Question:

My wife was diagnosed with MG several years ago. The only noticeable effect is in the use of her legs. She takes one to two tablets of mestinon 60mg daily and has a very difficult time without it. She has become interested in biking with me and decided she would like to take a 200 mile trip in two days. We began training and had ridden up to thirty miles with no noticable ill effects. Yesterday we joined in a sponsored rided and tried to do 70 miles. We actually rode the 70 miles but my wife was extremely tried and we had to stop frequently. She would be riding along at 12mph and suddenly drop to 6 on a flat and level stretch. She said it felt like someone had put the brakes on her body. She was having some double vision and took about 8x60mg tablets of mestinon during the 9 hours we were riding. I have tried to find more information about MG and excerise but there seems little available. Can you give us some idea about how hard she can push and is there any damage as the result of pushing hard? Does the strenous exercise build muscle and endurance in a MG individual? Can you give us any place to obtain further information? When she has talked to her physician he seems to think she is silly for wanting to live a full life and be that active physically. We are 60, but there are a lot of 60 year old people out there. Can it cause damage or increase the speed of the disease process if she exercises strenously? Will further training improve her ability to ride further or faster?

Answer:

“Too much exercise” differs from patient to patient. Exercise which brings on specific MG symptoms (double vision, chewing or breathing trouble,…) is undesirable. Becoming sedentary and deconditioned is also undesirable. The key to managing MG is to balance benefits against side-effects. If your wife is able to most things with a regimen which is safe, that may be the best plan. To demand that she be able to perform physically well above the average person may require stronger (and most often riskier) treatment combinations. Stenuous exercise will condition and strengthen a patient up to the point that it causes MG symptoms. I would recommend a less strenuous program that leads to good (but not necessarily fanatastic) cardiovascular conditioning. On the next cycling trip, have you wife drive the second half of the distance (just stash your car at the half- or quarter-way point). Portions of this answer were researched and reviewed by Dolly Boughaba, MD, NetWellness.org Neuromuscular Section.

For more information:

Go to the Myasthenia Gravis health topic.