I Changed How I Balanced Strength and Mileage—and Ran 10 Minutes Faster Than Expected in My Half Marathon. Here’s How.

I’ve always been more of an anaerobic athlete, meaning I love shorter, faster running and strength workouts. In fact, I love strength so much that even during my first marathon training block, I enthusiastically committed to three heavy lifts a week.While strength training prevents injuries, makes you more durable, and can even boost your running economy, says Des Clarke, an RRCA-certified run coach based in Phoenix, I often spent evenings in the gym lifting weights instead of allowing my body to recover from 40-mile weeks.As I started training for a half marathon for the second time, I decided to put more of an emphasis on mileage. I didn’t want to nix strength from my schedule entirely, but I had to figure out how to dial back my time with the weights and increase my running time in a safe, balanced way.Doing so helped me run a 1:46:50 half marathon on a majorly hilly course. Here’s what I did to get there so you can strike a better balance, too.How I Increased My Mileage Safely Without Sacrificing StrengthFor anyone running half marathons and marathons (especially someone who’s newer to longer distances like I am), higher mileage weeks give you the base you need to run longer and faster.“If you want to get better at running, it is true that to a point, you need to run more,” says Clarke. “You’re building the aerobic capacity, strength, and durability that you need to run those distances without getting injured.” That looks like building volume incrementally over time, she says.Before I started half marathon training, I was running at least two times each week for about eight months. I was pretty consistent, but knew I could afford to add more miles. So before starting my plan, I added another day of running to my schedule, and then when I kicked off the first week, I tackled four days a week of running.I also added some more miles to my midweek runs. Last training cycle, I usually opted for four-milers, but this time, I bumped it up to five or six miles.Clarke typically recommends repeating the same weekly mileage for two to three weeks in a row to make sure an athlete has adapted to that particular load before increasing again. I did this during several weeks of my plan.In that same vein, it’s useful to take a deload week every three weeks or so to better absorb training gains, Clarke says. This involves scaling back your mileage by around 10 to 20 percent before returning to your typical volume. My training plan also included these, allowing me recovery time while pushing mileage.To balance this increase in mileage, I dropped to two lifting days per week instead of three, cutting down on volume (and consequently my overall time spent in the gym), which Clarke recommends. Last year during marathon training, I spent three days a week lifting weights for about an hour or more. This training cycle, I’ve spent 30 to 45 minutes lifting weights one to two times a week. I split up my usual hour-long routine into two separate days and alternated between them.How Swapping Strength Training for More Miles Paid Off1. I Actually Felt Recovered Going Into Every RunI remember how exhausting it felt to spend more than four hours a week strength training on top of 35- to 40-mile weeks during marathon training. Cutting my time in the weight room in half each week (from three hour-long lifts to two 45-minute lifts) not only allowed me to fit in a few extra miles but take my recovery more seriously, too.When it came time to run a Wednesday track workout, for example, I felt fresh and ready to tackle the intervals with more energy. My two-mile warmups always felt doable and I didn’t dread the speed or feel like I was running on tired legs.2. I Had More Energy Outside of RunningMy mood and energy levels changed a lot outside of my runs, too. I noticed that during and after my recovery days, I went to work feeling a lot more focused, happy, and engaged in social activities.As a result, I felt more refreshed and excited to return to each run—a feeling I didn’t have in my previous training cycle, even when running fewer miles per week.3. I Ran Faster Than ExpectedBefore I started training, I planned on aiming for a sub-two-hour half marathon. But after talking to a run coach who believed I was capable of running faster, I decided to aim for something around the 1:45 to 1:50 range instead, about 10 minutes faster than what my goal would’ve been initially.I ended up finishing a mere few seconds away from my half marathon PR (done on a much flatter course) and felt smooth through every mile.I also tackled some of the best pacing I’ve ever accomplished: I started out with the 1:50 pacer and naturally moved up after the first three or four miles, averaging an 8:10 pace overall, even with multiple hills throughout the race.Kristine Kearns, a writer and avid runner, joined Runner’s World and Bicycling in July 2024. She previously coached high school girls cross country and currently competes in seasonal races, with more than six years of distance training and an affinity for weightlifting. You can find her wearing purple, baking cupcakes, and visiting her local farmers market.