived from small or larger cohorts of several ethnic populations worldwide have recently been published, thus demonstrating an increased recognition of this assessment in healthy individuals.16-21
- ☆
Statement of Conflict of Interest: see page 81.