How many miles do I need to ride in training to be ready for my event? I get asked some variation of that question all the time from cyclists getting ready for a century, gran fondo, gravel grinder, or endurance mountain bike event. Do you need to ride 60 or 75 miles during a training ride to be ready for a 100-miler? Does the length of my longest single training session matter?
Yes and no. There is nothing magical about achieving a specific percentage of the race or event distance in a single training ride. Marathon runners religiously use a 20-mile training run as a marker of preparedness to complete the event. Some cyclists and coaches insist on completing a 75-mile training ride in order to be ready for a century. Both are approximately 75% of the total event distance, but neither makes a significant difference in finish rates. So, then, what does make a difference?
Fitness trumps mileage
The development of your aerobic engine matters more than the miles you have in your legs. You can absolutely develop the fitness necessary to complete a challenging century or gran fondo with training rides that never exceed 3 hours. This is an important point for many cyclists who feel that longer events are out of reach because of limited training time. Cycling is a non-impact sport and you have a wide range of gears, so the physical capacity necessary to ride for 12 hours is not that much greater than it is to ride for 3 hours. As a result, with focused training within the time you have available you can develop the aerobic fitness necessary to successfully complete a 6-12 hour event. Would you go faster if you had more time to devote to training? Sure. But even with more time available for training, very long individual training rides are a very small component of what would make you faster.
The vast majority of your cardiovascular fitness and power output results from your shorter training rides. This is where you’re doing intervals that apply specific stress to energy systems and create a training stimulus. Relatively short and medium-distance group rides also build fitness because everyone in the group can maintain a higher power output and keep the group’s speed higher. If you’re preparing for a long endurance event and have limited training time, the best thing you can do is use your shorter rides to increase your power at lactate threshold and VO2max. Aim to go into your event with the highest fitness possible so you are better armed for the battle against the distance.
What very long rides do and don’t do for you
Individually, one very long ride (4-8 hours, depending on your fitness and experience) doesn’t impact your fitness or power output very much. The primary benefits from long training sessions are experiential. They are important for developing good fueling and hydration habits, for developing mental toughness, for learning how to pace yourself, and for physically adapting to sitting in the saddle for a long time.
For a lot of people reading this blog who are long-time cyclists, particularly those who are coming back from a period of diminished fitness or time away from the bike, the most important of these benefits will be reconditioning your backside for long hours in the saddle.
A side note about bike fit
Along the lines of physically adapting to long miles, keep this in mind: If you typically ride 1-3 hours you should expect some discomfort at the end of a ride that is 2x (or more) longer than normal. It doesn’t mean you weren’t fit enough for the ride or that there’s something wrong with your bike fit. When you dramatically increase your time on the bike, whether in one ride or in a block of training, there will be discomfort even when your bike fit is perfect. If you’ve been riding that position comfortably for months or years, don’t change it because you were stiff or sore at the end of a long ride. The ride caused the discomfort, not the bike fit.
When big rides cause problems
When athletes ask me how long their long ride needs to be in order to be ready for a big endurance event, I tell them it should be as long as they can realistically fit into their training schedule. The downside to big rides is that they require a lot of recovery, but don’t individually improve your fitness all that much. So, when an athlete with limited training time schedules too many big rides, those rides can actually get in the way of more purposeful training that would have a greater positive impact on fitness and power output.
In the end, go big when you can because big rides are fun and challenging and great learning experiences, but don’t stress about the length of your longest pre-event training session because that ride only plays a small role in your overall fitness.
CEO/Head Coach of CTS