Until the muscles, tendons and joints are "ready," the pounding of running may make your introduction to the sport an undesirable experience.
Besides doing the proper advance work, other factors influence whether and how much individuals should run.
Often, people who are very overweight ask me how to get started. They have heard running is a great way to lose weight.
Recently a 12-year-old girl asked me, "Do you think I could be ready for a half-marathon in two months?"
She had been running no more than 3 miles at a time. Her real goal, she confided, was to run a marathon (26.2 miles) as soon as possible.
A gentleman who was 69 years old called me because he was experiencing tightness in his calves every time he walked. Just before he hung up the phone, he asked, "Do you think I should start running instead of walking?"
The answer to these training questions depends on the physiological readiness of each individual. Maturity, age, exercise experience, physique and weight, and present fitness level will help determine what one can or can't do. Common sense also provides insight as to the best way to address the three scenarios.
No one should try to step up from running 3 miles at a time to running 13.1 miles with only two months to train, especially a prepubescent athlete who is still developing and growing. The kind of stress that training for a half-marathon would place on young joints and connective tissues might be harmful and, in my opinion, would be completely unnecessary.
For this reason, the minimum age for most marathons is 17. I have helped three 17-year-olds successfully go the full marathon distance. They each had accumulated a great base of cross-country mileage prior to attempting a marathon. They had their parents' blessings, and they were ready.
At age 69, someone who is regularly walking and maintaining aerobic fitness should be commended and encouraged to remain active. If you are doing well walking, there is no need to run. Running is much more stressful than walking. It may tighten up the calves even more.
I am a runner and a walker. Every other day I run, and I also enjoy walking a couple of days a week. At age 48, my "off-running days" provide me with the rest and recovery my body requires.
As we age, I believe the primary goal should be to stay in motion so we can maintain a high level of fitness. Maintaining an active lifestyle through walking is probably the smart move for most senior citizens.
If a 69-year-old man starts running and gets injured, his fitness level might really suffer. Older muscles and joints usually aren't ready for the pounding that running exacts on the body.
The principle of readiness applies to all age groups among those who have not exercised on a regular basis for several months. It especially applies to anyone older than 35 who has not exercised for several years.
It is important to acquire a base of muscle fitness and aerobic fitness before challenging yourself with overly ambitious training goals.
Mark Higginbotham is a certified running coach and personal trainer and the founder of Memphis In Motion (www.memphisinmotion.com). He teaches monthly classes on fitness and nutrition and leads adult walking and running programs locally.