Travelling in Denmark this week brought a unexpected highlight: signing up for the local Half Marathon in Aalborg. Stepping up to the start line at 9:01 AM, the conditions were practically tailor-made for running — a fresh 18°C breeze, 84% humidity, and a scenic course winding along the Limfjord coastline.
The overall result: 21.19 km in 1:53:31 (average pace 5'21’’/km), with an average heart rate of 154 bpm and a steady cadence of 190 spm.
5K Split Breakdown: The 15km Divide#
Looking at the 5K Splits card in Apex Run, the story of today’s race splits neatly into two distinct halves:
- 0–5 km (25:59 | 5'11’’/km | HR 155): A smooth, easy start settling into the coastal breeze. Body felt light and rhythm clicked in quickly.
- 5–10 km (25:49 | 5'09’’/km | HR 156): The fastest 5K block of the day. Locked into a steady cadence (190 spm) and enjoying the scenic fjord views.
- 10–15 km (26:14 | 5'14’’/km | HR 154): Still holding solid rhythm and sub-5:15 pace. Cardiovascular stress remained remarkably stable around 154 bpm.
- 15–20 km (27:53 | 5'34’’/km | HR 154): The turning point. The legs started feeling heavy. Notice that heart rate didn’t spike (still 154 bpm)—meaning this wasn’t a cardiovascular engine failure, but pure muscular fatigue in the quads and calves catching up.
- 20–21.19 km (07:33 | 6'19’’/km | HR 159): Tackling the steep final climb! Looking at the elevation profile on the share card (total climb 179m), the course features a sharp uphill rise right before the end. Digging deep into Zone 4 effort (HR pushed to 159 bpm) to push up the hill and cross the finish line.
The Sightseeing “Tax” & Final Climb#
Why the pace drop after 15 km despite perfect 18°C weather and stable heart rate?
The main culprit was clear: 26,000+ daily walking steps. Spending the past several days exploring Denmark on foot meant clocking over 26,000 steps every day leading up to race morning. While cardiovascular recovery stays high during vacation, muscle endurance takes a quiet toll. By kilometre 15, those accumulated walking miles made their presence felt, and the final steep hill climb provided the ultimate test!
Final Takeaway#
Even with the late-stage pace drop, Aalborg delivered a fantastic race experience. Running alongside the water in cool Nordic air, holding 86% of the run in Zone 3, and finishing a half marathon in 1:53:31 while on vacation makes for a memorable running!
Previous log: August 8 LSD — 21.44km in cool post-rain air and merging split FIT files.