How often should I exercise? It's a very broad and complex question. It depends on what type of training you wish to embark upon and what your overall goals are. It depends on your choice of activity and the lifestyle you wish to maintain. The FITT principle and the Overload Principle are used extensively to aid us in our quest for effective exercise. FITT stands for Frequency, Intensity, Type of Exercise and Time and the Overload Principle refers to exercising at intensities greater than normal, which in turn stimulates highly specific adaptations so the body functions more efficiently. We will look at both cardio and resistance (weight training) with these two principles in mind.
Cardiorespiratory Training
The guidelines for cardiorespiratory training (also called aerobic conditioning) are a minimum of three sessions per week and ideally five or six sessions per week. This level of training is what has been shown to produce the best results. There is little or no benefit to going over and above this level.
The heart rate level is the primary measure of intensity in aerobic or cardiorespiratory endurance training. Ideally before you start an aerobic training program a target heart rate zone should first be determined. The target heart rate zone is a function of both your fitness level and age and can be calculated as follows:
Heart rate is measured as beats per minute (bpm). Heart rate can be monitored and measured by taking your pulse at the wrist, arm or neck. An approximation of maximum heart rate (MHR) can also be calculated as follows: MHR = 220 - your age.
At the beginning of your training, a target heart rate zone of 50-70% of your maximum of heart rate is recommended. So if, for example, you are 30 years old that gives you a predicted maximum heart rate of 190 (220 - 30). Multiply 190 by 50% and 70% and your reach a target zone of 95bpm - 133bpm.
For fitter, more advanced individuals, a target heart rate zone of 70-85 percent of their maximum of heart rate may be more appropriate, therefore a 30 year old now has a heart rate zone of 133bpm – 161.5bpm.
Individuals in the beginning, when the fitness levels are just starting to improve should aim to maintain their heart rate within the target heart rate zone for a minimum of 20-30 minutes. This can increase to as much as 45-60 minutes as fitness levels improve.
Beyond the 45-60 minute mark there are diminished returns. For all that extra effort and sweat, the benefits are minimal and do not reward your exertion.
Do not give up if instant results are not seen. The current research suggests a minimum of 6 weeks is required before a noticeable improvement can be seen and as much as a year or more before a person’s peak in fitness is obtained.
In the world of running, the Ten Percent Rule should be respected and followed. Your mileage should not be increased by more than ten percent from week to week. In running, athletes are most at risk of overuse injuries and the Ten Percent Rule is designed to prevent these types of injuries occurring.
One of the most common mistakes is sticking to this principle until two weeks or the week before the race and then doubling your mileage in an effort to be ready for the big day. Unfortunately a dramatic increase like this can often result in injury and then all the effort in the weeks and months previously have been for nothing because you cannot run on the day. Resisting the temptation to do this is difficult, but when you cross the finish line and achieve your goal it will have been worth it.
Resistance Training
The frequency of resistance training is dependent upon the particular individual and what type of program you have chosen. For example, a program that works every body part every session should be completed 3-4 days a week with a day's rest in between each session.
Alternatively, a program that focuses on just one or two body parts per session, in theory you could be completed as frequently as six days per week. This level of training is common among bodybuilders and they often follow such a routine.
Remember though, each time you complete a strenuous strength training session you are taxing your body as a whole and this is why the rest periods are so important. One of the key aspects of effective weight training is to effectively achieve the appropriate overload.
Manipulation of training frequency, intensity and time of sessions must all be considered. So, no matter what exercise or goals you wish to achieve, the overload intensity, not the type of exercise governs strength improvements and therefore your success.
We all have to start somewhere and a beginner in terms of exercise is defined as anyone who has been training for less than 6-8 months consistently and correctly. When starting off exercising, frequency is very important. It is recommended to engage in 20 minutes of activity at least three times per week. This is considered to be the minimum prescribed amount. Due to the constraints of modern life, 20 minutes can be accomplished in different ways, either four 5 minute sessions, or two 10-minute or the full 20 minutes. The time can slowly be increased to gain the maximum benefits as the body adjusts. If you are pacing yourself correctly, the frequency of exercise workouts can then be increased from three to four or five per week. The common consensus for the duration of resistance training session is no longer than 45-60 minutes and remember the intensity is essential and so if this is correct a taxing or worthwhile session may only last twenty or thirty minutes.
Sometimes people think they must spend very long periods of time training, but if a higher intensity is achieved then the time can be decreased. There are a few different ways of measuring intensity with weight training. The first is by gauging it solely on how much weight is being lifted. If a 100 pounds weight is lifted ten times, this will reach a much higher intensity than a fifty pound weight lifted for five repetitions.
Another theory of measuring intensity in weight lifting is High Intensity Training (HIT). This particular training method involves complete muscle failure at the end of the sessions. This is a somewhat controversial method of training because the weight is constantly increased and so the intensity is constantly increased as well. This method may not be advisable for beginners because it can be unreliable.
It is always advisable to listen to your body; it is a very good indicator of your limitations and also levels of discomfort. Measuring the heart rate at the end of a session is a great way of obtaining information about intensity, as we saw earlier with the endurance training.
In many cases, the majority of well-designed workout programs are built around 3 to 4 weight training sessions per week. It is important not to have more than two workouts on back-to-back days. Resistance exercises that stress your muscles actually create small tears in the muscle fibers, and the muscles then need 24-48 hours to heal and repair themselves. This break in between allows for optimal recovery and when the recovery is at its best, the results will be far greater. Without enough recovery time, your body will fail to progress. Therefore, the best results will not be seen with overtraining.
Beginners can start with one set of 8 to 10 exercises that covers all the muscle groups and the same principles apply when engaging in exercises such as push ups, pull ups, etc. As you progress to a more advanced stage of your training (over 6-8 months of being correct and consistent), two training sessions per week is recommended
Maintenance
In order to maintain a certain level of fitness, continually challenging yourself is very important. Too little work may have little effect on your body, therefore causing you to waste your time. For each type of exercise, cardio or resistance, there is a maximum level of force that your body produces and your current fitness level determines the amount of force you can produce. When trying to maintain a certain level, the overload principle is still applied, as well as the FITT principle. Whether you are a beginner or expert, you should always try to work harder than your normal comfort zone. When this occurs, you will be increasing your frequency, duration, intensity and progression.
Research has shown that older people show similar adaptations of muscle fiber, capillarization and glycolytic and respiratory enzymes specific endurance or resistance-training exercise. So it doesn’t matter what age you are, you can still get plenty of benefits form exercise. This is important to remember, because even if our bodies age we can still stay fit and active.
Finally, it is important to set realistic goals for exercise. If your overall goal is to run a marathon, you must achieve several small goals, for example a 5km run, 10km run and half marathon, etc. before crossing the finish line.
Exercise is supposed to be enjoyable, so make sure that the type of activity you choose has the desired effect and is fun for you. For a great guide on how to kick off exercise this winter check out out Winter Exercise Guide 2015.