If you are asking if its a physical or chemical change it would be physical.
Well generally it will be a positive impact (Of course this generally depends on what the "Physical activity" is, it is generally good, reason being while exercising causes the brain to release endorphin's, as well as helping relax muscles and relieve physical tension, which can greatly help with stress.
Digestion is the breakdown of food into smaller particles or individual nutrients<span>. It is accomplished through six basic processes, with the help of several body fluids—particularly digestive juices that are made up of compounds such as saliva, mucus, </span>enzymes<span>, hydrochloric acid, bicarbonate, and </span>bile<span>.</span>
<span>There's no health advantage to changing your
weight if you are still living the same type of lifestyle that you were in
before the change occurred. If you have vices (e.g. smoking, drinking) before
losing the weight and you are still into them, then the long-term concern that
you will have is on your general health already. Vices affect how your body and
your organ systems react to the stimuli you put inside your body. If you cannot
give them up then be prepared to suffer more health consequences. <span>
<span>There's
no health advantage to changing your weight if you still have bad food choices.
Losing weight requires you to have a constant awareness about what food is good
and beneficial to you. Constantly choosing what and when to eat ensures
a continuous and healthy improvement in your body.</span></span></span>
