Chronic use of Antihypertensive Medications and Peak Exercise Blood Pressure in Adult Men and Women from the BALL ST Cohort.

PURPOSE: To determine if individuals chronically (>1 year) prescribed antihypertensive medications have a normal BP response to peak exercise compared to unmedicated individuals. METHODS: Participants included 2,555 adults from the Ball State Adult Fitness Longitudinal Lifestyle STudy cohort who performed a peak treadmill exercise test. Participants were divided into groups by sex and antihypertensive medication status. Individuals prescribed antihypertensive medications for >1 year were included. Exaggerated and blunted SBP within each group was categorized using the Fitness Registry and the Importance of Exercise: A National Database (FRIEND) and absolute criteria as noted by the Amercian Heart Association. RESULTS: The unmedicated group had a greater prevalence (p < 0.05) of blunted SBP responses, whereas the medicated group had a higher prevalence (p < 0.05) of exaggerated SBP responses using both the FRIEND and absolute criteria. Peak SBP was higher (p < 0.01) in medicated compared to unmedicated participants in the overall cohort when controlling for age and sex, but not after controlling for resting SBP (p = 0.613), risk factors (p = 0.104), or cardiorespiratory fitness (p = 0.191). When men and women were assessed independently, peak SBP remained higher in the medicated women after controlling for age and resting SBP (p = 0.039), but not for men (p = 0.311). Individuals on beta-blockers had a higher peak SBP even after controlling for age, sex, risk factors and cardiorespiratory fitness (p = 0.022). CONCLUSIONS: Individuals on antihypertensive medications have a higher peak SBP response to exercise. Given the prognostic value of exaggerated peak SBP, control of exercise BP should be considered in routine BP assessment and in the treatment of hypertension.

Oxygen Uptake Efficiency Slope as a Predictor of Mortality Risk: THE BALL STATE ADULT FITNESS LONGITUDINAL LIFESTYLE STUDY (BALL ST).

PURPOSE: Oxygen uptake efficiency slope (OUES), defined as the slope of the linear relationship between oxygen uptake and the semilog transformed ventilation rate measured during an incremental exercise test, may have prognostic utility. The objective of this investigation was to examine the relationship between assessments of OUES and all-cause mortality in a cohort of apparently healthy adults. METHODS: The sample included 2220 apparently healthy adults (48% females) with a mean age of 44.7 ± 12.9 yr who performed cardiopulmonary exercise testing. The OUES was calculated from the entire test, using data from the initial 50% (OUES 50 ) and 75% (OUES 75 ) of test time, and normalized to body surface area. Cox proportional hazard models assessed the relationship between measures of OUES and mortality. Prognostic peak oxygen uptake (V˙ o2peak ) and OUES models were compared using the concordance index. RESULTS: There were 310 deaths (29% females) over a follow-up period of 19.8 ± 11.1 yr. For males, OUES, OUES 75 , and normalized OUES had an inverse association with mortality, even after adjusting for traditional risk factors ( P < .05). For females, only the unadjusted OUES, OUES 75 , and normalized OUES models were associated with mortality ( P < .05). The concordance index values indicated that unadjusted OUES 50 and OUES 75 models had lower discrimination than the unadjusted OUES and V˙ o2peak models ( P < .05). Furthermore, OUES did not complement the fully adjusted V˙ o2peak model ( P ≥ .32). CONCLUSIONS: Assessments of OUES are related to all-cause mortality in males but not in females. These findings suggest that OUES can have prognostic utility in apparently healthy males. Moreover, submaximal determinations of OUES could have value when measuring V˙ o2peak is not feasible.

Cardiorespiratory Optimal Point Is a Submaximal Exercise Test Variable and a Predictor of Mortality Risk: THE BALL STATE ADULT FITNESS LONGITUDINAL LIFESTYLE STUDY (BALL ST).

PURPOSE: The cardiorespiratory optimal point (COP) is the minimum ventilatory equivalent for oxygen. The COP can be determined during a submaximal incremental exercise test. Reflecting the optimal interaction between the respiratory and cardiovascular systems, COP may have prognostic utility. The aim of this investigation was to determine the relationship between COP and all-cause mortality in a cohort of apparently healthy adults. METHODS: The sample included 3160 apparently healthy adults (46% females) with a mean age of 44.0 ± 12.5 yr who performed a cardiopulmonary exercise test. Cox proportional hazards models were performed to assess the relationship between COP and mortality risk. Prognostic peak oxygen uptake (V˙ o2peak ) and COP models were compared using the concordance index. RESULTS: There were 558 deaths (31% females) over a follow-up period of 23.0 ± 11.9 yr. For males, all Cox proportional hazards models, including the model adjusted for traditional risk factors and V˙ o2peak , had a positive association with risk for mortality ( P < .05). For females, only the unadjusted COP model was associated with risk for mortality ( P < .05). The concordance index values indicated that unadjusted COP models had lower discrimination compared with unadjusted V˙ o2peak models ( P < .05) and V˙ o2peak did not complement COP models ( P ≥ .13). CONCLUSIONS: Cardiorespiratory optimal point is related to all-cause mortality in males but not females. These findings suggest that a determination of COP can have prognostic utility in apparently healthy males aged 18-85 yr, which may be relevant when a maximal exercise test is not feasible or desirable.

Change in Metabolic Syndrome and Cardiorespiratory Fitness Following Exercise Training - The Ball State Adult Fitness Longitudinal Lifestyle Study (BALL ST).

Purpose: To evaluate how the changes in directly measured cardiorespiratory fitness (CRF) relate to the changes in metabolic syndrome (MetS) status following 4-6 months of exercise training. Methods: Maximal cardiopulmonary exercise (CPX) tests and MetS risk factors were analyzed prospectively from 336 adults (46% women) aged 45.8 ± 10.9 years. MetS was defined according to the National Cholesterol Education Program-Adult Treatment Panel III criteria, as updated by the American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI). Pearson correlations, chi-squares, and dependent 2-tail t-tests were used to assess the relationship between the change in CRF and the change in MetS risk factors, overall number of MetS risk factors, and a MetS severity score following 4-6 months of participation in a self-referred, community-based exercise program. Results: Overall prevalence of MetS decreased from 23% to 14% following the exercise program (P < 0.05), while CRF improved 15% (4.7 ± 8.4 mL/kg/min, P < 0.05). Following exercise training, the number of positive risk factors declined from 1.4 ± 1.3 to 1.2 ± 1.2 in the overall cohort (P < 0.05). The change in CRF was inversely related to the change in the overall number of MetS risk factors (r = -0.22; P < 0.05) and the MetS severity score (r = -0.28; p < 0.05). Conclusion: This observational cohort study indicates an inverse relationship between the change in CRF and the change in MetS severity following exercise training. These results suggest that participation in a community-based exercise program yields significant improvements in CRF, MetS risk factors, the prevalence of the binary MetS, and the MetS severity score. Improvement in CRF through exercise training should be a primary prevention strategy for MetS.

Cardiopulmonary Exercise Responses in Individuals with Metabolic Syndrome: The Ball State Adult Fitness Longitudinal Lifestyle Study.

Background: The association between cardiorespiratory fitness (CRF) and metabolic syndrome (MetSyn) is well established. Additional variables derived from cardiopulmonary exercise testing (CPET) have shown prognostic value in some chronic diseases, however, there is limited information on how cardiopulmonary responses to exercise may be altered in individuals with MetSyn. Thus, the purpose of this study was to examine the association between cardiopulmonary variables derived from CPET and MetSyn. Methods: A cohort of 3181 participants (1714 men, 1467 women), aged 20-79 years, completed CPET and metabolic risk factor assessment between January 1, 1971, and November 1, 2020. Cardiopulmonary variables assessed included CRF defined as the maximum volume of oxygen uptake (VO2max), ventilatory threshold (VO2@VT), oxygen uptake efficiency slope (OUES), the ratio of ventilation to VO2 at peak exercise (peak VE/VO2) and the VE/VCO2slope. MetSyn was defined using the National Cholesterol Education Program/Adult Treatment Panel. Results: VO2max, VO2@VT, and OUES were lower (P < 0.001) and VE/VCO2slope was higher (P < 0.001) in individuals with MetSyn (n = 774), whereas no difference between groups existed for peak VE/VO2. Logistic regression analysis revealed that VO2max [0.91, 0.89-0.93; odds ratio (OR), 95% confidence interval (CI)], VO2@VT (0.91, 0.87-0.95; OR, 95% CI), OUES (0.32, 0.20-0.52; OR, 95% CI), and VE/VCO2slope (1.03, 1.01-1.05 OR, 95% CI) were all associated with the presence of MetSyn (P ≤ 0.001). Conclusion: These results indicate that MetSyn is associated with altered cardiopulomary function that may provide insight into the underlying pathophysiology of MetSyn.

Associations Between Active Commuting and Cardiovascular Disease in the United States.

BACKGROUND: Active commuting is inversely related with cardiovascular disease (CVD) risk factors yet associations with CVD prevalence in the US population are unknown. METHODS: Aggregate data from national surveys conducted in 2017 provided state-level percentages of adults who have/had coronary heart disease, myocardial infarction, and stroke, and who actively commuted to work. Associations between active commuting and CVD prevalence rates were assessed using Pearson correlations and generalized additive models controlling for covariates. RESULTS: Significant correlations were observed between active commuting and all CVD rates (r range = -.31 to -.47; P < .05). The generalized additive model analyses for active commuting (walking, cycling, or public transport) in all adults found no relationships with CVD rates; however, a significant curvilinear association was observed for stroke within men. The generalized additive model curves when examining commuting via walking or cycling in all adults demonstrated nuanced, generally negative linear or curvilinear associations between coronary heart disease, myocardial infarction, and stroke. CONCLUSION: Significant negative correlations were observed between active commuting and prevalence rates of coronary heart disease, myocardial infarction, and stroke. Controlling for covariates influenced these associations and highlights the need for future research to explore the potential of active commuting modes to reduce CVD in the United States.

Comparison of non-exercise cardiorespiratory fitness prediction equations in apparently healthy adults.

AIMS: A recent scientific statement suggests clinicians should routinely assess cardiorespiratory fitness using at least non-exercise prediction equations. However, no study has comprehensively compared the many non-exercise cardiorespiratory fitness prediction equations to directly-measured cardiorespiratory fitness using data from a single cohort. Our purpose was to compare the accuracy of non-exercise prediction equations to directly-measured cardiorespiratory fitness and evaluate their ability to classify an individual's cardiorespiratory fitness. METHODS: The sample included 2529 tests from apparently healthy adults (42% female, aged 45.4 ± 13.1 years (mean±standard deviation). Estimated cardiorespiratory fitness from 28 distinct non-exercise prediction equations was compared with directly-measured cardiorespiratory fitness, determined from a cardiopulmonary exercise test. Analysis included the Benjamini-Hochberg procedure to compare estimated cardiorespiratory fitness with directly-measured cardiorespiratory fitness, Pearson product moment correlations, standard error of estimate values, and the percentage of participants correctly placed into three fitness categories. RESULTS: All of the estimated cardiorespiratory fitness values from the equations were correlated to directly measured cardiorespiratory fitness (p < 0.001) although the R2 values ranged from 0.25-0.70 and the estimated cardiorespiratory fitness values from 27 out of 28 equations were statistically different compared with directly-measured cardiorespiratory fitness. The range of standard error of estimate values was 4.1-6.2 ml·kg-1·min-1. On average, only 52% of participants were correctly classified into the three fitness categories when using estimated cardiorespiratory fitness. CONCLUSION: Differences exist between non-exercise prediction equations, which influences the accuracy of estimated cardiorespiratory fitness. The present analysis can assist researchers and clinicians with choosing a non-exercise prediction equation appropriate for epidemiological or population research. However, the error and misclassification associated with estimated cardiorespiratory fitness suggests future research is needed on the clinical utility of estimated cardiorespiratory fitness.

Healthy Vascular Aging Is Associated With Higher Cardiorespiratory Fitness.

BACKGROUND: Healthy vascular aging (HVA) and cardiorespiratory fitness (CRF) are each independently associated with lower cardiovascular disease-related mortality. It is unknown, however, whether the CRF-related reductions in cardiovascular disease risk are related to HVA. We hypothesized that HVA would be associated with higher CRF in men and women from the Ball State Adult Fitness Longitudinal Lifestyle STudy (BALL ST). METHODS: Apparently healthy men and women ≥50 yr of age from the BALL ST cohort (n = 101) who underwent a maximal cardiopulmonary exercise test to assess CRF (V˙O2peak) were included in the study. Participants were divided into either HVA, defined as brachial systolic blood pressure <140/90 mm Hg without taking medications and carotid-femoral pulse wave velocity <7.6 m/sec, or no HVA for subjects with SBP >140/90 mm Hg and/or PWV >7.6 m/sec. RESULTS: Participants with HVA had a higher age- and sex-adjusted CRF percentile (62 ± 5 vs 47 ± 3, P < .05), with women having a greater prevalence of HVA than men (36% vs 15%, P < .05). Both carotid-femoral pulse wave velocity (r =-0.27, P < .05) and brachial systolic blood pressure (r =-0.23, P < .05) were independently and inversely associated with CRF for the entire cohort. Men and women with HVA were younger having a lower body fat percentage and higher low-density lipoprotein cholesterol (P < .05, all). CONCLUSIONS: These data demonstrate that HVA is associated with higher CRF, which may partially explain the preventative cardioprotective effects of CRF.

Accuracy of Exercise-based Equations for Estimating Cardiorespiratory Fitness.

Equations are often used to predict cardiorespiratory fitness (CRF) from submaximal or maximal exercise tests. However, no study has comprehensively compared these exercise-based equations with directly measured CRF using data from a single, large cohort. PURPOSE: This study aimed to compare the accuracy of exercise-based prediction equations with directly measured CRF and evaluate their ability to classify an individual's CRF. METHODS: The sample included 4871 tests from apparently healthy adults (38% female, age 44.4 ± 12.3 yr (mean ± SD)). Estimated CRF (eCRF) was determined from 2 nonexercise equations, 3 submaximal exercise equations, and 10 maximal exercise equations; all eCRF calculations were then compared with directly measured CRF, determined from a cardiopulmonary exercise test. Analysis included Pearson product-moment correlations, standard error of estimate values, intraclass correlation coefficients, Cohen κ coefficients, and the Benjamini-Hochberg procedure to compare eCRF with directly measured CRF. RESULTS: All eCRF values from the prediction equations were associated with directly measured CRF (P < 0.01), with intraclass correlation coefficient estimates ranging from 0.07 to 0.89. Although significant agreement was found when using eCRF to categorize participants into fitness tertiles, submaximal exercise equations correctly classified an average of only 51% (range, 37%-58%) and maximal exercise equations correctly classified an average of only 59% (range, 43%-76%). CONCLUSIONS: Despite significant associations between exercise-based prediction equations and directly measured CRF, the equations had a low degree of accuracy in categorizing participants into fitness tertiles, a key requirement when stratifying risk within a clinical setting. The present analysis highlights the limited accuracy of exercise-based determinations of eCRF and suggests the need to include cardiopulmonary measures with maximal exercise to accurately assess CRF within a clinical setting.

Trends in cardiorespiratory fitness among apparently healthy adults from the Ball State Adult Fitness Longitudinal Lifestyle STudy (BALL ST) cohort from 1970-2019.

INTRODUCTION: Cardiorespiratory fitness (CRF) is a strong independent predictor of cardiovascular disease (CVD) and CVD mortality. However, little is known in regards to how CRF has trended in apparently healthy adults over the past several decades. PURPOSE: To analyze trends in CRF and CVD risk factors over the last 50 years in a population of apparently healthy adult men and women. METHODS: Participants were 4,214 apparently healthy adults (2,390 men and 1,824 women) from the Ball State Adult Fitness Longitudinal Lifestyle STudy (BALL ST) that performed maximal cardiopulmonary exercise testing between 1970-2019 for the assessment of CRF defined as VO2max (ml/kg/min). Participants were self-referred either to a community-based exercise program, fitness testing, or were research subjects in exercise related studies and were placed into groups by decade based on testing date. RESULTS: CRF showed a general trend to decline (P<0.05) from the 1970s to the 2000s with an increase (P<0.05) from the 2000s to the 2010s for both men and women. This pattern persisted for age and sex-adjusted CRF level, determined by Fitness Registry and the Importance of Exercise: A National Data Base (FRIEND). For both women and men, CRF across the decades was associated (P<0.05) with the prevalence of physical inactivity, smoking, obesity, dyslipidemia and hypertension, and with diabetes in men only. CONCLUSION: CRF declined from 1970 through the 2000s in a cohort of apparently healthy men and women which was associated with worsening CVD risk profiles. However, the decline in CRF was attenuated over the past decade which may have a positive impact on future CVD in the population. Promoting physical activity to increase CRF should be a primary aspect of CVD prevention programs.

Accuracy of Nonexercise Prediction Equations for Assessing Longitudinal Changes to Cardiorespiratory Fitness in Apparently Healthy Adults: BALL ST Cohort.

Background Repeated assessment of cardiorespiratory fitness (CRF) improves mortality risk predictions in apparently healthy adults. Accordingly, the American Heart Association suggests routine clinical assessment of CRF using, at a minimum, nonexercise prediction equations. However, the accuracy of nonexercise prediction equations over time is unknown. Therefore, we compared the ability of nonexercise prediction equations to detect changes in directly measured CRF. Methods and Results The sample included 987 apparently healthy adults from the BALL ST (Ball State Adult Fitness Longitudinal Lifestyle Study) cohort (33% women; average age, 43.1±10.4 years) who completed 2 cardiopulmonary exercise tests ≥3 months apart (3.2±5.4 years of follow-up). The change in estimated CRF (eCRF) from 27 distinct nonexercise prediction equations was compared with the change in directly measured CRF. Analysis included Pearson product moment correlations, SEE values, intraclass correlation coefficient values, Cohen's κ coefficients, γ coefficients, and the Benjamini-Hochberg procedure to compare eCRF with directly measured CRF. The change in eCRF from 26 of 27 equations was significantly associated to the change in directly measured CRF (P<0.001), with intraclass correlation coefficient values ranging from 0.06 to 0.63. For 16 of the 27 equations, the change in eCRF was significantly different from the change in directly measured CRF. The median percentage of participants correctly classified as having increased, decreased, or no change in CRF was 56% (range, 39%-61%). Conclusions Variability was observed in the accuracy between nonexercise prediction equations and the ability of equations to detect changes in CRF. Considering the appreciable error that prediction equations had with detecting even directional changes in CRF, these results suggest eCRF may have limited clinical utility.

Cardiorespiratory Fitness Normalized to Fat-Free Mass and Mortality Risk.

PURPOSE: Cardiorespiratory fitness (CRF) is known to be directly related to fat-free mass (FFM), therefore, it has been suggested that normalizing CRF to FFM (V˙O2peakFFM) may be the most accurate expression of CRF as related to exercise performance and cardiorespiratory function. However, the influence of V˙O2peakFFM (mL·kg FFM·min) on predicting mortality has been largely unexplored. This study aimed to primarily assess the relationship between V˙O2peakFFM and all-cause and disease-specific mortality risk in apparently healthy adults. Further, this study sought to compare the predictive ability of V˙O2peakFFM to V˙O2peak normalized to total body weight (V˙O2peakTBW) for mortality outcomes. METHODS: Participants included 2905 adults (1555 men, 1350 women) who completed a cardiopulmonary exercise test between 1970 and 2016 to determine CRF. Body composition was assessed using the skinfold method to estimate FFM. Cardiorespiratory fitness was expressed as V˙O2peakTBW and V˙O2peakFFM. Participants were followed for 19.0 ± 11.7 yr after their cardiopulmonary exercise test for mortality outcomes. Cox-proportional hazard models were performed to determine the relationship of V˙O2peakFFM with mortality outcomes. Parameter estimates were assessed to compare the predictive ability of CRF expressed as V˙O2peakTBW and V˙O2peakFFM. RESULTS: Overall, V˙O2peakFFM was inversely related to all-cause, cardiovascular disease, and cancer mortality, with a 16.2%, 8.4%, and 8.0% lower risk per 1 mL·kg FFM·min improvement, respectively (P < 0.01). Further, assessment of the parameter estimates showed V˙O2peakFFM to be a significantly stronger predictor of all-cause mortality than V˙O2peakTBW (parameter estimates, -0.49 vs -0.16). CONCLUSIONS: Body composition is an important factor when considering the relationship between CRF and mortality risk. Clinicians should consider normalizing CRF to FFM when feasible, because it will strengthen the predictive power of the measure.

The Influence of Change in Cardiorespiratory Fitness With Short-Term Exercise Training on Mortality Risk From The Ball State Adult Fitness Longitudinal Lifestyle Study.

OBJECTIVE: To assess the influence of changes in cardiorespiratory fitness (CRF) after exercise training on mortality risk in a cohort of self-referred, apparently healthy adults. PATIENTS AND METHODS: A total of 683 participants (404 men, 279 women; mean age: 42.7±11.0 y) underwent two maximal cardiopulmonary exercise tests (CPX) between March 20, 1970, and December 11, 2012, to assess CRF at baseline (CPX1) and post-exercise training (CPX2). Participants were followed for an average of 29.8±10.7 years after their CPX2. Cox proportional hazards models were performed to determine the relationship of CRF change with mortality, with change in CRF as a continuous variable, as well as a categorical variable. A Wald chi-square test was used to compare the coefficients estimating the relationship of peak oxygen consumption (VO2peak) at CPX1 with VO2peak measured at CPX2 with time until death for all-cause mortality. RESULTS: During the follow-up period there were 180 deaths. When assessed independently, there were 20% (95% CI, 10-49%) and 38% (95% CI, 7-66%) lower mortality risks per 1 metabolic equivalent improvement in CRF (P<.01) in men and women, respectively, after multivariable adjustment. Those that remained unfit had ∼2-fold higher risk for all-cause mortality compared with those that remained fit and CRF at CPX2 was a stronger predictor of all-cause mortality than at CPX1 (P=.02). CONCLUSION: Improving CRF through exercise training lowers mortality risk. Clinicians should encourage individuals to participate in exercise training to improve CRF to lower risk of mortality.

The Association between the Change in Directly Measured Cardiorespiratory Fitness across Time and Mortality Risk.

BACKGROUND: The relationship between cardiorespiratory fitness (CRF) and mortality risk has typically been assessed using a single measurement, though some evidence suggests the change in CRF over time influences risk. This evidence is predominantly based on studies using estimated CRF (CRFe). The strength of this relationship using change in directly measured CRF over time in apparently healthy men and women is not well understood. PURPOSE: To examine the association of change in CRF over time, measured using cardiopulmonary exercise testing (CPX), with all-cause and disease-specific mortality and to compare baseline and subsequent CRF measurements as predictors of all-cause mortality. METHODS: Participants included 833 apparently healthy men and women (42.9 ±â€¯10.8 years) who underwent two maximal CPXs, the second CPX being ≥1 year following the baseline assessment (mean 8.6 years, range 1.0 to 40.3 years). Participants were followed for up to 17.7 (SD 11.8) years for all-cause-, cardiovascular disease- (CVD), and cancer mortality. Cox-proportional hazard models were performed to determine the association between the change in CRF, computed as visit 1 (CPX1) peak oxygen consumption (VO2peak [mL·kg-1·min-1]) - visit 2 (CPX2) VO2peak, and mortality outcomes. A Wald-Chi square test of equality was used to compare the strength of CPX1 to CPX2 VO2peak in predicting mortality. RESULTS: During follow-up, 172 participants died. Overall, the change in CPX-CRF was inversely related to all-cause, CVD, and cancer mortality (p < 0.05). Each 1 mL·kg-1·min-1 increase was associated with a ~11, 15, and 16% (all p < 0.001) reduction in all-cause, CVD, and cancer mortality, respectively. The inverse relationship between CRF and all-cause mortality was significant (p < 0.05) when men and women were examined independently, after adjusting for years since first CPX, baseline VO2peak, and age. Further, the Wald Chi-square test of equality found CPX2 VO2peak to be a significantly stronger predictor of all-cause mortality than CPX1 VO2peak (p < 0.05). CONCLUSION: The change in CRF over time was inversely related to mortality outcomes, and mortality was better predicted by CRF measured at subsequent test than CPX1 CRF. These findings emphasize the importance of adopting lifestyle behaviors that promote CRF, as well as support the need for routine assessment of CRF in clinical practice to better assess risk.

Cardiorespiratory Fitness and Mortality in Healthy Men and Women.

BACKGROUND: There is a well-established inverse relationship between cardiorespiratory fitness (CRF) and mortality. However, this relationship has almost exclusively been studied using estimated CRF. OBJECTIVES: This study aimed to assess the association of directly measured CRF, obtained using cardiopulmonary exercise (CPX) testing with all-cause, cardiovascular disease (CVD), and cancer mortality in apparently healthy men and women. METHODS: Participants included 4,137 self-referred apparently healthy adults (2,326 men, 1,811 women; mean age: 42.8 ± 12.2 years) who underwent CPX testing to determine baseline CRF. Participants were followed for 24.2 ± 11.7 years (1.1 to 49.3 years) for mortality. Cox-proportional hazard models were performed to determine the relationship of CRF (ml·kg-1·min-1) and CRF level (low, moderate, and high) with mortality outcomes. RESULTS: During follow-up, 727 participants died (524 men, 203 women). CPX-derived CRF was inversely related to all-cause, CVD, and cancer mortality. Low CRF was associated with higher risk for all-cause (hazard ratio [HR]: 1.73; 95% confidence interval [CI]: 1.20 to 3.50), CVD (HR: 2.27; 95% CI: 1.20 to 3.49), and cancer (HR: 2.07; 95% CI: 1.18 to 3.36) mortality compared with high CRF. Further, each metabolic equivalent increment increase in CRF was associated with a 11.6%, 16.1%, and 14.0% reductions in all-cause, CVD, and cancer mortality, respectively. CONCLUSIONS: Given the prognostic ability of CPX-derived CRF for all-cause and disease-specific mortality outcomes, its use should be highly considered for apparently healthy populations as it may help to improve the efficacy of the individualized patient risk assessment and guide clinical decisions.

Cardiorespiratory Fitness Is Inversely Associated With Clustering of Metabolic Syndrome Risk Factors: The Ball State Adult Fitness Program Longitudinal Lifestyle Study.

OBJECTIVE: The focus of this study was the association between the metabolic syndrome (MetSyn) and cardiorespiratory fitness (CRF) defined as maximal oxygen uptake (VO2max). Although previous research has shown a relationship between MetSyn and CRF, most studies are based on less objective measures of CRF and different cardiometabolic risk factor thresholds from earlier guidelines. PARTICIPANTS AND METHODS: The metabolic markers included in the present study were central obesity, elevated plasma triglycerides, elevated fasting high-density lipoprotein cholesterol, impaired fasting plasma glucose, hypertension, or pharmacologic treatment for diagnosed hypertension, hypertriglyceridemia, low high-density lipoprotein cholesterol, or diabetes. A cohort of 3636 adults (1629 women, 2007 men; mean ± SD age, 44.7±12.3 years) completed CRF and metabolic risk factor assessment between January 1, 1971, and November 1, 2016. The CRF was defined as a measured VO2max from a cardiopulmonary exercise test on a treadmill, with a respiratory exchange ratio value of 1.0 or more. RESULTS: Prevalence of MetSyn (≥3 factors) was 26% (n=953) in the cohort, with men having a greater likelihood for MetSyn compared with women (P<.001). The difference in VO2max between those individuals with MetSyn and those without was approximately 2.3 (2.0-2.5) metabolic equivalents. Logistic regression analyses showed a significant inverse and graded association between quartiles of CRF and MetSyn for the group overall (P<.001), with odds ratios (95% CI) using the lowest fitness group as the referent group of 0.67 (0.55-0.81), 0.41 (0.34-0.51), and 0.10 (0.07-0.14) for VO2max (P<.001). The sex-specific odds ratios were 0.25 (0.18-0.34), 0.05 (0.02-0.10), and 0.02 (0.01-0.09) for women and 0.43 (0.31-0.59), 0.19 (0.14-0.27), and 0.03 (0.02-0.05) for men (P<.001). CONCLUSION: These results with current risk factor thresholds and a large number of women demonstrate that low VO2max is associated with MetSyn.

Maximal heart rate declines linearly with age independent of cardiorespiratory fitness levels.

There have been many conflicting observations between the linear or curvilinear decline in maximal heart rate (HRmax) with age. The aim of this study was to determine if linear or curvilinear equations would better describe the decline in HRmax with age in individuals of differing cardiorespiratory fitness (CRF) levels. Treadmill cardiopulmonary exercise test (CPX) results from participants (1510 men and 1134 women; 18-76 years) free of overt cardiovascular disease were retrospectively examined using cross-sectional and longitudinal study designs. Participants completing ≥2 CPX with ≥1 year between test dates were included in the longitudinal analysis (325 men and 150 women). Linear and quadratic regressions were applied to age and HRmax for the whole cohort and respective CRF groups (high, moderate, and low, relative to age and gender normative values). To test for differences among linear, quadratic, and polynomial equations, the change in R2 (cross-sectional analysis) and Bayesian information criterion (BIC) (longitudinal analysis) from the linear to the more complex models were calculated. The quadratic or polynomial regression in the cross-sectional analysis, marginally improved the variance in HRmax explained by age compared to the linear regression for the whole cohort (0.2%), moderate fit group (0.3%), and low fit group (0.8%). With no improvements in the high fit group. BIC did not improve for any CRF category in the longitudinal analysis. In conclusion, the minimal differences among linear, quadratic, and polynomial equations in the respective CRF groups, emphasizes the use of linear prediction equations to estimate HRmax.

High Cardiorespiratory Fitness Levels Slow the Decline in Peak Heart Rate with Age.

INTRODUCTION: Although it is well accepted that peak HR (HRpeak) decreases with age, there is no clear consensus on the rate of this decline and the influence of cardiorespiratory fitness (CRF) on the rate of decline. METHODS: Treadmill cardiopulmonary exercise test (CPET) results with RER ≥ 1.0 from participants (1849 men and 1469 women; 18-80 yr) of a university-based health assessment/fitness program were retrospectively examined using cross-sectional and longitudinal study designs. All subjects were free of overt cardiovascular disease and were not taking HR-altering medications. Only subjects having completed ≥ 2 cardiopulmonary exercise tests with ≥ 1 yr between test dates were included in the longitudinal analysis (418 men and 225 women). Subjects were categorized into CRF categories (high, moderate, and low) relative to age and gender normative classifications. A general linear-model univariate analysis was performed to test the effect of CRF on the decline in HRpeak with age. RESULTS: In both cross-sectional and longitudinal analyses, HRpeak declined at a significantly faster rate across the CRF categories (cross-sectional: -0.60, -0.78, and -0.87 bpm · yr(-1), respectively; longitudinal: -0.61, -0.82, and -1.02 bpm · yr(-1), respectively). CONCLUSIONS: This study provides evidence that the maintenance of a high or moderate CRF may slow the age-related decline in HRpeak in both men and women. The application of CRF-specific HRpeak prediction equations should be used to improve interpretation of HRpeak from exercise tests.

Heart rate response at the onset of exercise in an apparently healthy cohort.

BACKGROUND: The exercise test is a powerful non-invasive tool for risk stratifying patients with or suspected of having cardiovascular disease (CVD). Heart rate (HR) response during and following exercise has been extensively studied. However, the clinical utility of HR response at the onset of exercise is less understood. Furthermore, conflicting reports exist regarding whether a faster vs. slower HR acceleration represents a CVD risk marker. The primary study purpose was to describe HR acceleration early in exercise in apparently healthy individuals. METHODS: Retrospective analyses were performed in a sample (N = 947) representing a range of age and fitness (11-78 years; VO2peak 17-49 mL kg(-1) min(-1)). HR response was defined over the initial 7 min of the protocol. Associations between HR acceleration and CVD risk factors were also assessed. RESULTS: Mean increases in HR were 18 ± 9 and 23 ± 11 beats at minute one, for men and women, respectively (p < 0.05). After adjusting for gender and pre-exercise HR, only modest associations were observed between the change in HR at minute one and body mass index, resting blood pressure, cigarette smoking, physical activity, HR reserve, and cardiorespiratory fitness. CONCLUSION: There was wide variability in HR acceleration at the onset of exercise in this apparently healthy cohort. A lower increase in HR during the first minute of exercise was associated with a better CVD risk profile, including higher cardiorespiratory fitness, in apparently healthy individuals. These data suggest a greater parasympathetic influence at the onset of exercise may be protective in an asymptomatic population.