10 years ago, I made a simple change that improved my life dramatically

I don't believe in New Year's resolutions.

But 10 years ago today, I changed something. And that change turned out to be one of the best things I've ever done.

I started exercising regularly.

At the time, I didn't think of myself as particularly lazy or out of shape. I was never a jock, but I was a competitive swimmer until my junior year of high school. I skied in the winter and played a lot of pickup games in the neighborhood where I grew up, mostly street football and basketball.

As I got older, most of that went away, and I started spending a lot more time sitting at a desk. But I still did a lot of hiking, learned to scuba dive, and bought a bike, and used it from time to time ... that kind of thing. I thought I was in OK shape.

But on New Year's Day, 2006, I woke up feeling fat and bloated and gross.

So my wife suggested I go join a gym.

Resistance

A gym? I was never a gym person. I didn't like the whole culture, the weird nutritional additives, the crash diets, the mirrors everywhere. And what were all those machines? I didn't know how to use them and thought I'd hurt myself or look like an idiot.

But it was New Year's Day - a day for changes - so I sucked up my pride and went down to one of the big chain gyms in downtown Seattle and signed up. I even got a few sessions with a personal trainer.

At first, it sucked. I was in horrible shape! I couldn't lift any weight at all. My chest burned after five minutes on the cross-trainer. I sweated a ton, which was uncomfortable. I didn't have the right clothes. My feet hurt. I hated the way I looked in the mirror. It was really hard waking up in the morning and driving downtown when it was still dark outside.

But I kept at it. Day after day after day. It took a full six months before I felt comfortable and over a year before it became a truly consistent habit.

I've now gone to the gym at least three times a week, for at least 45 minutes, almost every single week for the past 10 years. The only exceptions have been when I was sick, hurt, or moving.

Here are some things that have changed:

• I can sprint for a bus or train without my chest burning like a furnace. I'm back to normal breathing in seconds, not minutes.
• I can walk up multiple flights of stairs or a steep hill without having to stop and rest.
• The random back and neck and sciatic nerve pains that I used to get every couple of weeks have almost completely disappeared. (Though I've occasionally strained or pulled muscles through stupid use of machines. Stretch! If something feels wrong, stop!)
• I used to have horrible insomnia. Now I fall asleep easily (except on the first night in a hotel, for some reason), and if I wake up early, I just go work out.
• I'm a lot less embarrassed to go swimming, or look at myself in pictures.
• My digestion is better - no heartburn, no stomach pain, no other stuff.
• I almost never get sick. Maybe once a year. I used to get colds at least three or four times every winter.

More subtly, my outlook has changed. When things go wrong - as they inevitably do - I look to fix them rather than fretting about them. I whine less. I talk less, and listen more. I look more to the future and less to the past.

Some of this might just be a byproduct of growing older. But I think that feeling good and comfortable in my own body has helped.

That's not to say I'm in perfect shape. I still eat too much. My stomach still sticks out a little, though it's not as big as it used to be. I know I should work out for longer, more often. But overall, I feel a lot better now, physically and mentally, at the age of 46, than I did in my late 20s and early 30s.

What to do if you join a gym

Everybody has a preferred way to exercise - the point is to do it.

I like going to a gym because it's a separate location away from my home and because it forces me to devote a short period of time to real, intensive exercise. I can tell myself I'm going to do a big hike this weekend, or walk up the mountain behind my house every few days, but in reality I'll probably loaf it or find reasons to skip it.

So - if you decide you want to join a gym, here's my advice. (Note: I'm not a fitness expert, and some people will probably disagree with some of this, but it's what I've learned from experience, reading, and talking to trainers.)

• You're there to exercise - so get to it! If you're not exercising, you're not getting in shape, no matter how much time you spend at the gym. It's easy to waste time in the locker room, in the pool (swimming is low-impact exercise unless you're racing or training to race), in the steam room, sitting on the stationary bike, watching CNN or ESPN, looking at your phone as you sit on one of the weight machines, resting between sets, and on and on. Be moving all the time. Rest after you're home.
• Stretch, but don't waste too much time on it. You need to stretch a little bit, especially if you're about to work a muscle group you've been neglecting - you don't want to pull a groin muscle, for instance. (I've done it; it's awful.) But a couple of minutes is fine. Don't stretch for 15 minutes as a way to procrastinate.
• Forget the bike. It's fun to ride the stationary bike and catch up on your magazine reading, but it's not a workout. If you're using a machine, the cross-trainers and StairMasters give the best workout, as long as you're actually moving on them and pushing yourself, not just going in slo-mo. You can do 15 minutes on them with productivity equal to an hour on the bike. Intensive classes are also great, if you're into them. (I'm not.)
• More weights, less cardio. Cardio is important when you're first getting in shape and vital if you're starting to train for a big event like climbing Mount Rainier or running a marathon (so I've heard - I've never done either). But once you're in decent shape, a 15- to-20-minute burst of high-impact cardio is all you really need. Spend the rest of your time on the weight machines or, better, using free weights. Pushing against resistance builds strength, and building muscle increases your metabolism so you burn more calories at rest - even when you're not at the gym.
• Mix up the weights. You can balance between lots of reps with little weight (which builds stamina) and fewer reps with as much weight as you can handle (which builds strength). Mix it up. Work different muscle groups, in a different order, each day. If one muscle group starts to burn a little, you're doing it right - but take a break the next day to let the muscles heal and build up.
• Try classes. A lot of people find that joining a class - Pilates, yoga, step, whatever - or signing up with a personal trainer is the most reliable way to get out of the house and to the gym. Once you're there, you can do other things when the class or session is over.
• Leave your phone in your pocket. You might use it to listen to music, but resist the temptation to check email, Twitter, Facebook, or whatever your vice is. (Full disclosure: I fail at this way too often.)
• Anything is better than nothing. Woke up late? Had to work late? Only time for 30 minutes instead of the usual hour? Go anyway. Don't let zero exercise replace an imperfect workout.
• Don't quit. That's the hardest and most important thing. If you're in crummy shape, the way I was when I started, the first six months will be brutal. You'll wonder why you're bothering. It will seem hopeless. Just get out of bed and keep going. At a certain point, it will become a habit and you'll wonder what you did with that time before. After that, you'll start looking forward to it.

Happy new year!