I think one thing you could do in order to measure your cardiovascular strength you can do a full sprint run. In order to help improve your fitness levels you can swim, jog/run, body weight exercises, and a balanced diet.
Answer:
due to human are using resources faster than they can be renewed replace and clean up.
For substantial health benefits, adults should do at least 150 minutes (2 hours and 30 minutes) a week of moderate-intensity, or 75 minutes (1 hour and 15 minutes) a week of vigorous-intensity aerobic physical activity, or an equivalent combination of moderate- and vigorous-intensity aerobic activity.
Um...because someone put to much caffeine XD or a human does not need a lot of caffeine and coffee has more than needed
