This is Part Two of a three-part series on managing the symptoms of multiple sclerosis. The text has been excerpted from Dr. Schapiro's book, Managing the Symptoms of MS, 6th Edition, which came out this month.

Striving for increased mobility means working with whatever strengths and weaknesses you have. Muscle weakness that results from loss of strength in a muscle or group of muscles may occur for many reasons and is common to many diseases. Weakness in the muscle itself is seen in muscular dystrophy; in diabetic neuropathy the problem lies in the nerve that leads to the muscle; and in MS it is caused by a problem in the transmission of electrical impulses to the muscle from within the brain and spinal cord. This difficulty is the result of demyelination of the involved nerves, usually in the spinal cord but occasionally in the brain.

It is vital that the source of the weakness be understood to properly manage it. For example, if weakness is the result of a lazy, weak muscle, the muscle may be strengthened by lifting weights. These exercises are called progressive resistive exercises. However, when weakness is the result of poor transmission of electrical impulses, lifting weights may only fatigue the nerve and further increase muscle weakness. For people with MS, it is important to realize that exercises that involve lifting weights or repetitive movements of muscles to the point of fatigue may not increase strength but increase weakness. It is somewhat akin to a light fixture that does not work because there is a problem with the fuse. Changing the bulb or flicking the switch will not fix the problem. In MS the problem is with the fuse, and attempting to correct the problem at the muscle or nerve level will only result in frustration.

Exercises that involve lifting weights or repetitive movements of muscles to the point of fatigue do not increase strength, they increase weakness.

Efficiency is the key to increasing strength in people with MS. Energy should be conserved and used wisely. This means using your muscles for practical, enjoyable activities and planning the use of time accordingly. For example, difficult activities should be done before those that are easier to perform. The appropriate use of assistive devices also may be extremely helpful in increasing overall efficiency.

As noted, an intelligent approach to strengthening exercises is necessary. Strength also may be increased with the use of an aerobic exercise machine such as an exercycle or a rowing machine. However, the principle of not becoming fatigued and exercising those muscles that can be strengthened to compensate for the weaker muscles must be applied. In general, exercise is good, but the wrong exercises may be harmful.