<span>Physical fitness is something that constantly needs to be worked on to maintain or improve it. Thus, it has a continuous nature. Think of running a mile. If you train for weeks, you can achieve a faster time. Once you attain the goal mile time that you want, you still have to keep training to further maintain it. However, if you stop running, the time it takes to run a mile will increase, and your physical fitness will decrease. This shows the concept of physical fitness as continuous, because to maintain or improve it, you must continue training.</span>
I would say dancing,because its one of the exercise that you can do.
hope this helps..
Vaccinations were first used in the year 1796.