5 Hour Century

I'd say it depends on how much of a sacrifice you can put on all other aspects of your life. Basically, I think if you have the time to devote to riding, and train smart, then absolutely, you can do it. I have two predictions: 1. On the day you do it, you will weigh less than 190 pounds. 2. On the day you do it, you will be a proud kid again.

groskilly said:

I am 56 years old, 5'10", 190lbs. I began cycling on a regular basis 2 years ago with a goal of staying in good shape. Over this past year I participated in several Centuries with the resulting desire to reduce my overall time.
My current goal is to ride a Century under 6 hours. Naturally this has alot do do with the amount of climbing and generally the ones I am riding have 3500 to 4500 of ascent.
My question to the group is: Is it a reasonable goal to ride a Century in 5 hours at my age ?

I haven't managed to break the 5 hour century yet : and that's with 11k+ miles in my legs this year.

I have come close - 5hrs 10 and 5hrs 8 but under 5 hours, no.

I am 39.

I can't offer an opinion to say if it is feasible at your age/weight/fitness :
all I know is that it is bloody hard maintaining 20 mph or more over what are rolling courses that I cover.

agreed. terrain is a big factor in the average speed equation of riding a fast century.

i did a 4:56 over mostly flat to gently rolling terrain weith 18 miles of easy hills on the route (tosrv, central/southern ohio).

that same year i did a 4:28 over pancake-flat ground (hancock horizontal hundred, western ohio). the largest 'hill' on that course is a freeway overpass! there are spots on the topograhic map where the 1' elevation changes are over a mile apart.

where i live, it's darn difficult to maintain any kind of 'bragging average' because of the hills.

here's some encouragement: a fellow that rides with us retired at age 62. at that age he could hold 20 mph all day long and then some...solo, not in a pace line. he had NO sprint, NO acceleration, could not interval and was only a fair climber. regardless, it was all some of the young pups could do to hold his wheel on the flats.

You can clearly achieve your objective of a 5 hr century, but how you do it and how much additional training it will require depends on what you are trying to do. If you simply want a 5 hr time, then the easiest way is to ride with a large group on a relatively flat course in light winds. It doesn't really take much sustainable power to ride at 20+mph in a large paceline, given that you are riding at 30-40% less power than the guy on front. I rode the Cool Breeze Century in California this past summer and could have easily ridden it in <5 hrs if I had hooked on with any one of the relatively large club pacelines that were buzzing along at ~25mph. In fact, lots of smaller groups (e.g., 3-6) ride at 20+mph as well. If, on the other hand, you want to ride 100 miles solo at 20mph, you will need to bring your functional threshold to at least 250w, maybe more. This is because of the decrease in sustainable power as a function of duration. In my case, I estimate ~5% decrease in sustainable power per hour. And, you will definitely need ~200w to maintain a 20mph average speed, even on a relatively flat course with light wind. If the course is hilly or windy, the required power will increase exponentially.

Good points on riding solo vs a large pack. Am curious on your power esimates though. When you say ~200W to maintain 20 mph solo, does that assume the rider is down in the drops, with a fairly decent aero position?

Have never ridden a flat century, but it seems to me that even in the best of conditions, staying down and maintaining 20 mph for 5 hours solo would take some serious training.

dhk said:

Good points on riding solo vs a large pack. Am curious on your power esimates though. When you say ~200W to maintain 20 mph solo, does that assume the rider is down in the drops, with a fairly decent aero position?

Have never ridden a flat century, but it seems to me that even in the best of conditions, staying down and maintaining 20 mph for 5 hours solo would take some serious training.

No, I'm not assuming a very aero position or aero bars. I'm assuming riding on the hoods. The problem with projecting ride times for a century is that there is no such thing as a flat course with no wind (assuming you rule out velodromes). Even very slightly rolling terrain or winds above ~5mph result in significantly slower speeds (because you always lose much more uphill/upwind than you gain downhill/downwind). According to the model at analyticcycling.com, it takes only ~170w to do 20mph on a flat course for a 190 lb rider with a 0.6 frontal area. But, I've found the power numbers to be a little on the low side for flat courses. So, I think ~200w is more realistic even for a "flattish" course with light winds. Now, 200w doesn't sound like much until you look at the power/duration curve and realize that 200w for 5 hours means you can do 250-275w for 1 hour (at least my power curve looks like that). Personally, if what I wanted was 5-hr bragging rights, I'd find myself a fast group and hook on the back.