This year will be my second go at the Silver Rush 50, which starts with a 100 yard run w/ bike up a sledding hill that seems pretty close to a 100% grade.
Last time I started in the second row, went hard but not all out, and went across the timing mat in ~10-12th, and I wasn’t very fit that year. 1st across the mat get a Leadville entry.
This year I’m gonna try to be that guy.
99% of people push their bike, but it seems like physically speaking, one is doing the same amount of work whether pushing or carrying, but pushing adds in rolling resistance, so I’m gonna be the odd man out and shoulder my bike.
Do you have to cross the mat with your bike? Leave it at the start, take your number plate only and sprint! Then walk back and grab the bike to finish out the race.
Pushing is more efficient in the long run, but if you want to win the sprint up the hill, carrying is better. When carrying, it’s easier to get in a balanced running rhythm and can move faster. Pushing has you off balance.
In my first Silver Rush, I ran too fast up the starting hill, spiked my HR and took the next hr+ to get back under control.
Carrying adds about 10kg of weight to you. Pushing adds only rolling resistance. You think that’s the same work?
Pushing is easier. Carrying makes sense when you either want to keep the bike of the ground (mud, sand), or if it is very uneven (rocky tracks, steps, things to climb over). Dealing with uneven ground is easier just on your feet.
In terms of pure theoretical physics. Pushing doesn’t only add rolling resistance. In both cases you are moving the weight of yourself + bike + any gear up the slope. In both cases, you are still putting in the required energy to move the weight of the bike up the slope.
In terms of “amount of work”, It would actually be better to carry the bike like, the topic starter said, because there would be rolling resistance added when pushing the bike.
However, the rolling resistance of a unloaded bike at such low speeds is very minimal and I think it will not impact your actual speed running up.
Like others have said, you should probably just time both on a local (short) hill with a similar gradient. If running with the bike schouldered allows you to be in a more forward and stable position, it will probably be faster. Or if you find that leaning on the handlebars benefits your balance, then that would probably be faster.
You are moving yourself and the bike up the slope. But if you push, you are not carrying the weight. The ground carries the weight of the bike. Otherwise you have to add the energy that it costs to keep the bike lifted up above the ground for the amount of time it takes to get to the top of the hill. (Humans are not rigid bodies. Keeping a load lifted requires continued use of energy to feed our muscles etc. )
Imagine the bike was a motorbike. Would you rather push or carry it up a slope? Or even push or carry along a flat road?
I agree with you.
You’re first post made it seem that there was only rolling resistance to overcome, and nothing more when you push the bike.
So yes, lifting the bike requires constant energy from your muscles. Even if the theoretical “work” performed is the same in both cases (moving a amount of mass up a certain height).
In you’re example of a motorbike, it’s a no-brainer. But since the weight of the bike is quite small in relation to the rider, and the duration is quite short (less then 1min from the video above) the ergonomics of it all come into play. I think the only real way to know is just test in which position it’s easiest for the rider to run the fastest.
Skills in carrying a bike also come into play. It’s not that easy to run fast with a bike object on your shoulder. And without clattering into other people and bikes.
(You can use that to your advantage too, as its also hard to run around someone carrying their bike awkwardly.)
Carrying often seems the better choice, until you get there and inexplicitly start pushing anyway.
I pushed, and came over the top tied with three other guys, but someone was 10 yards ahead of all of us.
I watched the start of the 50 mile run, which has the same start, and it was similar, some puck of man just straight sprinted up that hill. Won by 20 yards. It was super impressive.
I was there this year and that hill is so much steeper than it looks in the YouTube videos. Altitude sickness took me out at Printer Boy aid station, but it was a beautiful course.
I’ve never seen the start of that race in person, but I’m pretty sure I’d be done for the day if I tried to run up that hill anywhere near the front of the pack. Chapeau.
