Treadmill Marathon Challenge

Workout - Treadmill Marathon Challenge

• 10min @ 6'15''/km
• 8 lots of:
  • 5.0km @ 5'00''/km
  • 2min rest
• 2.2km @ 5'00''/km
• 7min @ 7'30''/km

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Intro: This is a breakdown of We ran a MARATHON on a treadmill (very hot!) by This Messy Happy. The video’s worth watching in full — we’ve pulled out the essential takeaways so you can give this workout a shot yourself.

Key Points:

• The runners completed the marathon as a series of back-to-back 5 km (5 k) treadmill segments, trading off as each partner finished their leg.
• The indoor setup amplified the heat considerably—without a fan, heart-rate zones spiked faster than anticipated (zone 2 slipped into zone 3/4 quickly).
• A 5-minute km pace (≈12 min / mile) works reasonably well outdoors but presented a stiffer challenge on the belt.
• Water intake became non-negotiable—stepping off to hydrate was essential for staying in control and avoiding bonking.
• As the miles accumulated, mental toughness and settling into a steady rhythm made the closing blocks feel more manageable than the opening ones.

Workout Example:

1. Begin with 5 minutes of easy running to warm up.
2. Run 5 km at approximately 5 min/km (adjust to match your fitness level).
3. Once you finish the block, hop off quickly to drink, then hand the treadmill to the next person so they can resume.
4. Continue swapping 5 km blocks until you’ve covered roughly 42 km total.
5. Should your heart rate climb past your zone 2 threshold (around 164 bpm for this video) or a side stitch develop, take a walking break, rehydrate, and restart when ready.

Closing Note: Try constructing a marathon of your own by breaking it into 5 km chunks, tracking your heart rate, and drinking enough—then celebrate when you cross the line! The Pacing app makes it simple to dial in your target speeds and rest intervals for where you’re at right now. Get out there, embrace the challenge, and enjoy the process! 🎉

References

• We ran a MARATHON on a treadmill (very hot!) - YouTube (YouTube Video)