It is a common belief that the more time one spends in the gym, the bigger muscles one gets. This is true to a certain extent, but there are some other factors that come into play as well. The frequency of working out depends on many things like the individual's body type, the workout regime and his state of mind as well. You may have noticed that the best bodybuilders take a few days off every week. The reason for this is that the muscles need a chance to rest, and it is at this time of rest that the muscle groups in the body actually, start developing. A day or two of rest is absolutely imperative in the exercise routine of any individual. The answer, therefore, lies in a careful analysis of your fitness levels, your body type, and the nature and the intensity of the exercises you perform. Your fitness levels come into play, at the forefront, because simply put, the fitter you are the more you can work out. If you have been out of shape for a while your body will require more time to recuperate before, you can set out for your next session. You need to learn how to listen to your body and realize when it is asking you to stop. Putting your body through unnecessary strains and rigors will not aid you in the long run. Do not work out for more days than you feel comfortable with. Also, working out more than once a day is suitable only for professional and highly physical athletes. For a person who is a beginner, working out on alternate days is a good idea. This gives the body about 48 hours to recover and this is more than enough for this purpose. Another thing that beginners must keep in mind is that they must not overdo their workout. Lifting heavy weights from the offset is not a good idea, and this is something that needs to be built up over a period of time. There is a fine balance to be sought between the intensity of exercises and the fitness levels of a person, and once the body has found the right equilibrium it will recover faster. If you are performing cardiovascular exercises you can work out pretty much every day. Taking one day off in the week is a good idea, as these exercises are quicker and easier to recover from. These exercises are not as grueling and taxing on the body as strength training or resistance training, and human bodies can perform a lot of these exercises if they are conditioned in the right manner. It's also better to divide your cardio exercises and resistance exercises into separate days. Performing both in one day can be quite taxing for the body. For someone who is performing both these exercises on the same day, he will have to work out for around 4 days a week. You may have read recently that the famous soccer player Cristiano Ronaldo performs 3,000 stomach crunches every single day. Now your routine may not be so intense, but then again you do not have to live up to the tag of the world's most expensive footballer. But you can surely manage to do around 50-150 stomach crunches a day without much trouble. The thing about these stomach crunches is that they must be performed every day, so doing them 4-6 days a week is recommended. Working out your abs is a process that requires a lot of hard work, dedication and sincerity. But one must be careful about this form of abdominal exercise, as this can mean missing out on a few days in order to recover. Building Muscle as Fast as Possible Building muscle requires a lot of explosive strength training and resistance training. This involves the use of heavy weights and a lot of exercise equipment. It's better to focus on one body part each day, and taking a day or two off each week is highly advisable. People who are just beginning weight training should work out on alternate days, and even the most seasoned bodybuilders must take at least a day off each week. The amount of time that one does actually exercise, again depends on the strength, stamina, general fitness, gym exercise routine and workout intensity that has been adopted. At the end of the day, we see that there is really no definite answer as it all heavily depends on a lot of external factors. These factors differ for different people and each individual will have his/her own threshold of working out beyond which their body will need some amount of time in order to recover.