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 treadmill) while being monitored by an ECG. The intensity of exercise is periodically increased until certain changes in heart function are detected on the ECG monitor, at which point the subject is directed to stop. Typical duration of the test ranges ten to twenty minutes. Adults who are beginning a new exercise regimen are often advised to perform this test only in the presence of medical staff due to risks associated with high heart rates. For general purposes, a formula is often employed to estimate a person's maximum heart rate. However, these predictive formulas have been criticized as inaccurate because