It takes 6 weeks for anything new to become a habit. If you are new to exercise it will take your body about 4-6 weeks of regular training to notice a change before it starts making positive adaptations. It will take a while for your metabolism to increase so you burn more calories (even during rest) and for your muscles to get a bit more flexible, toned, stronger and fitter.
If you have done lots of running in the past for example (which is one type of training - cardiovascular / aerobic) it will take you about 4-6 weeks of regular attendance to get used to circuit training (which is three types of training combined - cardiovascular / aerobic - muscular / skeletal / core training - anaerobic / interval training).
Set yourself short term achievable goals:
For women you can't expect to eat healthy and train hard for 1-2 weeks and turn yourself into a supermodel that fast, likewise for men you can't suddenly lift a few weights and do a few pressups for 1-2 weeks and expect to look like Arnold Schwarzenegger!
Look at healthy eating, a healthy lifestyle and a regular exercise routine as a long term career and not a short term fad and you'll soon look and feel better for it!
