Strength training exercise programs involve exercises that cause the muscles to contract against external resistance either by means of weight training, high-resistance machines, rubber tubing or your own body weight with exercise that is limited to a few repetitions (generally less than 20) before exhaustion.
Weight training, resistance training and isometric training are all types of strength training.
Strength training is recommended by national health organizations for incorporation into a comprehensive fitness program that includes aerobic and flexibility exercise. The potential benefits of strength training on health and performance are numerous.
Strength training has been shown to reduce body fat, increase basal metabolic rate, decrease blood pressure and the cardiovascular demands to exercise, improve blood lipid profiles, glucose tolerance, and insulin sensitivity, increase muscle and connective tissue cross-sectional area, improve functional capacity, and relieve low back pain.
Many improvements in physical function and athletic performance are associated with the increases in muscle strength, power, endurance, and hypertrophy observed during strength training.
Strength training helps offset the loss in muscle mass and strength typically associated with normal aging. Additional benefits from regular exercise include improved bone health and, thus, reduction in risk for osteoporosis; improved postural stability, thereby reducing the risk of falling and associated injuries and fractures; and increased flexibility and range of motion. Participation in regular physical activity (both aerobic and strength exercises) elicits a number of favorable responses that contribute to healthy aging.
Health Benefits of Strength Training
*Better Muscle Strength
Adults who engage in strength training are less likely to experience loss of muscle mass, functional decline, and fall-related injuries than adults who do not strength train. Studies on strength-training interventions have indicated that inactive older adults who begin regular strength training achieve substantial strength gains within a few months.
Strength training improves the interplay of the muscles (inter-muscular coordination), and in addition, with more advanced training intensity; the muscles learn to make greater use of the muscle fibers (intra-muscular coordination). A firming up of the tissue becomes visible and, above all, the muscle mass increases.
A randomized controlled trial of 164 overweight and obese women (25-44 yrs) was conducted to determine the efficacy of twice-weekly strength training to avoid increases in percentage body fat and intra-abdominal fat (hidden abdominal fat surrounding the organs).
The results of the study indicated that strength training is an effective intervention for preventing percentage body fat increases and reducing intra-abdominal fat increases in overweight and obese pre-menopausal women.
Calorie consumption increases dramatically with every extra pound of muscle mass, even while sleeping.
* Protection Against Injury
The resistance exercise-induced changes in aged skeletal muscle in the elderly are associated with numerous health benefits, the most obvious of which are the gains in strength, and functional independence is improved and the risk for falls is reduced.
Resistance training has been shown to reduce fall risk in the elderly (75 to 85 yrs) by significant reductions in sway that are associated with improved strength.
Osteoporosis, or inadequate formation or decrease of bone mass, is becoming increasingly common, not just in women but even in men. The latest research results show that amount of movement is decisive in how well bone matter is built up and maintained. The first three decades of life are the most important, the greater the peak bone mass during this period, the greater will be the protection for the subsequent phases of life. Strength training does not just help preventatively, however, it also has a rehabilitational effect, in that it can slow down and reduce the reduction in bone density. In addition, strong muscles protect the joints from trauma.
Concentric and eccentric isokinetic resistance training increases bone mineral measurements in young women.
It has been suggested that resistance training can improve bone mineral density (BMD) in postmenopausal women, and also constitute potential therapy to improve functional ability and the quality of life in osteoporosis patients.
Resistance exercise has been shown to be effective in improving integrated glucose concentration, including reducing peak glucose concentrations in women with type 2 diabetes.
Known benefits of resistance training in type 2 diabetic patients are improved insulin action, insulin sensitivity, fasting blood glucose and insulin, and glucose tolerance levels. Actions of pro-inflammatory mediators linked to dysregulated innate immune activity have been associated with type 2 diabetes. The immuno modulatory effects of resistance training may provide a strategy to counter these pro-inflammatory effectors.
The results of a small study suggest that progressive resistance strength training is a feasible fitness option for some people with multiple sclerosis.
Muscle strength increased significantly in a study of post-stroke patients after progressive resistance training and is an effective intervention to improve muscle strength in chronic stroke.
*Kidney Disease Patients
Resistance training increases muscle strength physical functionality, and improves insulin-like growth factor-1 (IGF-1) status in chronic kidney disease patients who are undergoing hemodialysis treatment.
*Breast Cancer Survivors
Weight training for recent breast cancer survivors may result in improved quality of life, increased muscle mass, as well as decreased body fat % and, insulin-like growth factor-II (IGF-II).
High intensity progressive resistance training (PRT) is effective for the treatment of older depressed patients.
* Cerebral Palsy
A strength-training program was conducted in homes of eleven young people with spastic diplegic cerebral palsy (CP). Gross Motor Function Classification System scores ranged from I (walks without limitations) to III (walks with assistive device).
Benefits included perceptions that strength, flexibility, posture, walking, and the ability to negotiate steps had improved. In addition, participants reported psychological benefits such as a feeling of increased well-being and improved participation in school and leisure activities.
* Posture Improvement
Well-developed muscles will correct bad posture and enhance your figure.
In older men, low circulating testosterone is associated with low muscle strength, and studies of testosterone replacement have reported resistance exercise training to be effective in elevating testosterone levels.
Muscle mass begins to decrease at the age of 30 largely due to an inadequate amount of exercise. A strength training exercise program can minimize age related declines such as cardio respiratory fitness, strength, power, and, indirectly, balance.
Resistance training has been shown to reduce back pain women with low bone mass.