One year ago, the intro to this column led to this line: "It's never been tougher." The "it" referred to being a teenager, teaching a teenager, and the real toughie parenting a teenager (though parenting a preteen can't be a walk in the park, either).

In that column, I wrote that "effective parenting today like the pursuit of health and fitness is a never-ending endeavor that's more an art than a science.Talk about a daunting job. You rarely get a break, you often get grief, and you have no manual or guidebook to follow."That's why I use the columns that appear just before the start of school each year to offer some assistance to parents by reviewing pertinent research and sharing what I've learned through teaching teens for 30-plus years and writing over 1300 health-and-fitness-related newspaper, magazine, and Internet articles.This year, the theme is simple: To take better care of your kids, take better care of yourself.Parenting is tough, but it need not make you a martyr. All your energy and focus do not have to be on your children.Countless parents have told me that their health and fitness has taken a terrible hit because the importance of it seemingly pales when compared to anything related to their kids. If you feel the same, you need a new perspective.Think of taking care of yourself as another responsibility of being a parent.Don't see making certain you get in four workouts a week as being selfish. Don't see your refusal to host a sleepover as self-centered. Taking time for yourself makes you healthy and whole and a far better role model.And what could possibly be more related to the well-being of your kids than the health and mental balance of their most influential role model?For those parents who don't feel like much of a role model because 14-year-old Bobby and 12-year-old Susie have tuned them out, listen up. Though a teen (and sometimes a sassy preteen) seemingly finds fault in everything you do (and will not hesitate to say so), your actions still exert far more influence than you may imagine.While parents who smoke probably incessantly implore a son or a daughter to never start such a life-limiting habit, there is actually something far more effective that they could do.Quit.A study of over 1000 participants published in the February 2009 issue of Pediatrics determined that the likelihood of children smoking increased with the number of smoking parents along with how often the parents smoked. The research also found the likelihood of both to be greater on preteens than teens, so the sooner a parent stops, the better.Well before that, a 1990 Addictive Behaviors study revealed this shocker: Despite the generally accepted belief that friends influence teens far more than parents, the correlation between parents smoking and teens smoking was just as strong as the correlation between peers smoking and teens smoking.To fully appreciate that stat, think of it this way: Teens who decide not to start smoking are just as likely to have parents who don't smoke as best friends who don't.Fortunately for parents who currently smoke, quitting helps your kids do the same.A 1999 Preventive Medicine study found kids who were already smoking were twice as likely to quit if a parent quit when compared to those who had a parent who smoked and continued to do so. Additionally, the research revealed that adolescents whose parents had quit smoking were almost one-third less likely to ever be smokers when compared to adolescents with a parent who still smoked.For those parents who can't get 11-year-old Eric and 7-year-old Elena to eat vegetables and limit the junk, listen up. Your children's eating habits are also affected by what you do, but the most comprehensive study performed so far finds your influence ebbs and flows depending on the strategies you use.The 2008 review of all available research published in the British Journal of Nutrition found severely controlling your children's food options does not improve your children's eating habits. Neither does offering rewards or providing them with the nutritional information needed to make proper choices.So what does? Parents who eat in a manner to be emulated. Parents who consistently chow down on healthy foods and do so without much fanfare.Additionally, the authors found that whether parents' eating habits are nearly perfect or clearly flawed, they are "enormously influential." The researchers also found that eating a relaxed, sit-down meal as a family something that in this day and age is getting harder and harder to orchestrate "provides a valuable opportunity for parents to model good eating habits."For those parents who forever prioritize and feel that becoming an exemplary eater isn't quite as pressing as becoming a nonsmoker, remember that the rate of obesity has quadrupled in adolescents in the last 30 years. Moreover, deaths resulting from obesity have increased so rapidly that they could easily exceed deaths caused from smoking by the time your children become adults.This, in fact, is expected to occur in Canada in the next year or so. Chilling, isn't it?Read about other ways that a parent's health habits influence their children's next week.