Basal metabolic rate be elevated in stress, illness, and diabetes. Menopause may also affect metabolism. Heart rate is determined by the medulla oblongata and part of the pons, two organs located inferior to the hypothalamus on the brain stem. Heart rate is important for basal metabolic rate and resting metabolic rate because it drives the blood supply, stimulating the Krebs cycle. During exercise that achieves the anaerobic threshold, it is possible to deliver substrates that are desired for optimal energy utilization. The anaerobic threshold is defined as the energy utilization level of heart rate exertion that occurs without oxygen during a standardized test
Heart rate they generalized population-averages and usually focus on a person's age. It is well-established that there is a "poor relationship between maximal heart rate and age" and large standard deviations relative to predicted heart rates. ("see Limitations of Estimation Formulas"). A number of formulas are used to estimate HR Based on measurements of 3320 healthy men and women aged between 19 and 89, and including the potential modifying effect of gender, body composition, and physical activity, Nes "et al" found This relationship was found to hold substantially regardless of gender, physical activity status, maximal oxygen uptake, smoking, or body mass index.