The search phrase, “I’m strong on the road bike, weak on the mountain bike” led someone to my blog, and it’s an interesting – and quite understandable conunderum. It also falls under one of my favorite topics of discussion when it comes to conversation and posts… I love to compare one bike with another and contrast them as well because they’re all so interesting and different
First of all, in my humble opinion, technically being strong on one but not the other – strictly in terms of legs – is impossible. There just isn’t enough of a difference between the two, as far as pedaling goes. I’m also not going to bother with aerodynamics and tire difference, both of which are the two obvious factors that make a rider slower on a mountain bike… That’s low hanging fruit and they wouldn’t make a person weak on one but not the other.
There are a few simple reasons why someone (myself included) could be stronger on a road bike over a mountain bike and a few that really require a little bit of thought…and some push ups. Let’s start simple…and assume we all know that a mountain bike is slower than a road bike in the first place. We’d all like to buck the laws of Physics from time to time but in the end, it’s the law dude. Think of it as the US Constitution… Pretending it means something it doesn’t is a lot easier than actually changing it (think Second Amendment).
First is fit – if both bikes are fit exactly to the rider as they technically should then this almost would have no bearing, with two exceptions: There are some who say the mountain bike should be a little smaller than your perfect fit and I happen to agree with this line of thought. I like that my mountain bike is just a touch undersized because it allows me to throw the bike around a bit more in corners and over obstacles (stumps, rocks and roots). Also, and I’m not speaking from experience here, I’ve heard that 29’ers are a little harder to get rolling (but are easier to keep rolling) because of the size and weight of the wheels. Those two could contribute the the thought that someone is perceptibly stronger on a road bike because they will slow you down a bit more.
Also, the setup between the two is different. On a mountain bike, the rider is sitting in a much more upright position which means that you’ll be working the legs a little differently. I have noticed that I can feel a ride in the glutes a lot more after a ride on the mountain bike than the road bike. Assuming the obvious – that one wouldn’t expect to achieve the same speed on a mountain bike as a road bike, workouts on each bike do feel different.
Also, the surface that we’re riding on will have a lot to do with whether or not we feel strong on a mountain bike. This, I think would be the biggest factor. On a road bike, we’re cruising down the road on smooth pavement. If we’re riding on single track trails, there are a whole host of different factors that would tax the body more heavily – namely roots, rocks, mud, sand and ruts. Each requires a different method of handling the mountain bike. Add to that uphill and downhill slopes and the methods double. To keep this short, I’ll use sand for just one example – sand requires the rider to shift his or her weight back, usually to the very back edge of the saddle so the front wheel can be used like a rudder. If your weight is in the standard position or even forward, you’ll put too much weight on the front tire and it will sink in the sand. This works the same for a downhill slope but not a steep climb. If you’ve got your weight too far back and you’re in one of the easier pedaling gears you can easily flip the bike backwards – the granny gears provide that much torque. Now apply different principles to each of the obstacles and you realize – there’s a lot to mountain biking beyond just pedaling as hard as you can.
Finally, rolling over all of those obstacles takes a toll on the arms and upper body. You really have to be strong if you’re going to cruise the trails at a decent clip. I’m not (though I’m by no means a weakling) and I have a tough time over more than 20 miles. To say that arm, upper body and core strength are not important on a road bike wouldn’t be right, but all three are more important on a single track riding a mountain bike.
Taking the above factors into account, then adding in trail difficulty – take Michigan trails for instance which are notorious for quick direction changes and technical difficulty, include a bike that rides 25-30% slower on a flat surface anyway, and you could end up with the impression that you’re not as strong on a mountain bike – when you’re actually in the same place among your peers on both.
To wrap up, I’m above average “strong” in all three instances: Road bike, mountain bike on the road and mountain bike on a trail. I’m still 25-30% slower on a mountain bike on a paved road and 50-60% slower on a trail… But slower doesn’t mean weaker.