Obesity-associated metabolic changes influence resting and peak heart rate in women and men.

OBJECTIVES: To study the relationship between obesity and heart rate (HR) in women and men. DESIGN: We studied 241 overweight and obese subjects without known heart disease. All subjects underwent ergospirometry during maximal exercise testing on treadmill and recording of body composition, electrocardiogram and clinic and ambulatory blood pressure. RESULTS: Women (n = 132) were slightly older and had higher fat mass, but lower weight, blood pressure and prevalence of metabolic syndrome (MetS) than men (n = 109) (all p < 0.05), while prevalences of obesity and hypertension did not differ. A significant interaction between sex and HR was demonstrated (p < 0.05). In multivariate analysis, female sex (ß = 0.99, p < 0.01) predicted higher resting HR independent of confounders. Higher resting HR was particularly associated with presence of MetS, hypertension, higher insulin resistance and lower relative muscle mass in men (all p < 0.05). Female sex also predicted higher peak exercise HR (ß = 0.48, p < 0.01) independent of confounders. Higher peak exercise HR was particularly associated with higher exercise capacity and lower age and self-reported physical activity in men, while lower HbA1c and absence of obesity were the main covariates in women in multivariate analyses (all p < 0.05). CONCLUSIONS: In our study population, obesity and obesity-associated metabolic changes influenced both resting and peak exercise HR.

Determinants of systolic blood pressure response during exercise in overweight subjects.

AIM: Higher systolic exercise blood pressure (BP) is associated with increased cardiovascular risk in hypertension. We aimed at identifying covariates of systolic exercise BP in overweight subjects. METHODS: 77 subjects with body mass index (BMI) > 27 kg/m(2) and without known heart disease were tested. BP was measured by sphygmomanometry before and at all exercise stages during maximal exercise capacity testing on a treadmill. High peak systolic exercise BP was defined as ≥ 200 mmHg. RESULTS: The study population was 48 ± 10 years and included 60% women and 42% with known hypertension. Average BMI was 32.6 ± 4.8 kg/m(2) and clinic BP 132/82 ± 17/8 mmHg. High systolic exercise BP was found in 32%. Subjects with high systolic exercise BP had higher systolic clinic and 24-h ambulatory BP (ABP), as well as lower peak oxygen uptake, compared with subjects with normal systolic exercise BP (all p < 0.05). In multiple regression analysis known hypertension (ß = 0.33), higher systolic ABP (ß = 0.22) and high-density lipoprotein (HDL)-cholesterol level (ß = 0.23, all p < 0.05) predicted higher systolic exercise BP independent of sex and peak oxygen uptake (multiple R(2) = 0.32, p < 0.001). CONCLUSION: Among overweight subjects, known hypertension, higher systolic ABP and HDL-cholesterol level were the most important factors predicting higher systolic exercise BP.