I knew the Apple Watch would help me improve my health, but I didn't quite understand how much until recently.

True confession: I've never jogged or run in my life. Well, at least not since physical education was a required class in my high school. I've spent the bulk of my 45 years on this planet sedentary. The Apple Watch is changing that, though. Now I'm training to run a 5K, and the Apple Watch is helping.

OK, it isn't just the Apple Watch that's helping. I turned the corner on my own health last year. I got gastric bypass surgery in November and have dropped about 100 pounds since then. I'm physically active every day, too. I try to do at least 30 minutes of cardio in the morning, and I've recently added some strength training to the mix.

Until June, I was content to make that cardio workout a brisk walk around my neighborhood. I'd get back to the house feeling accomplished. Sometimes I'd even be breathing a bit heavy or have some light sweat on my brow. Yay me!

A few days after I got my Apple Watch in June I noticed something: It wasn't tracking my outdoor walks as actual physical activity at the same rate as I was. I might log 30 minutes in an outdoor walk, but only 15 or 20 of it would actually get recorded in the green Activity band.

At first I wrote off the discrepancy to watchOS 1.x bugs, but then I began to realize something: The Apple Watch is cleverer, or at least less self-deceptive than I am: It only counts physical activity if the wearer legitimately gets his or her heart rate up. As far as the Apple Watch was concerned, I was could have just been walking around the house for much of those walks. I may have been exercising, but I wasn't exercising exercising. The Apple Watch knows the difference.

This has provoked me push myself more on these morning walks of mine. A few weeks ago I thought to myself, "Hey, maybe you could try jogging a bit instead of just walking."

I did. Just for about 30 or 45 seconds. Far enough to know that I could do it, and that I didn't start dry-heaving or spurting blood. Then I started adding a few brief jogs to my walk each morning. I'd come back from my morning circuit breathing much heavier than I was before. And the Apple Watch has rewarded me by counting that activity more.

I belong to a bariatric patients support group on Facebook, and some of the other members have participated in 5K races in the past. I've never run a road race in my life. Never imagined I would be able to.

Well, a week and a half ago I downloaded Couch to 5K, an app that helps you get off your duff and into a 5K race. It's a nine-week process, so I'm hoping that I'll be ready for a 5K some time in the fall.

I'm happy to report that the Couch to 5K app sends reminders to the Apple Watch, so when I'm using it, I'll get tapped to tell me to walk, jog, and cool down. That means I can leave the phone in my pocket where it belongs.

The increased activity level is something that the Apple Watch has noticed, too, because each week the Activity app takes stock of what I've done and makes a suggestion for my daily goals. This week it recommended that I move my calorie burn goal up about 10 percent from where it was last week. The achievements are silly virtual medals, of course, but it still feels good, and I'll be darned if it isn't actually motivating me to do better.

Obviously the Apple Watch doesn't make me get up off my posterior and move. That's entirely up to me. But its gentle encouragement and its fantastic integration with the apps I'm using make it an ideal workout partner that I'm really happy to have.