Does your workout make you physically better? Certainly! After all, isn’t this why you work out? You want stronger muscles, a better working heart and more effectively working circulatory and respiratory systems. These are the goals of all individuals involved in fitness as well as athletes.
However, contrary to popular opinion, every workout does not always produce a training effect. This means that your body will not make adaptations that will make you stronger and more fit from a cardiovascular standpoint.
Merely pumping iron for 30 or 60 minutes and running 1-2 miles does not guarantee that there will be any significant changes in the body or that you receive substantial results. This is why you must work in your target heart rate zone or do sufficiently high intensity work that truly taxes the muscles.
Getting a training effect means that the amount or level of work that you do is sufficient to cause changes in your body. These are not immediately noticeable as are changes such as muscle fatigue, increased breathing, a higher heart rate or sweating, all of which occur during a good workout.
The training effect means there are physiological and structural changes in the tissues, organs and bodily systems. These take place after the workout. Because of this it is important to know when these changes occur.
This is a difficult question to answer, especially in the areas of muscle strength, speed or power, except when it is displayed after a period of time. The only answer that is possible is that you must work long enough and hard enough to produce deep physiological changes.
In aerobic exercise the answer is easier as you need only work within your target heart rate zone for 30 or more minutes. However, it may not be a significant change as this depends on several factors but especially intensity.
When you get a training effect, your body undergoes supercompensation. This means that your body undergoes adaptational processes that improve its function. For example, your body does not merely replace all your energy stores that were used up in the workout, but deposits additional energy supplies which are needed in order to do more work in following workouts.
When you are striving to become more fit you should always start off with short, easy workouts and gradually build up. Understand it takes weeks before you become adjusted and feel comfortable with any new exercise program. Once your body has adapted to the exercises, you can then increase the intensity and gradually work up to your target heart rate or the intensity needed for greater strength.
See Biomechanics and Kinesiology of Exercise for guidelines on strength training if a beginner or novice. For athletes in specific sports, see Explosive Running, Explosive Basketball Training, Women’s Soccer: Using Science to Improve Speed, Explosive Golf or Build a Better Athlete.