Lucille has been told she needs to improve her heart health, and she's ready to get started. there are many activities she is considering for her new routine, but she knows she must first calculate her target heart rate zone. when is the best time for her to begin gathering data to do this calculation?

The best time would be right away because once she has got that information she can start planning her changes in her lifestyle to improve her heart health. First of all she should get a good nights sleep that always helps your heart health and also regularly she should get her bp checked because it is always good to know how your heart and you are feeling. Hope this helped  

Muscles in the body us with a lot of things for example, if i wanted to lift a heavy box and had no muscle i would just collapse where i was because of the fact muscles hold us together. overall they are 650 muscle in the human body, all of them have different purposes and ways to keep us together. there are three types of muscle in the body skeletal, smooth, and cardiac muscle. skeletal muscle are attached to the bone and with movement. smooth muscle, this is found in the wall of our organs, such as our stomach, this muscle with movement   as well, without this muscle, we would only be allowed to eat small amounts. the cardiac muscle is the heart muscle and probably the most important one. these are only found in the walls of the heart and the heart pump blood to the other parts of your body. we have two different types of muscle fibers, slow twitch and fast twitch. slow twitch muscles enable long-endurance feats such as distance running. fast twitch fatigue faster but are used in powerful bursts of movements like sprinting. there are three different types of muscle contractions concentric, eccentric, isometric. concentric contraction causes muscles to shorten, thereby generating force.   eccentric contractions cause muscles to elongate in response to a greater opposing force. isometric contractions generate force without changing the length of the muscle.: //athleticquickness.com/muscle-contraction-types-part-1/

Stimulants speed up the central nervous system.