One of the unfortunate side effects to living a long life is that your physical capabilities degrade with the onset of age. Many elderly understandably worry about becoming victims of violent attack, realizing that criminals will target the weakest. Regular vigorous exercise can slow the aging process, resulting in a longer period of independence. In the United States, learning to use a cane to defend oneself has become moderately popular amongst senior citizens. http://online.wsj.com/article/SB121582129325447667.html?mod=hpp_us_pageone
Although canes are nothing more than a sturdy walking stick, they are amazingly versatile as a go anywhere, always ready self defense tool. This martial art was most popular during the end of the Victorian Era, when it was considered fashionable for men to carry a walking cane. A fine manual can be found here, http://www.the-exiles.org/manual/lang/lang.htm
The "Walking Stick" Method of Self Defense written by a British Indian Police officer in 1923These methods were picked up by Major W.E. Fairbairn in 1941 and widely taught to intelligence operatives of Britain's SOE and the American OSS during WWII.
Military Police veterans who received training in use of the long riot baton will find these combatives quite familiar: http://www.armystudyguide.com/content/SMCT_CTT_Tasks/Skill_Level_1/1913764121-sl1-use-a-riot.shtml
When confronted by a knife-wielding assailant, when all you have is a stick, using the stick as deadly force is defensible. The US Army MP skill level one study guide points out the five lethal strike zones where use of the a baton is NOT authorized. But defending your life against a deadly weapon and all you have is a stick, you turn this around, as Applegate Rex Applegate instructed OSS operatives in the classic treatise on combatives Kill or Be Killed http://www.americancombatives.com/aci/index/rex-applegate
If you've been to South Africa, Singapore or India and seen first hand what trained native police do with sticks (because they are not permitted to carry firearms) you will leave with great respect for this primitive weapon.