After eight days of hard training and suffering, you might find yourself wondering what sort of fitness returns you can expect from our annual 8DC challenge. To shed some light on this matter we’ve formulated a brief breakdown of the workouts themselves, the overall structure of the entire painful affair, and the all-important description of why – outside of stubborn, obsessive masochism – you gutted it out, day after day, for eight straight days.


Workout Structure

Each workout intentionally bared similarities to the concurrent bike race taking place in The Golden State on that same day, but each day’s workout clearly had to be scaled down in terms of volume & stress. This is not to say that any of these workouts were anything short of their own, standalone challenges though.

Each workout pushed the Intensity Factor way up toward its highest extent while still keeping things achievable – on paper anyway – such that you could routinely bury yourself, but not too deeply to come back the next day.

This was achieved via variety in the efforts themselves and by offering appropriate, though seldom, generous levels of recovery based on the efforts preceding each bit of “rest”.

But bike racing is an unforgiving sport that relies of the ability to work hard, really hard at times, yet keep coming back for more & more…and more.

So through a combination of intense sprints, brutal ascents to mountaintop summits, extended endurance efforts and virtually no downtime, your fitness was addressed on virtually every level, every day.

Challenge Structure

Again, the order of each stage was based on parcours developed by race organizers outside of TrainerRoad, so the structure was less about addressing specific fitness elements as emulating the unpredictability and often unrelenting nature of mass-start bike racing and spectator-approved course design requirements.

With that said, simply surviving each day and rallying for the next can’t help but improve everything from your peak power production capabilities, i.e. sprinting, to your anaerobic capacity when the efforts went – and very often remained – well above FTP, all the way down to basic aerobic engine adaptations inherent in lower-intensity work.

This is all to say, if this challenge didn’t break you, it will almost indefinitely make you stronger (given proper recovery afterward). And if it did break you, you’re still likely to see improvements, again, following proper & adequate recovery.

Fitness Gains

If you actively addressed your limiters and forced yourself of take part in all of the aspects of each day’s workout, you’re amongst those riders who are likely to see the most measurable and impacting gains.

If, on the other hand, you opted for more of a… conservative approach and perhaps didn’t indulge every whim each course thrust upon you, there’s not much reason to expect improvement in those areas you chose to bypass.

But assuming you hung in there and conquered, or at least sincerely attempted, each surge, sprint, time trial, paceline, attack, too-short recovery and everything else we threw at you, it’s safe to say your overall fitness will grow as you benefit from numerous improvements in the weeks ahead.

Given adequate recovery ranging anywhere from a few days to a few weeks depending on your level of experience and fitness, it’s realistic to see measurable improvements in aerobic endurance (thanks to everything well below FTP), muscle endurance (thanks to efforts close to your FTP), peak aerobic power (thanks to efforts 10-20% above FTP), peak anaerobic power (thanks to those short brutes upwards of 120% FTP), and your neuromuscular power (thanks to the myriad sprints littered throughout).

What Now!?

Having endured the massive amount of work you just faced, it’s now time to take your recovery equally as seriously. And while this is a very subjective aspect of training – much like all of it – in the way that some athletes bounce back more quickly than others, it’s still safe to assume that all riders completing 8DC are due for a few easy days of riding and/or time off the bike.

Remember, training is all about chasing fitness adaptations and those adaptations happen during rest. So give your body a chance to adapt, to soak up the copious amounts of stress you just heaped on it, and to bathe in the eventual rewards of improved fitness.

Well done, Everyone. Rest up, get back to training in due time, and we’ll see you all next year.



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Jonathan Lee

Jonathan Lee is a Level II USA certified cycling coach and the host of the Ask a Cycling Coach podcast. His background in the sport of motocross has translated into a passion for cycling, mountain biking and all things training. If you have a training question, submit your question for Jonathan to answer on the next episode of TrainerRoad’s podcast.

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