Photo by: Alila. Exocytosis is the cellular process in which intracellular vesicles in the cytoplasm fuse with the plasma membrane and release or secrete their contents into the extracellular space.
More generally, the formula for the 95% confidence interval on the mean is: Lower limit = M - (tCL)(sM) Upper limit = M + (tCL)(sM) where M is the sample mean, tCL is the t for the confidence level desired (0.95 in the above example), and sM is the estimated standard error of the mean.
Now, take 75 percent of your MHR, which will be your upper limit. Then calculate 65 percent of your MHR, which will be your lower limit. Plan to run 20 minutes total (head out for 10 minutes, then turn around). Start running until you hit your upper limit heart rate, then walk until it's back down to your lower limit. Run again up to 75 percent, then walk until you hit 65 percent. Continue this way for the entire 20 minutes.