Serious runners are probably going to laugh at this post because a 34-minute 5K isn’t exactly impressive

But let me give you some context. Maybe it’ll inspire someone like I once was to get off the couch and start running too.

In a previous post, I talked about hitting a low point in both mental health and physical fitness. At the time, I weighed 270 pounds and would get winded just walking to my car. I’ve also never been a runner (not even when I was younger). I ran a mile once in my life, back in middle school, just to complete the President’s Physical Fitness Challenge that was popular in the ‘90s. (I did it in 7 minutes and 40 seconds, but only once.)

I’ve always told people that I’m more of a walker. I’ve been an avid hiker (well, maybe not during those 270-pound, winded-walking days, but I digress). I could walk for miles, but I couldn’t run for more than 30 seconds. I’d get those awful side stitches, I couldn’t breathe, and my legs would turn to rubber pretty quickly.

When I decided to get back into shape, becoming a runner wasn’t even on my radar. I went back to what I knew: hiking. For the first few months, my weight loss efforts involved walking at all times of the day. When I hit my first plateau, I decided to return to the gym and start lifting again.

The idea of running didn’t come up until about a year into that gym routine. Part of my workouts involved two 15-minute stints on the elliptical—one to warm up and one to cool down after lifting.

At some point, the idea of running a 5K crept into my mind. But I guess I was still clinging to that younger version of myself, the one who thought, Hey, I’ve always been a resilient guy so how hard could it be?

Well, my first attempt was on a treadmill, and I quickly discovered just how hard it actually was. My legs got tired before I even got winded, and I got winded fast. The elliptical had helped me build some cardio endurance, but I hadn’t realized how much it reduced the impact on my legs.

Still, I stuck it out and finished 3.1 miles with a time of 52 minutes. Honestly, I probably could’ve walked it faster. There wasn’t much actual running involved. I just didn’t have the gas. So, I gave up on the idea for a while.

But as I continued to lose weight and get in better shape, the idea lingered in the back of my mind. Around fall 2023, I decided to replace the elliptical with treadmill running for my warm-up.

I made a goal: run for 15 minutes straight without stopping. I set the treadmill to 4 MPH—very slow, but still faster than my usual walking pace of 3.5 MPH.

Let me tell you, that first attempt was brutal. But I made myself stick with it for 15 minutes every gym session. After a few weeks, I bumped the speed to 4.1 MPH. Then 4.2 MPH. And so on.

To give you an idea of how gradually I progressed: as of May 2025 (a year and half later), I’m running at 5.6 MPH. I would stick with each speed for several weeks before nudging it up by just 0.1 MPH.

I reasoned that once I hit 6 MPH, I’d start increasing the duration. After all, if you want to complete a 5K in under 30 minutes, you need to maintain an average speed of 6 MPH. So that became my treadmill goal: build to that pace for that length of time.

But the more I learned about running, the more I realized that slow, steady runs aren’t the only way to improve. If you want to increase speed and endurance, you also need to include sprint intervals and incline runs.

Eventually, I listened to the audiobook Outlive by Peter Attia (fantastic book, by the way), and I learned about the concept of VO₂ max—the single greatest predictor of longevity among all health markers. If you want to live a longer, healthier life, you need to increase your VO₂ max.

In the book, he explains that the best way to do this is by spending 3–4 hours per week doing Zone 2 cardio, and then dedicating one day a week to sprint intervals. There’s a lot to unpack there—so let me walk you through what each of those are.

Zone 2 Cardio

Here’s a Mayo Clinic’s article on Zone 2 cardio if you want to read more about it. But essentially, Zone 2 is cardio performed at about 60–70% of your maximum heart rate.

To calculate your max heart rate, you subtract your age from 220. Then, to find your Zone 2 target range, you multiply that number by 0.6 and 0.7 to get the lower and upper bounds.

Here’s what that looks like for me:

I’m a 43-year-old male.

• 220 – 43 = 177 (my estimated max heart rate)
• 0.6 × 177 = 106 BPM (lower end of Zone 2)
• 0.7 × 177 = 124 BPM (upper end of Zone 2)

So for me, the goal is to keep my heart rate between 106 and 124 beats per minute. A brisk walk usually gets me into the lower part of that range fairly easily.

A good rule of thumb: you should be able to hold a conversation during Zone 2 cardio—maybe with a little effort—but you shouldn’t be able to sing.

Zone 2 training is most effective when done for 3 to 4 hours per week.

Sprint Intervals

The other part of the VO2 max story is doing sprint intervals once a week (also known as High-Intensity Interval Training (HIIT)).

One of the most popular forms of this is called 4×4 interval training. The goal is to push your heart rate to 90–95% of your max for four minutes, followed by three minutes of rest. This cycle is repeated four times.

In my case, with a max heart rate of 177, I calculate the range like this:

• 0.9 × 177 = 159 BPM (lower end)
• 0.95 × 177 = 168 BPM (upper end)

So my target range is 159 to 168 BPM during the intense intervals.

I’m definitely not in shape to handle that yet, but I’ve been doing a modified version that I call the 4×2 interval. Basically, I run at 7.3 MPH on the treadmill for two minutes, then walk at 3.5 MPH for two minutes. I repeat this four times.

Conclusion

As you can see, my journey from being overweight to running a 34-minute 5K has been a long, winding road. If you’re hoping to become a runner, the most important thing is to go at your own pace. The old saying “This is a marathon, not a sprint” has never felt more true.

The hardest part for me was learning how to pace myself in a 5K so I wouldn’t burn out too early. That meant running slower than I wanted to when I first started. I also learned that form and gait really matter. For example:

• Slightly leaning forward while running helps with momentum.
• Lightly touching your fingers together—as if you were rubbing a penny—helps keep your arms and upper body relaxed, saving energy.
• And don’t underestimate the power of a good pair of sunglasses—seriously, it helps.

At the end of the day, the goal is simply to improve your physical fitness a little bit at a time. You don’t need to run a 5K next week. Maybe you just start like I did—at a pace just above walking—and slowly build from there.

Because ultimately, your fitness is your business, and you’re only competing with one person: your past self. And that’s a race you’ll always win if you’re willing to put in the work.