Fit by foot

What is the best form of exercise for your knees?

KINESIS PERSONAL (photo credit: Courtesy)
(photo credit: Courtesy)
I’ve been told that walking is a good way to defer loss of cartilage in the knees. Is the effect of a brisk walk on the treadmill or another device equivalent to a brisk walk around the neighborhood? Please compare the health benefits of exercise on an elliptical machine and those of walking or running on a treadmill. I understand that the elliptical machine exercises the legs and arms and the heart and thus produces both aerobic and non-aerobic exercise. Are there any differences in exercise benefits between manual (magnetic) machines and electric machines?
– P.C., Binyamina
Family physician Dr. Naama Constantini, who is a leading sports medicine specialist at Hadassah Optimal and the Hadassah University Medical Center’s orthopedics department, as well as chairman of the Israel Olympics Committee Medical Commission, replies:
Walking is excellent for your health and can be done indoors on a machine or outdoors.
The benefit of walking indoors is that it can be accomplished at any time of day, without traffic, sunburn or air pollution, and in any weather. Vigorous walking does not erode bone cartilage – unless you walk on uneven ground, such as over stones. Running with impact on the legs can be risky if you have knee problems, but if you don’t, there is no orthopedic reason not to do it.
In general, people should do the type of exercise they enjoy.
Elliptical machines, which involve a rowing motion while at the same time walking or running in an elliptical motion, can be very beneficial, and it does not burden the knees or erode their cartilage. The elliptical machine uses arms as well as the legs, activating more muscle groups and the heart and lungs, while using up somewhat more energy.
But if you are interested in preventing or relieving osteoporosis, the elliptical device will not help, as the foot is always supported and does not land on the ground. This means there is not much gravitational impact on your femur and tibia bones to trigger the growth of bone cells. In this case, you should walk briskly or run outdoors or on a treadmill, or learn other bone-impact exercises.
There are differences among exercise machines. Using a manual/magnetic machine may mean that you use more muscle than on an electrical machine, but there aren’t significant differences in benefits. When you go to buy an exercise device or use one at a gym, try it out to make sure you are comfortable with the angles and toughness or softness of the motion.
Regarding the Jerusalem Post article published in December about new government restrictions on cigarette vending machines (“Cigarette vending machines outlawed within one kilometer of schools,” December 22), I was wondering whether the Health Ministry has already ordered that cigarette machines within a kilometer of educational institutions be removed. How many complaints has it received around the country? It would seem to be a simple matter to send an inspector to investigate complaints, follow it up with a letter and demand that the vending machine be removed immediately.

In early January, I called the Health Ministry at its information number *5400 to report a cigarette vending machine in Jerusalem’s Baka neighborhood that is clearly close to several schools. Over a month later, it was still there and operational, and many minors surely buy cigarettes from it, even though it is illegal to sell tobacco products to them. Why doesn’t the ministry take action? I was also upset that the government gave cigarette vendors until January 1, 2014, to eliminate all vending machines when the owners claimed they had to cover the cost of their investment in them. Surely the vending machines can be retrofitted so they can sell products that are not dangerous to health.

– E.M., Jerusalem
Haim Geva Haspil, the health promoter and coordinator in the field of smoking prevention in the Health Ministry’s department for health promotion, answers:
Soon after Deputy Health Minister Ya’acov Litzman’s regulation took effect almost two months ago barring cigarette vending machines within a kilometer of schools, the ministry – via the media – asked the general public to report on violations. Through directives, it also asked school principals and teachers and the local authorities to report cigarette vending machines that violated the regulation.
So far, it has received some 30 complaints, mostly via our “Kol Habriut” *5400 number.
They were dealt with systematically. In general, handling complaints against vendors is the responsibility of the local authority, whether the machine is on the sidewalk or in a store.
The local authority can cancel the business license. There are vending machines that have already been removed, while there are others in various stages of the elimination process. When a bill being promoted by the ministry to empower inspectors to enforce various laws against smoking is enacted, it will make it much easier than before for us to take action.
As for allowing the owners to remove all cigarette vending machines in two years, ministry director-general Prof. Ronni Gamzu successfully fought to get that cutoff date instead of the original one giving them another year [beyond 2014] to “adjust.”
Rx for Readers welcomes queries from readers about medical problems. Experts will answer those we find most interesting. Write Rx for Readers, The Jerusalem Post, POB 81, Jerusalem 91000, fax your question to Judy Siegel-Itzkovich at (02) 538-9527, or email it to [email protected], giving your initials, age and place of residence.