Strength Training: The Science Behind Building The Perfect High-Performance Body
The science of strength training begins with understanding the term, “One Repetition Maximum’. One Repetition Maximum – refers to the maximum load or resistance that an athlete can lift once, but cannot lift a second time, without a recovery period. Thus, a 5 repetition maximum refers to the maximum load an athlete can lift 5 times, but not six within a given set, and so on.
As a rule, in order to increase muscle hypertrophy when performing weight training the resistance selected is usually between 70-80% of the athlete’s one repetition maximum for that particular exercise (moderate resistance), or between 85-90% of their one repetition maximum (high resistance). As an example, it the subject’s one repetition maximum for the bench press is 200 lbs, then they may choose to lift 150 lbs (75%) or 170 lbs (85%), enabling them to perform 6-9 repetitions per set, as a means to gain strength and muscle hypertrophy. As the athlete becomes stronger and their one repetition maximum increases, then they need to increase the resistance in accordance with their increased strength, in order for additional strength gains to occur. This is known as the overload principle of training.
Rest intervals between sets should be approximately one minute when training at 70-80% of one repetition maximum (these are athletes who need to work under conditions of higher lactic acid build up, such as hockey and basketball players), whereas rest intervals between sets, when training at 85-90% of one repetition maximum, should be 2-3 minutes to restore sufficient phosphagen stores for the next set.
Circuit Training – circuit training allows an individual to acquire a modest cardiovascular benefit, while performing a weight training routine. The individual performs 12-15 repetitions of a weight training exercise (40-60% of one repetition maximum), and after only a 30 second rest interval moves to another exercise station and does another set of 12-15 repetitions and so on. The high repetition work, coupled with the very short recovery period between sets, keeps the subject’s heart rate elevated, and has been shown to increase VO2 max. by 5-8%, which is a superior oxygen utilization gain compared to standard methods of weight training. However, the overall strength gain from circuit training is far less than other methods of weight training and the oxygen consumption improvement (5-8%) is far less than occurs with traditional methods of aerobic training. Circuit training has its best application for patients with heart disease, who wish to add a component of strength training to their work out routine (note that the maximum heart rate for these patients must first be established by their attending physician), and for patients who wish to lose weight, but also want a muscle toning effect, and only have 30-40 minutes to exercise, three times per week.
Increased Metabolic Rate And Fat Burning – as you increase your muscle mass through strength training and ingesting the right amount of protein each day, you will also increase your resting metabolic rate. Every pound of additional muscle you gain will demand that your body burn an extra 35-50 calories per day, just to keep it alive. Thus, if you gain 10 pounds of muscle, which you can easily do in less than a year, you will raise the number of calories your body burns at rest each day by up to 500 calories. Each week you will burn an extra 3500 calories. That is significant because each pound of fat on your body represents 3500 calories. So, you will be burning an extra pound of fat each week in your resting metabolic rate, just by adding 10 pounds of lean mass over the 600 muscles of your entire body. This means, by the way, that you will lose four pounds of fat each month as you burn it up in your resting metabolic rate, while you are sleeping and sitting in a chair. This is how strength training pays big dividends in reducing body fat and helping to keep body fat off, while enabling you to eat more of the right calories. A person’s basal metabolic rate (BMR) accounts for 60-80% of the daily calorie or energy expenditure. Overall, your BMR is affected by:
- your body surface area –ectomorphs burn more calories to maintain sufficient body heat internally because they lose more heat to the environment to a larger total body surface area (basketball player build is an example of an ectomorph)
- fat-free mass (lean muscle mass)
- thermic effect of food
- genetic background
- aging (1-2% decline in BMR per decade from ages 20-75, unless the person maintains their fat-free mass with resistance training and the appropriate protein intake)
For both males and females, at any age, the best indicator of their BMR is their total fat- free mass, or lean mass (assuming no underlying thyroid condition). This is an important reason to maintain your muscle mass through strength training throughout your entire life.
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3. Physician and Sports Medicine: Principles of Resistance Training, 1988; March, April, May, June editions.4: 231-237