Yeah, 2 bottles of water ain’t near enough.
As I was reading the OP, I assumed “riding a century” was riding a horse for 100 miles. I wonder how hard that would be.
Body type can also matter. I’ve done many centuries, even this one in under 5 hours when I was in my prime, but I was really struggling to trudge through a half-marathon I had trained well for. With an Eastern-European mesomorph body type, cycling will always be more congenial for me than running.
I’ve never needed more than even a bottle of water before. Even running I never needed more than 20 or so ounces of water.
Parenchyma I once took the bike/run times from a local 1/2 iron and plotted each participant’s bike time vs. their run time. It was relatively linear so it gave me some idea of what kind of bike pace I should be able to ride given my run pace. My bike time is way below where others seem to be. I’ve never been a strong cyclist. I’ve done something to my leg so I can’t run, which is why I’m now trying to focus on cycling. Maybe this will help me improve, but it looks to me like I’m just never going to be even a moderately good cyclist.
If you haven’t tried it already, riding with a club, even a recreational club, can really inspire and motivate you. The summer I was my fastest, I had a lot of free time and rode with the local recreational club three times a week. We might have had one Cat 2 rider in the fast pack. Instead of staying with the medium riders, I started out killing myself just to not get dropped by the fast pack. Soon I could hang on for most of the ride, and at the end of the season even take the occasional short pull at the front. It was a friendly group so they were okay with my being a wheel-sucker. I’ve never ridden so consistently fast since, mostly because I can’t ride as much and can’t make the club ride times. Oh, and that aging thing.
100 miles/ 16.7 mph = 5.9 hours
A decent marathon is over in 3.5 hours. You have no real experience in hydrating and feeding yourself for a century ride. As a runner turned bike rider, I suffered through similar problems with comprehending the difference in the challenge.
If you are pushing hard, it is extremely difficult to digest anything solid after 4-5 hours. The people who do serious long distance cycling use liquid food products similar to those offered by this company:
If you really thought you could ride 100 miles on 20 oz of water, that’s just not very realistic. I can ride 50 miles and hardly touch my bottle, but anything much over that distance changes things radically.
You may or may not have the innate ability to compete in distance bike events. Your experience so far isn’t really telling you much other than you don’t know what you’re doing. You’ll see what I mean if you stick with it.
Finally, if you find that road riding just doesn’t do if for you, try trail riding. On singletrack. I wish I’d taken up it years before.
Walt
One simple word, friends – COAST. You can coast for a very long way on a bicycle. And you can maintain a speed considerably faster than jogging speed with much less effort.
I personally have ridden two centuries, and I routinely did 50-70 mile rides, at a time when I couldn’t jog ONE mile.
I didn’t mean to imply I thought I could ride 100 miles on 20 oz of water. I brought somewhere around 50 oz of water, but that was still about 6x what I needed on a 50 mile ride.
I fully realize I don’t really know what I’m doing on a bike. Just like with my running, it will take time to figure out what works for me. For example, in running I found out eating during a run was really bad for me. Others swear by eating sugary/carbo loaded stuff.
I do quite a bit of trail riding. There is an amazing trail system near me and I love heading out into it. I would do more, but I haven’t found a group to ride with and I’d prefer not to go alone.
Boyo Jim I’m not sure how far you can coast on a bike. I hear what you are saying, but I honestly had nothing left at the end of those 95 miles. I was nearly passing out in my seat.
Parenchyma I went with a local bike club once last year. Unfortunately it wasn’t a good fit for me. They ride even slower than I ride and half way through they stopped for an hour lunch on a 50 mile ride. There are other clubs but I haven’t checked them out yet. If my leg doesn’t heal up soon I will definitely be looking into it, though.
You can coast for nearly as much time as you pedal. You can essentially rest while still making forward progress. IMO it is not remotely comparable to the effort needed to jog.
The gear does make a HUGE difference, though. I can ride a light road bike with thin tires two or three times farther than I can ride a mountain bike with fat knobby tires.
No, it was about 6X what you could get away with on a 50 mile ride. You probably “needed” more and the longer the ride, the fewer corners you can cut.
The reference that I have closest at hand recommends ~12-20oz of liquid and 400 calories/hour for long rides. I know what I can get away with (less than that) and I know that if I try to get away with a lot less than that over a long ride, I’ll bonk.
She does have a trainer. But he is not local. He mostly just keeps her training on schedule. I also bought her a compu-trainer for her bike. With our weather, it’s very hard to get miles in.
She also rides with a friend that is trying for her first IronMan.
She is not fast, and making the cut offs are always a concern.
She is currently training for the Phoenix IronMan in November.
Would you do this when working up to a marathon? A couple of 13.1s and then a 20 miler and then the full 26.2? Probably not. Work up to the century by adding 10 or 15 miles a week and it will be no problem. These will help you refine your nutritional plan to know what works for you on the bike, which may be very different than what works for you running.
As far as the original topic of a 100 miler being harder than 26.2, I agree with most of the others and say no way. In the run up to my last Ironman, I rode 100+ miles 6 times while I never ran 26.2 miles until race day and only went 20+ three or four times. That is very typical for most long distance triathletes.
You really need to find a closer foodmart. 
J/K - Congrats on the effort.
Actually that’s exactly how many marathoners train.
My brother has signed up for that one as well. Strangely enough, he is in CO as well.
I’m really hoping to try one in the next year or two. Running used to be the easy part, but no more, so I’m not sure how it will go, if at all.
Whether she if fast or not, just finishing an ironman is an incredible feat. Almost beyond my ability to comprehend, really.
Greenhorn My hat is off to you for completing an ironman. I think 100 miles in a bike should be easier than a 26.2 run, but at least for me for now it isn’t. I’m just a fluke that way. As I’ve said, my biking is very poor, especially compared to my run. If I were training for an ironman I’d probably be willing to spend the effort in working my way up to a 100 mile ride as then I’d probably have a better base and finish stronger. Right now on my rides I’m trying to concentrate on getting faster, so my rides are usually shorter (20 to 25 miles) and I’m trying to see how long I can hold 20mph and raise my overall average mph.
Indeed, your post reminded me of a fluff piece I saw awhile ago about a training bicyclist who biked 100 miles a day, and I never until now compared it to (not) running 25 miles a day, every day, to train for a marathon. I think it’s safe to say that unless we find people who run 25 miles a day 5 days a week, that biking 100 miles is easier.
Well, not really. They will do 15, 16, 18, and a 20, or something similar.
http://www.halhigdon.com/marathon/Mar00novice.htm
Intermediate and Advanced runners are likely to do multiple 20’s during training.
If you are thinking about taking up triathlons, a good resource is www.beginnertriathlete.com. It has articles, a very active and friendly forum for asking questions and an excellent online training log for tracking your workouts.
Finishing an ironman is not really that hard. The hard part is finding the time to train properly for it. Race day is easy if you pace yourself and fuel properly. I’ve done one stand alone marathon and that hurt more than either of the two ironmans I’ve done. If you are worried about not being able to run as hard or often as you used to, don’t be, hardly anyone actually runs the marathon. It is more a fast jog or a shuffle or a walk.
There are ironman training plans all over the place if you search for them so, although many people do it, in my opinion, hiring a coach is not necessary. I used a plan from a book called Be Iron Fit for the two that I have done and it was good enough to get me in the top 5% of my age group last year.
Oh and my hat is off to you for qualifying for Boston. That is my goal for this year and will be making my attempt at the Philadelphia marathon this fall. I was eleven seconds short of Boston qualifying at my first attempt, but hopefully I’ll make it this time and race Boston next year.
Those are probably the ones walking the last 10k.
Another thing to consider is that many/most average runners can walk/run a marathon without too much problem. Mix in walking at times and don’t worry about time and a lot of people can go 26 miles, just like if you take lots of rests and eat/hydrate properly most people can finish a century. The marathon may take 10 hours, but that’s just an average of 2.6 MPH, but that’s probably similar to riding a century in 10-12 hours.
I forgot to address this. You can’t compare race times to riding on your own. In a race, the intersections are closed and people hand you bottles of gatorade and water while you are riding by at almost full speed. Even though it is against the rules, many people cheat and draft other riders, which improves speed considerably (although there are ways to get the benefit of drafts while staying within the rules). For me, the difference between a training ride of 56 miles and a half iron race could be 3 or 4 miles an hour.