You must build muscle to stay young and healthy, lifelong.
Although there is an emphasis on skeletal muscle, don't forget there is also smooth muscle in your organs and your heart is made of cardiac muscle. Here is a summary of the latest research on the benefits of weight training.
According to Dr Michael Colgan, between the ages of 20 and 40 the average female loses 3.6kg of muscle and gains 10 kg of fat. Between 20 and 80 the average male loses one quarter of his muscle mass. Running, cycling or other aerobic sports will not prevent this loss. In a representative study of the evidence, researchers at McMaster University , USA , compared a ten week programme of weight training plus aerobic exercise against aerobic exercise alone. The aerobic group showed only a 2% increase in cardiovascular capacity and an 11% increase in endurance. The weight training plus aerobics group showed a 15% increase in cardiovascular capacity and a massive 109% increase in endurance. For strength the results favoured weight training even more. The aerobics group showed no increase in arm or leg strength. The weight training group showed a 43% increase in arm strength and a 22% increase in leg strength.
NOTE: To be sure you are fully benefiting from your exercise routine and losing fat rather than muscle, monitor your active tissue mass with a Bioelectrical Impedance Analysis or BIA.
Remember, muscles are controlled by nerves. The electrical stimulation of nerves and contraction of muscles are the result of the exchange of electrolyte minerals dissolved in water. It's essential that you drink water for health and building muscle. Without enough water, your muscles are not getting enough electrolytes. Muscle strength and control are weakened. If you want to build muscle, then you must keep your body hydrated.
Muscle is the engine in which body fat is burned for fuel so if you don't have much muscle you can't lose much fat. A representative study published in the American Journal of Clinical Nutrition compared the levels of body fat in groups of women, showing sedentary women have 21% body fat, aerobic exercisers have 16% body fat, and resistance exercisers have 14% body fat.
The bone benefits of weight training are well illustrated by a study of bone density in weightlifters from 14 different countries, compared with healthy subjects who didn't lift weights. On average the weightlifters bones were 46% more dense and an estimated 50% stronger. Bone strength and muscle strength are highly correlated not only in weightlifters but also in healthy young women. A study at Stanford University showed clearly that about 20% of bone mineral density is dependent on maintaining muscle. A new study reported in February 2000 in the British Journal of Sports Medicine shows that even in elderly women, a one year weight training program increased their strength by 19-29% with a concomitant increase in bone density.
Immune strength depends on availability of the amino acid glutamine, and your muscles have to supply the glutamine to your immune system in order for it to work. The more muscle you have the more abundant the glutamine supply, and, other things equal, the better your immune system works.
New studies published between 1995 and 1999 show that weight training has an unexpected benefit - it improves glucose tolerance in patients with Type 2 (adult onset) diabetes, In one of these studies, postmenopausal women with diabetes followed a weight training programme for four months. Their glucose sensitivity to a challenge improved by an average of 20%.
At Tufts University , researchers gave patients with rheumatoid arthritis 12 weeks of high intensity weight training. Results showed significant reductions in joint pain and fatigue and a big gain in strength. Another study at the University of Nebraska gave a group of patients with osteoarthritis of the knee an 8 week strength training program. Another patient group with the same arthritis was used as a control. Results showed that the weight work caused a significant decline in arthritis activity.
Research shows that weight training causes fewer heart symptoms than traditional rehabilitation exercises like fast walking, jogging or cycling. It also yields better coronary artery flow, greater muscle strength, greater submaximal endurance and less fatigue. In one new study, a 12 week weight program was added to a conventional heart rehabilitation aerobic exercise program.
The group doing weights plus aerobics showed much greater increases in strength (90% as opposed to 9% on aerobics alone). They also lost more body fat (2.8kg as opposed to 1.3kg); and improvements in endurance.
Muscle produces 60% of your glutamine. Glutamine is a precursor to the antioxidant glutathione, the brain's master antioxidant. Glutamine is considered to be a non-essential amino acid because it is made by the body and technically not required to be obtained through the diet. Although we do get some glutamine in our diets, it is necessary for the body to produce more to meet the vast amounts required.
The major tissue in the body for producing glutamine is muscle. Muscle is capable of combining ammonia and the amino acid glutamate to form glutamine. The production of glutamine in the muscle is so great that it accounts for more than 60% of the free amino acid pool in muscle cells. These large muscle stores also account for most of the body's glutamine reserves, and they can release glutamine into the circulation to maintain plasma levels and provide other tissues with glutamine.
Free radicals and oxy radicals play an important role in the development and progression of many brain disorders such as brain injury, neurodegenerative disease, schizophrenia and Down syndrome.
Glutathione, whether you are young, middle-aged or old, low blood levels of the antioxidant glutathione predict disease and premature death; levels decline dramatically around age 40. Glutathione is the body's main detoxifier of toxins, which is critical to survival. It also turns off inflammation and restores declining immune functions according to Lester Packer, Ph.D., a molecular and cell biologist at the University of California at Berkeley.
The best way to increase glutathione is to take lipoic acid, says Packer. In cell cultures, he has found that lipoic acid boosts glutathione levels by a remarkable 30 percent. Unfortunately, a glutathione supplement does not boost levels in the body; it is destroyed by digestive enzymes before it gets into the blood.
Glutamine is best known for its ability to serve as a source of fuel for the cells that line the gastrointestinal tract. More specifically, glutamine is the preferred fuel source for cells lining the small intestine. By nourishing these cells, glutamine helps maintain the health and integrity of the gastrointestinal tract. A healthy gastrointestinal tract is vital to preserving overall well-being, as the lining of the gastrointestinal tract serves as a first line of defense against disease-causing microorganisms and also minimizes the absorption of potentially allergenic molecules. Glutamine also serves as a source of fuel for muscle and immune cells.
In addition, glutamine plays a role in maintaining the body's proper acid-base balance. Glutamine is synthesized from glutamate and ammonia. Ammonia is a toxic waste compound with a high pH value, meaning that it is basic (as opposed to acidic). When ammonia levels are elevated, the body clears ammonia from the blood by synthesizing glutamine. If the blood is too acidic (pH too low), the body can break down glutamine into glutamate and ammonia to increase the pH of the blood. See Health Secret 5 about maintaining an alkaline diet.
So the health benefits of lean muscle mass is obvious. The need to build muscle is 1 of 6 health secrets; consider them all.
Overweight is not necessarily over-fat.
To be sure you are fully benefiting from your exercise routine and losing fat rather than muscle, monitor your active tissue mass with a Bioelectrical Impedance Analysis or BIA.