Your decision to start exercising is a good lifestyle choice.  Many people start working out and quickly give up because they do not see the results that the wanted. Or they discover the exercise they have chosen is not for them so they decide to quit instead. 

These reasons and so  many more are given for not continuingto work out are given. Exercise and working out  is a life long commitment. People oftentimes will start a program to lose  weight and stop working out after they have reached their goal. 

Only to end up where they started several months down the road. This  is why it is critical to realize when starting an your exercise program or a new diet, it should be a lifestyle change, something you want to do for yourself for the rest of your life.

http://hubpages.com/hub/Fitness-Tips-For-Beginners-Starting-An-Exercise-Program