Some simple rules for Health, Fitness and Happiness.
Feeling healthy, fit and happy takes a bit of effort. My clients hear me go on about getting their nutrition right 80% of the time so that if it does go wrong occasionally its not the end of the world!
I like to promote exercise for a minimum of 20 minutes 4 or 5 times a week. You need to keep this regime going for a few weeks; the body has to realise it needs to improve (become stronger and more economical) Remember that when we say exercise 4 or 5 times a week it can be anything from a HIIT workout to swimming with your kids or even a 45 minute walk!
Tony Horton breaks it down nicely here with a few rules to live by (he is a bit full on but the message is great, please watch it).