Road Cycling - Training for First Century (but not from scratch)

I'm hoping for some advice on training for a century. I've been cycling for a little over a year, and have gotten up to the point where I regularly do 100-120 miles a week, and have done a few weekend rides of ~50 miles recently. I'm preparing to do my first century in mid-September, and want to make sure I'm really ready. The problem is that most 4-week/6-week training programs I've seen appear to assume that you're starting from a pretty low level of fitness. They start off pretty slow, with low weekly mileage and weekend rides of only 10-20 miles, before ramping up gradually. But I'm not interested in dialing back from my current mileage. So what are some good tips to prepare for a first century when I'm already at a pretty good fitness level, but just want to close that last 50 miles? Thanks!

Add to your existing riding one ride a week that is 60 miles, then the following week do 65 miles that one day a week, then the next week do 70, then the next week do 75 miles... you get the idea.

Michael

Sounds like you are already at the 3 weeks before the ride point. So just jump in there.

For example, this Training for a Century (http://bicycling.about.com/od/trainingandfitness/a/century.htm) page; you are at week 7 already:
Week/long ride/week's mileage
1 25 55
2 30 65
3 35 73
4 40 81
5 45 90
6 50 99
7 57 110
8 65 122
9 50 75
10 Century Ride Yeah!

The usual idea is to add 10% distance a week to the longest ride.

You have time to do some more fast interval rides to boost your average speed, too.

Add to your existing riding one ride a week that is 60 miles, then the following week do 65 miles that one day a week, then the next week do 70, then the next week do 75 miles... you get the idea.

Michael

+1

Which basically follows the 10% guideline ... increasing the long ride by 10% each week.

What I found is that if you're doing that sort of weekly mileage, and doing 50 milers on the weekend, you're probably set for the century.
If you can do 50 miles and feel like you owned it, you can go and do 100. Just lay back, stop at the feed/water stops for at least 10 minutes, and enjoy the day. Perhaps hold back about 1.5 mph average slower than a 50 mile ride.

You will likely slog through the last 30, and they may be a bit tedious and unrewarding, but not a real problem physically.

If you can own a 75 mile ride, well then its all good. But the summary is don't necessarily worry about having ridden close to 100 miles before the big ride.