- - How to Train for a 100 Mile Off-Road Race

How to Train for a 100 Mile Off-Road Race


article by Taylor Thomas

For many endurance athletes a 100-mile off-road  bike race is either a bucket list event, or the capstone of their season. This distance takes both mental and physical training to properly prepare. The appropriate balance of endurance training and specific race preparation is important to ensure success. You’ll want to start at least 28 weeks out from your race so as to have plenty of time to effectively integrate the three key periods of training. Base, build, and specialty phases will allow you to gradually build your endurance, threshold, and anaerobic capacity so that you’ve prepared all of your body’s systems for the event.

The start of your race prep will be the base training phase. This period, depending on your current level of fitness, should last approximately 12 weeks. During the base period the focus should be on building a strong aerobic base. Having solid endurance to build upon is critical for a successful 100-mile race. It’s during the base period that you’ll want to perform longer sub-threshold efforts to push your aerobic capacity. This is also a good time to integrate strength workouts into your training to help with injury prevention as you begin to gradually increase your volume and intensity. Remember that this is not the time to do hard anaerobic efforts, that time will come, but rather think of it as the foundation on which your successful season is being built. A couple of go-to workouts during your base period are:

Sweet Spot Interval – 20 minute warm up in zones 1 & 2. Then perform 30-45 minutes in your sweet spot (90%-95% of threshold). Finish the ride in zone 2.

Aerobic Threshold – 20 minute warm up in zones 1 & 2. Then perform 30-45 minutes at the top end of your zone 2 range. Finish the remainder of the ride at endurance pace.

After a solid period of base training it’s time to begin your build phase. This phase of training should last 8-10 weeks and is focused primarily on increasing your threshold and anaerobic capacity. Depending on what race you’ve selected, and the course profile, this period will look a little different. If it’s a race like Leadville that includes long service road climbs and lots of pedaling you’ll want to include longer more sustained threshold efforts. If it’s a race like the High Cascade 100 you’ll want to focus not only on sustained power but also leg strength and shorter max effort durations. Typically for most 100-mile races I like to have my athletes focus on raising their FTP and sustained power. Higher FTP allows for greater power during the inevitable long climbs and tempo work for the flats and more pedal-centric sections. During this period of training I also like to continue to include one day of specific strength work each week. This helps to build the athlete’s explosive power as well as strengthen connective tissues and muscles to aid in injury prevention. Use the specifics of the course to dictate exactly the types of workouts you’ll be doing. A couple of my favorites are as follows:

Threshold Ladders – 15 minute warm up in zones 1 & 2. Then 3 sets of 1 minute at max effort, 3 minutes at 15% above threshold, 5 minutes at threshold. Recover for 5 minutes in zone 2 between each set.

Over Under Surges – 15 minute warm up in zones 1 & 2. 4 sets of 5 minutes in zone 4, 1 minute at 120% FTP, then 5 minutes in zone 4. Recover for 5 minutes in zone 2 between sets.

The final stage of your race preparation is the specialty phase. During this phase lasting 8-10 weeks you’ll hone in on racecourse specifics. This is the time period when I like to apply any takeaways from analyzing the course profile to the workouts. Short punchy climbs require more short burst strength and the ability to recover quickly. While long climbs require sustained power and higher thresholds. There are probably elements of all of these in a given race so it’s up to you and your coach to develop a plan that properly prepares you for your race. This is also the time period where spending time on your mountain bike is vital. You’ll want to not only dial in your equipment, but also simulate the wear and tear on your body that only mountain bike rides can provide. Spending time on the trainer and your road bike are fine during the base and build periods, but try to get all of your long rides done off road. Save the trainer for specific workouts and inclement weather. This is also a good time to work on your bike handling skills if it’s an overly technical course. As you fatigue over the duration of the race it’s important to feel confident in your ability to deal with technical terrain.


Although you’ve been training for upwards of 20 weeks at this point you’ll want to keep the volume high during this period. There are no replacing long days on the bike as you prepare for what’s sure to be a full day in the saddle. Something else to consider is a tune-up race approximately 4 weeks out from your 100-miler. While this race shouldn’t be 100 miles it should be an off road endurance race that will give you a chance to see how your training is stacking up, as well as dial in your nutrition and equipment. Before you get too deep into this segment go ahead and build in a proper taper. It’s different for every athlete but the goal is to see no more than a 10% decrease in CTL and a TSB of +15 to +25. Hitting these landmarks by race day will help to make sure your body is properly rested and prepared for your race. Try these workouts during your specialty phase to fine-tune your fitness before the big day.

FTP Intervals – 20 minute warm up in zones 1 & 2. Then complete 3 sets of 8-12 minutes at threshold with a 2-minute recovery in zone 1 between sets.

Off-Road Ride w/ Tempo Finish – Ride at endurance pace for 2-3 hours off road, then during the last 30-45 minutes of your ride increase your effort to 80%-90% of your threshold.

Whether it’s your first 100-miler, or you’re a seasoned pro, this distance requires careful training and preparation. Take into account your current level of fitness, goal race, and goal time to build the right training plan for you. Not only will you need the endurance to cover the distance, but the strength and stamina to make it up the long climbs and steep technical sections that the course is sure to throw at you. Don’t rush your training. Spend the appropriate amount of time in each phase and focus on what workouts will get you to your goals. Much like the race itself, the training is not a sprint but rather carefully calculated to help ensure that you’re ready and able to conquer 100 miles.

Taylor Thomas is a dedicated endurance athlete with over a decade of experience as a competitive cyclist. He’s been involved in all facets of the sport, from working professionally with top brands like Trek and Specialized, founding race teams, organizing events, and personally competing at all levels. His racing background includes road, cyclocross, triathlon and ultra endurance events that push the body and mind to their limits. Taylor enjoys sharing what he’s learned as a pro mountain biker with his athletes to help them achieve their goals. As a USAC and Training Peaks Level 2 certified coach he’s gained not only the scientific knowledge, but the real world knowhow necessary to help athletes balance life and training. When he’s not on his bike he can be found on long trail runs or rock climbing in the mountains with his wife and dogs.

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