8km Brisk Walk at 9:05/km: Why Walking Is Serious Aerobic Exercise
An 8km walk at 9:05/km with an average heart rate of 120 bpm shows that walking can be much more than gentle exercise. A controlled, sustained pace can provide a substantial aerobic workout.
There is a tendency to think of walking as something you do when you are not exercising properly. But an 8km walk at a brisk pace tells a rather different story.
This morning I covered 8.0km in 1 hour 12 minutes 44 seconds, averaging 9:05 per kilometre. My average heart rate was 120 bpm and my maximum was 132 bpm, with 64 minutes recorded in the aerobic zone.
A remarkably steady pace
The kilometre splits show just how controlled the session was:
- 1km – 9:43
- 2km – 8:54
- 3km – 9:10
- 4km – 8:57
- 5km – 9:08
- 6km – 8:54
- 7km – 8:55
- 8km – 9:02
The first kilometre was deliberately slower, but after that the pace settled into a very narrow range. Six of the final seven kilometres were between 8:54 and 9:10 per kilometre.
That is not a casual stroll. It is a sustained, brisk walking pace that can be maintained without needing to run.
Keeping the heart rate under control
The most interesting figure for me was the heart rate.
An average of 120 bpm for more than 72 minutes, with only one minute recorded as anaerobic, shows that the session remained predominantly aerobic. There was no need to turn the walk into a hard workout to get a meaningful training effect.
The combination of distance, duration and controlled heart rate is what makes this type of session useful. It provides a substantial amount of aerobic work without the same impact and intensity associated with continuous running.
Walking does not have to mean slow
There is a big difference between wandering around for a few minutes and deliberately walking at a brisk, sustained pace.
At around 9:00/km, an 8km walk takes more than an hour. That means plenty of time spent moving continuously, while still keeping the intensity under control.
It also fits well alongside running and walk-jog training. Instead of every exercise session needing to be hard, a brisk walk can provide useful aerobic volume while allowing the body to work at a more manageable intensity.
The bigger picture
Today’s session burned a recorded 624 calories and produced 64 minutes of aerobic activity. More importantly, the pace remained remarkably consistent once the first kilometre was out of the way.
That is something I find increasingly interesting about walking. You don’t necessarily need to run to produce a worthwhile endurance session. Increase the pace, keep moving and extend the distance, and walking can become a serious piece of aerobic training in its own right.
8km. 72 minutes. 9:05/km. Average heart rate 120 bpm.
That’s a pretty good workout from a walk.
