It's literally been years since I last posted here, but this is a question I want to take to this forum, simply because of the sheer number of active forumites!
A detailed background story to begin with...
I started cycling nine years ago, at age 25. For the first couple of years I did little more than ride around just for the sake of it. I joined a local bike club (where I'm still an active member eight years later) and went along on their recreational rides on weekday evenings and sundays. Slow rides. A lot of chatting, not a lot of panting...
I gradually improved over the years, but I was never very fast.
Then in 2009, after I had a minor heart condition surgically taken care of (a very benign AVNRT), I not only started working out harder, I also got my first power meter. That really kickstarted my training. I'm a numbers guy, and I need cold, hard numbers to motivate me. Training by feel gets me nowhere - I just ease off prematurely. Training with power allows me to track my progress, and that really helps.
Back in 2009, I got myself tested at a local sports testing clinic and got a VO2max of ~59, at 153 lbs, and an FTP of ~240 W (lactate test). 15 months later, with a lot more training at higher intensity than previous years, I re-tested and got ~68 at 143 lbs and an FTP estimated at around 260 W (lactate test). A fair bit of improvement, not just because of the weight loss. That's around 0.3 L/min higher in absolute terms.
From there on I've seen a steady but moderate progression. I tested at ~68 VO2max (ramp test with gas analysis mask) at a higher weight (155 lbs) early this year, or in absolute numbers about 4.7 L/min. Estimated FTP of 270 W.
I have a Monark 828E ergometer bicycle for my indoor training (and during the "winter" half of the year, I mount my Power2max power meter on it), and I also use it to do my own ramp tests occasionally, to keep track of my fitness level.
Now, up until now, I've never been very structured and dedicated in my training. Sure, I've put a decent number of hours in there, but not much compared to the truly dedicated cyclists I know. I'm at around 275 hours of bike-related training so far this year. Roughly 4200 miles (I only count distance outside), so not a lot. I completed my first season as a competitive cyclist this year. We don't have categories in Sweden, but rather two different kinds of classes. There's Elite, Senior and Sport ("beginner" essentially). Aside from that, we have age groups. M30 (30-39), M40 (40-49), M50 (50-59), M60 (60-64), and so on. The first kind is age-independent, as long as you're 18 (or is it 19?) or over. You need an Elite licence to be able to race in the Elite class, and a Master licence for Senior, Sport and the age-group classes. I raced mostly in the M30 class.
Half the races in M30 are time trials. 12-19 miles long. And even though I'm not that strong in TTs, it's still my greatest love in cycling! I have a few podium finishes, but they're sadly mostly due to a lack of competition. My main nemesis proved impossible to beat this year. Not surprising since his average power is about 25-30 W higher than mine, and he's not much bigger (taller, but thinner). My 2014 season will be almost exclusively time trials. There's not many of them. Perhaps only about 10-12 real races.
Earlier this year, during a playful team time trial on regular road bikes, I averaged 284 W over 40 minutes, and it felt fairly easy. We were supposed to stop where we stopped so that's why we stopped (and not because I was tired), but I could easily have gone on for more than the full hour. So I would guess that, at that time, I could have averaged close to 290 W for a full hour, in a real race. I lose about 7-8 % in my TT position, though, but I think it's partly due to a lack of time on the TT bike. My best TT effort was 277 W for just over 40 minutes, but I'm not good at pushing myself hard on the TT bike. That's another thing I need to work on for next year.
Which brings me to the real question. How far should it be possible to push my FTP, given dedicated and FTP-specific training at a greater volume than previously? I doubt very much that I'm at my peak, considering how relatively little and unstructured I have been training. Is 300 W for a full hour a realistic goal for early April next year? How about 310 W? Even higher? That's probably about 25-30 W up from my current level, or 10-20 W up from this season's peak in July.
How strongly does VO2max limit FTP? I mean, looking at some of the top female pros, with VO2max probably in the low-to-mid 70s at 115-130 lbs, their absolute VO2 is far lower than mine, yet some can push 300 W or more for an hour.
Sorry, this is a lot of text, but I want you to have the full picture. Verbose is my middle name.
Bottom line: is getting to 300+ W possible in five months? What would it take?