How I Shaved Nearly 3 Minutes Off My Half Marathon Personal Best

Like any other runner, I love beating my personal best every now and then. My Half Marathon PB has remained unbeaten since 2021. Back then, during the Bucharest Marathon, I ran the half marathon in 1:44:45 — a result that marked significant progress for me at the time.

I vividly remember that day. It was cold, and I wore tights and long sleeves. My watch died after just 2 kilometers, leaving me to navigate the race without it. I started by following the 1:50 pacers but soon found them too slow, so I pushed ahead to catch the 1:45 pacers.

However, the 1:45 pacers seemed to have miscalculated their pace, finishing at least two minutes faster than expected. By the time I crossed the finish line, I couldn’t see them anywhere — they were well ahead. Despite the chaos, my strategy of staying ahead of the 1:50 pacers worked. I walked away with a personal best that took me three years to beat.

A PB Too Far Away

Over the next few years, I kept training and logging the miles, trying to surpass my PB. Yet, on only two occasions did I even come close — finishing at 1:45:35 and 1:45:34. Breaking 1:45 felt impossible. I even started doubting whether the timing or distance in my 2021 race was accurate.

I analyzed my training from 2021, comparing it to recent years. What stood out?

For short intervals (100m, 200m, 300m, 400m) and long intervals (800m, 1k, 1.2k, 1.5k, 2k), my current pace was faster than in 2021. Yet, I remained far from my PB. It felt like a mental block. Perhaps running with a watch was holding me back — making me overly cautious and subconsciously slowing down.

Another key difference was my weekly mileage. In 2021, I logged between 40–45 km per week, whereas my current training ranged between 35–40 km per week.

Determined to understand what influences Half Marathon performance, I began researching how to optimize my training.

What is More Effective for Half Marathon Training?

I reviewed countless training plans, eventually realizing I had neglected one key type of workout: tempo runs. Other than that, I had been diligent — doing speed workouts (both short and long), alternating long runs with progression runs, and including at least one easy run per week.

Still, something felt off. I stumbled across a fascinating study titled “Interactions between monthly training volume, frequency, and running distance per workout on marathon time.” The study analyzed data from 1,001 recreational runners who completed the 2017 Rotterdam Marathon or Half-Marathon, including 376 half-marathoners.

The findings revealed three main factors influencing finish times:

Weekly Mileage:

• Below 20 km/week: Insufficient training volume.
• 20–32 km/week: Baseline group for comparison.
• Over 32 km/week: High-mileage runners performed significantly better.

Longest Endurance Run:

• Below 15 km: Relatively short long runs.
• 15–20 km: Baseline group.
• Over 20 km: Runners with longer long runs performed better.

Training Pace:

• Slower training pace (>6:00 min/km).
• Moderate pace (5:30–6:00 min/km): Baseline group.
• Faster pace (<5:30 min/km): Correlated with faster half-marathon times.

Findings for Half-Marathon Runners

The study confirmed that runners with:

• Higher mileage (above 32 km/week) achieved faster finishing times.
• Longer runs (over 20 km) had better results than the baseline group.
• Faster training paces (<5:30 min/km) improved performance significantly.

In other words: run more, run longer, and run faster. You might think, “No kidding!”

My Changes

I decided to make three adjustments:

1. Increase my weekly mileage to 45 km from 35km.
2. I extended my long runs from 15 km to 18 km.
3. Incorporate some once-per-week tempo run of 3, 5, or 7 km.

Some weeks, I even logged 47–49 km. I also added tempo runs to my schedule. Reviewing my data on Runalyze, I noticed my monthly average pace improved slightly — from 6:13 to 5:55. While not dramatic, this includes warmups, cooldowns, and easy runs, so it’s worth monitoring over time.

The study also highlighted that runners with lower BMIs tended to perform better. Among the groups with high mileage, longer runs, and faster paces, the average BMI was 22 — a manageable goal for recreational runners.

What’s Next?

My next step is to increase my long runs to 21–22 km and monitor how this impacts my half-marathon times. I will also maintain a weekly mileage of 45–50km per week; if I behave myself during the winter holidays, I will try to reach a BMI of 22.

I will be finishing my Superhalfs series next year in April in Berlin, and I would love to have another PB.

Good luck and see you on the course!

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