Physical Activity Versus Exercise: Is there a Difference?

Quite often a client will come into the gym discouraged with their exercise program. The common complaint being lack of results. They give a list of activities they are doing but still do not see any changes in physical appearance. Yes this can be attributed to many variables but one of the key elements to consider is intensity.

We need to ask, what constitutes exercise? Is all physical activity considered exercise? The answer is no. Unfortunately there is not a general number or percentage that can be given to state that an activity is exercise. Exercise should be defined as an activity that is harder than what you may do on a daily basis. And this definition is going to vary for all individuals. It will be specific to an individual's background, possible limitations and current fitness status. What may be considered an exercise for one person may not be for another. For instance if you usually go for a walk each night after dinner, then walking (at this pace) would be considered physical activity not exercise. If you ride your bike to work everyday, cycling (at this pace) is going to become physical activity for you and not exercise.

Let's explain.

When you first try an activity, it is new to you and your body feels challenged by this unknown stimulus. As you start performing this activity on a daily basis, your body starts to adapt and overtime it will become less challenging. The truth is that you are getting better at doing that activity and you don't need to work as hard. Yes, this is an indicator of some fitness improvement but soon those improvements will plateau. In other words, when this stimulus becomes familiar, the end result will be fewer calories burned and less stress on the body. In order for the body to alter its body composition and for you to see changes in your physical appearance, the body needs to be challenged. This is called the Overload Principle. This principle states that there needs to be a stimulus of higher intensity than usually performed to elicit any adaptations or changes. Without an overload or high enough intensity, the body is not going to change. If your body can get the job done in the status it is presently in, then it's not going to make extra effort to become stronger or leaner. Your body is concerned with survival not the latest bathing suit fashion.

So what do we prescribe for someone that is "working out" but not seeing the results they want?

First thing to suggest may be to change up their routine. It could be possible that they have been doing the same thing for so long that what was once a stimulus or exercise, no longer is. Instead of using the elliptical, why not try the treadmill, stationary bike or even roller blading? Instead of doing the same exercises like the seated chest press and cable row, why not do a cable chest fly or lat pulldown?

After changing the exercises you are performing, the next step is to appropriately progress the intensity. Your body will start to adapt to this new routine and we need to keep it guessing.

For aerobic training: A suggestion would be to work at an intensity that is challenging to you. When working aerobically an intensity closest to your anaerobic threshold will elicit the most adaptations. Try not to come into the gym and beeline to the elliptical day after day doing thirty minutes at level four. Your body will soon catch on to that intensity and you will end up burning less calories and causing minimal changes to your muscles. Those calorie counters on the machines should not be your guides. They are inaccurate and are used as a marketing tool to consumers. We all know someone or ourselves that stays on a machine until they burn a specific number of calories. That calorie counter is based on a 150 lb person with no consideration for their genetic makeup or current fitness status. Someone who is more fit will actually burn fewer calories! So lets use the talk test marker. You should be exercising to a point where you are struggling but an intensity where you can still have a winded conversation.

For anaerobic training:

Have you ever seen someone in the gym on the cable row doing repetition after repetition? They have probably completed about fifty and still do not look a bit fatigued. In order to see skeletal muscle changes we need to be working within the anaerobic energy system. In other words, working at a high enough intensity where your muscles fatigue.

The first step is to stay in the anaerobic energy system. A general rule would be completing a set between sixty and ninety seconds. If you were to perform the exercise for longer than ninety seconds, the anaerobic effect would be lost and minimal adaptations would occur. Most people are concerned with the number of repetitions that they are doing. What is most important is the time that the muscle is under tension.

The next step is the fatigue factor. Not only do we need to stay within a time limit, we also need to fatigue the muscle before the set is up. There are two options for fatigue: volitional or momentary muscular failure. Volitional fatigue, a fatigue more realistic for the general client, is a subjective fatigue where they chose to terminate the set when they feel they cannot perform another repetition. Momentary muscular failure, which elicits the most adaptations, is physical fatigue where the client cannot perform another repetition even if they tried.

The key to continual success with an exercise program is strategic variation along with the proper progression of intensity and exercises. Try to recognize what is considered physical activity and exercise in your program. There is a difference and will be reflective in your end results.

References:

Gardiner, P.. Neuromuscular Aspects of Physical Activity. Human Kinetics. 2001.

Katch F.I., V. L. Katch, W. McCardle. Exercise Physiology: Energy, Nutrition and Human Performance. Lippincott, Williams and Wilkins. Fourth Edition, 1993.

Teri Mosey is an Exercise Physiologist and Instructor for Health and Fitness Certifications.

Peak Performance Fitness
http://www.peakptfit.com