http://www.mayoclinic.org/diseases-conditions/high-blood-cholesterol/expert-answers/how-much-exercise-help-control-cholesterol/faq-20089331/?utm_source=newsletter&utm_medium=email&utm_campaign=heart-healthy

The surgeon general recommends engaging in at least 150 minutes of moderately intense physical activity [1] a week — about 20 minutes a day — such as cycling, dancing, bowling and gardening. More-intense activities [2] include jogging, swimming, and playing basketball, racquetball, soccer and tennis. Adding muscle-strengthening exercises [3], such as squats, arm curls and leg raises, at least two days a week increases benefit.

I think it’s useful to develop a simple criteria, hopefully to help us intuitively recognize the mild vs the intensive exercise. Here are my list of mild ones:
* pingpong
* household chore — my wife often says she gets enough exercise this way
* brisk walk — highly recommended to the elderly
* basketball in void deck
* ? standing in trains? Takes more energy than sitting, but won’t contribute to the 150min/week
* ? intercourse?