Tips. 1  If you want to focus on a particular muscle area, you can do so by changing the stride length. 2  For an elliptical with multiple users, use one whose stride length is adjustable to accommodate different heights. 3  Do not rely solely on guidelines.
3. Intercellular chemical signals secreted into the circulatory system; carried to organs they control, where they bind to receptors and produce a response. 4. Intercellular chemical signals, secreted by nerve cells; important in the function of the nervous system.
The endocrine system broadcasts its hormonal messages to essentially all cells by secretion into blood and extracellular fluid. Endocrine system is chemical and slow in nature. The nervous system exerts point-to-point over body control through nerves. Nervous system control is electrical in nature and fast.