How to Complete the 100K Erg Challenge

By the Watta Team · Updated

The 100K erg challenge — rowing 100,000 metres in a single session — is the ultimate test of endurance, mental toughness, and preparation. Taking 6-10+ hours, it demands meticulous planning around pacing, fuelling, hydration, and comfort. This guide covers everything you need to finish the distance.

Understanding the Challenge

One hundred thousand metres on the erg takes approximately 6-10 hours depending on fitness and pacing. It is more than twice a marathon distance and requires fundamentally different preparation. The physical demands are substantial but manageable with correct pacing — the real challenge is mental. Boredom, discomfort, and the desire to stop are your primary opponents. Many who attempt 100K have the fitness but lack the preparation for the non-physical elements.

Training Build-Up

Preparation should span 16-20 weeks. Build your longest single session progressively: start at 60 minutes, add 15 minutes per fortnight until you reach 3-4 hours. You do not need to row 100K in training — reaching 50-60K in a single session is sufficient preparation. Supplement long rows with regular 40-60 minute steady state sessions 3-4 times per week. Total weekly volume should peak at 80-100K metres before tapering.

Pacing and Execution

Pace conservatively — your 100K split should be 20-30 seconds per 500m slower than your 2K pace, or your comfortable UT2 pace. Start the first 20K at a pace that feels genuinely too easy. Settle into your target from 20-80K. Push only in the final 10-20K if you feel good. Break the distance into 10K segments and set a mini-target for each. Stop the erg for brief breaks (2-3 minutes every 20-25K) to stand, stretch, eat, and use the bathroom.

Fuelling, Hydration, and Comfort

You will need to consume 200-300 calories per hour from easily digestible sources: energy gels, bananas, jelly sweets, or diluted sports drink. Sip water every 10-15 minutes. Seat comfort is the biggest physical challenge — use a padded seat cover and wear cycling shorts. Apply anti-chafe cream to any friction points before starting. Set up a table within reach with all your nutrition, water, and entertainment.

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Mental Strategies

The 100K is a mental marathon. Use a combination of strategies: segment the distance (10 x 10K), set mini-rewards at each checkpoint, alternate between music, podcasts, and silence. Have a support person present if possible — even just someone checking in every hour helps enormously. Accept that there will be low points (typically around 40-60K) and that they pass. Do not make decisions about quitting during a low point — commit to reaching the next checkpoint first.

Tips

  • +Do at least two 3-4 hour training rows in the final month to test your fuelling, seating, and mental strategies.
  • +Prepare all nutrition and hydration before you start. Stopping to prepare food mid-row breaks rhythm and wastes time.
  • +Set up entertainment in advance — queue playlists, download podcasts, and have a backup plan if technology fails.
  • +Wear cycling shorts and use a gel seat pad. Seat soreness ends more 100K attempts than fitness does.
  • +Tell someone what you are doing. Accountability makes it harder to quit, and someone checking in at 60K is invaluable.

Further Reading

Frequently Asked Questions

How long does 100K take on the erg?
Most people complete 100K in 7-10 hours including brief rest stops. Very fit rowers can finish in 6-7 hours. Recreational rowers typically take 8-10 hours. The pace is comfortable — it is the duration that makes it extreme.
Can anyone do the 100K challenge?
Anyone with a reasonable aerobic base (able to row comfortably for 60+ minutes) can build toward 100K over 16-20 weeks. It is not about speed — it is about preparation, fuelling, and mental commitment. Walk before you run: complete a marathon erg (42K) first.
How do I recover from 100K?
Take 3-5 full rest days after the challenge. Light walking on days 2-3 aids recovery. Return to easy rowing after 5-7 days. Full training can resume after 10-14 days. Eat protein-rich meals, hydrate extensively, and expect significant fatigue for the first 48 hours.

Related Content

Marathon Rowing GuideHalf Marathon Rowing Guide10K Rowing GuideSteady State Rowing GuideDaily Erg GuideSteady State RowingSteady state rowing is continuous, easy-paced erging at conversational intensity for 20–90 minutes — the UT2 band, 55–65% of 2K power at 18–22 spm — used to build aerobic fitness.UT2 TrainingUT2 training is low-intensity aerobic rowing at 55–65% of 2K power — heart rate 60–70% of heart-rate reserve, 18–22 spm — and it forms the foundation of a rower's endurance fitness.Calories (Rowing)Calories on a Concept2 ergometer are calculated from watts (power output), not from heart rate or individual body composition, using a standardised formula.Heart Rate Zones (Rowing)Heart rate zones in rowing are five intensity bands based on resting and max heart rate, used to target different training adaptations.Split TimeSplit time is the pace expressed as the time it takes to row 500 metres on an ergometer, displayed in minutes and seconds (e.g. 2:00.0/500m).Rowing Pace CalculatorCalorie Burn Calculator5K Time PredictorFor Competitive RowersFor RowersFor Home GymMarathon Erg Protocol

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