All About Strength Training
Strength training is a form of exercise whose purpose is to develop a person's muscles via some form of resistance technique, whether by use of machine, body weight, or free weights. A strength training session is designed to stimulate muscle strength by placing an increasing demand on the muscles; resistance for those muscles to work against is provided by elastic tensioning, incremental weight increases, or some other mechanical technique. The general goal of strength training is to build muscle size and strength. On a more specific scale, strength training: increases the toughness of muscle, tendons, and ligaments; improves the function of the body's joints; increases bone density; improves cardiac function; reduces chances of potential injuries; improves a body's metabolism in the short term; elevates "good" (HDL) cholesterol; and improves posture
Strength training works by placing an increasing demand (or progression of force) upon a muscle group, forcing it to work harder each instant to meet the demand. Usually, specific muscle groups are targeted. Strength training is an anaerobic activity (i.e., energy is generated directly from a body's muscle metabolism), rather than aerobic (energy is generated from oxygen intake). For example, doing continuous exercises in 'circuit training' with very little rest, draws energy mostly from aerobic energy sources. Short heavy-duty exercises, with rest breaks, are fueled by anaerobic energy sources, by the breakdown of phosphagens or glucose within the muscle. Strength training is not a sport, but rather a form of exercise which some sports, such as weightlifting or bodybuilding, incorporate as a core regimen. Many other sports also use strength training, some to more of an extent than others. For example, the track and field events of discus and shot-put require a great deal of strength training, while most team sports, including basketball, rugby, football, soccer, lacrosse and hockey, though making use of strength training, do not make it the sole focus of that sport's training.
TYPES OF STRENGTH TRAINING
Strength training comes in two types: weight and resistance. Weight training uses gravity and heavy objects; resistance training uses elasticity. Both use a counterforce to oppose the contraction of a muscle. The main difference between the two is that most of the counterforce for weight training is generated at the start of the movement to overcome inertia), while the counterforce for resistance training is at its greatest at the end of the movement. It is possible to turn a weight lift into a resistance movement by starting slowly and moving slowly throughout the lift. Resistance training can be further subdivided into isometric and isotonic training. An isotonic exercise involves moving the body against a force; an isometric exercise involves holding the body still against a force. Isotonic exercises strengthen the entire muscle throughout the entire movement; isometric exercises strengthen the muscle at and around the focus point of the force.
PRINCIPLES OF STRENGTH TRAINING
The chief principle of strength training of any type is the overloading of a muscle group. Muscle fiber then breaks down and grows back stronger. The components of strength training by which this principle is applied are: repetitions, sets, tempo , types of exercise, and generated force. One other principle of strength training is good form. All movements must be done targeting an appropriate muscle; the demand should not be shifted to another set of muscles.
Before moving forward, some of the terms that are part of strength training need defining. An exercise is a specific pattern of movement for the body that challenges muscles in a specific way. Form is a definition of the movement designed for an exercise that maximizes both safety and gains in muscle strength. Rep is short for 'repetition.' One rep is either one cycle of controlled lifting and lowering of a weight, or one movement through the form of an exercise. A set is a series of reps done one after another without any break. Rep Max or RM defines the maximum reps to be done in a set for a specific weight or resistance level. For example, if 12 reps are to be done for a weight of sixty pounds, then the RM would be 12. A RM of 1 means that only one rep should be done before taking a break; for example, an RM of 1 would likely be appropriate for a 200 pound weight. Tempo is the speed at which an exercise is to be done, on a range from quickly to slowly. A set of 1-5 reps will develop muscle size and strength, but will not develop much endurance. A set of 6-12 reps will balance development for muscle size, strength, and endurance. A set of 13-20 reps will develop endurance, with only slight improvements for muscle size and strength. Sets beyond 20 reps move into the area of aerobic exercise. An exercise session for an individual will usually be one to six sets for an exercise, for one to three different exercises. Breaks are taken between sets, and when shifting to a different exercise. The length of these breaks depends on the endurance of the individual. Generally speaking, breaks should be taken when the exercise shifts to aerobic rather than anaerobic.
Intensity, volume, and frequency are the three variables of strength training that will define an exercise program. Intensity is a measure of the amount of work that must be done to complete the activity, and is directly proportional to the weight or resistance level. Volume is a number that measures how many muscles are being worked how many times during a single exercise session. Frequency is a number that measures how many exercise sessions are completed per week. These three variables are, of course, mutually conflicting. Increasing any one of them will require a reduction in the other two. Trying to increase all three will result in overtraining, chronic soreness, illness, injury and, perhaps, acute trauma. The best mix for these three variables is high-medium-low -- make one variable high, another medium, and the third low. The exact definition of high, medium, and low will depend on the goal of the training for an individual.
BENEFITS OF STRENGTH TRAINING
The long-term benefits of strength training are:greater muscle strength; improved muscle appearance and tone; increased endurance; greater bone density; and improvement in cardiovascular fitness. Though long-term metabolic effects are still under dispute, in the short-term, strength training does improve a person's short-term basal metabolic rate for at least several hours. Muscle mass does definitely increase, with a corresponding drop in fat accumulation. Further beneficial side effects of strength training, just as with any intense exercise, are the increase in body levels of serotonin, dopamine, and norepinephrine, all of which are natural substances that counter depression and improve mood. Functionally, stronger muscles provide much better support for joints, improve posture, and reduce the risk of severe injury from everyday mishaps. Elderly people who start strength training lose less muscle tissue, and, therefore are less frail. Strength training also helps muscles weakened by an acquired disability, such as a stroke, or those muscles recovering from an injury or surgery.
Nutrition is one of the major concerns to address when starting a program of strength training. More protein is needed to build muscle. Trainers and nutritionists recommend a diet with 0.6-1.5 grams of protein per pound of body weight, which is equivalent to 1.4-3.3 grams per kilogram of body weight daily. An individual should eat a balanced, light meal one to two hours before a strength training exercise session. Drinking water throughout the exercise session is very important. A protein shake should be consumed immediately after the exercise session as a recovery drink-- in addition to a protein, such as whey, with tripedtides and dipeptides, the drink should also contain leucin as well as glucose or dextrose.Some trainers recommend additional products, such as steroids or creatine to promote muscle growth, but the effectiveness and safety of these products is still disputed.
Another major concern about strength training is the applicability of such training to children, both for safety reasons, and for the possible impact upon physical growth.Years ago, doctors recommended that children not participate in strength training because of the potential damage to the growth plates of their bones. Since then, no research evidence has confirmed this concern. Today, these concerns are largely alleviated by the proper supervision of a child, so that the child not only follows safety precautions, but also does not use improper form or excessive weight. Younger children attempting strength training, however, should be even more closely monitored, because of their lack of understanding of the consequences of unsafe actions.
To summarize, strength training, done properly with well-understood goals, will help any individual feel better, look better, and live a better life. Care must be taken, however, not to over-train, and not to lose sight of the eventual goal of a healthier body.