What's the Point?

Several folks have asked me: "What's the purpose of your winter training plan? I know it's important to ride lots in the winter, but what exactly are you trying to accomplish?" It's a simple question, but it got me thinking about exactly what I want the plan to do to my body, so here's my best shot at explaining it:

In reading this, it might be helpful to reference the 2008 Winter Training Plan and Coggan's energy systems table.

Winter training goals, sort of prioritized:

1. Increase L4 - FTP (functional threshold power). During the racing season, and particularly towards the end of the racing season, I usually find myself either recovering, riding 1 to 2 hour hard group rides, or doing short, intense races lasting from 30 minutes to 2 hours. Recovery is a requisite, and there are many benefits to hard group rides and races, but neither is great for increasing FTP. By late season my aerobic engine needs maintenance. By the end of my off-month (October) this year, my FTP had fallen by about 20 watts to 260 watts from my season peak of about 280, which occurred in July or August. Nine base weeks of mostly L2/L3/L4 work including at least one long (3.5-4.0hr+) group ride will rebuild my FTP. Since November 1st, I've measured a steady FTP increase of 2.25 watts per week. If I can keep up that rate of increase, I'll be back to last year's peak of 280 watts by the end of the nine-week winter base training period. I'll start the year with last year's peak number - a larger base on which to build the season.
2. Build Chronic Training Load. My CTL had dropped to about 70 TSS (total stress score) at the end of October. I want my CTL to be at least 100 when the racing season starts, and I probably should build it to around 110 if possible before the 5-day, 8-stage Tour of Atlanta in May. One of the best ways to increse CTL is by doing 4.5-hour Peach Peloton rides every Saturday that routinely deliver between 250 and 350 TSS points. TSS=(NP/FTP)^2 x 100 x hours. A good rule of thumb to make steady year-to-year progress: raise CTL each November to the level of the prior April.
3. Regain/maintain endurance ability (L2/L3). The absence of frequent long rides during the season might diminish my ability to ride comfortably at L2 or L3 pace for 4 to 6 hours. The long Saturday rides in my winter plan reestablish and strengthen whatever biological systems enable me to do that. To be honest, I'm not sure exactly how those endurance systems differ from the ones involved in 45min FTP workouts, but I'm sure there are differences. (Probably fat burning ability vs glycogen burning ability?). Being able to ride comfortably at L3 for 5 hours isn't critical for a cat4 bike racer who's races rarely exceed 40-50 miles in length. But the BBQ Bass Ride and the Six Gap Century are more than 50 miles long and I'd like for them to be fun.
4. Maintain/develop L7 - neuromuscular (NM) sprinting ability. I'm no sprinter. But I've recently learned that a little sprint training goes a long way. I've increased my sprint from about 950w max to 1160w max in 10 weeks with only eight 15sec sprint intervals per week. I think most of that increased power comes from establishing muscle memory and NM adaptations. If you've ever started lifting weights from scratch, you know how much progress you can make in the first month or two - an awful lot. Most of that initial increase comes from teaching your brain and nervous system how to lift the weight - not from larger or stronger muscles. Your nervous system has an automatic governor to prevent you from injuring yourself (you've read about crisis situations in which people display almost superhuman strength - their brains have temporarily turned the governor off). As you do sprint intervals, your NM system slowly raises the level at which the governor will kick in (the adrenaline rush at races does the same thing). That lets you put out more wattage with the same legs. Doing one L7 workout per week during the base period maintains those adaptations so you don't have to learn them again in April. It also does a tiny bit to maintain your ability to tolerate lactic acid.
5. Maintain ligament and tendon strength. Very simple - sprint workouts keep your ligaments and tendon's strong through the winter so they're ready for the more intense work in spring. I think this makes injuries less likely.
6. Maintain VO2max and anaerobic systems (L5/L6). The November and December 4-hour Peach Peloton rides on Saturdays often have 20-minute attack zones. The AZs are a good way to keep the anaerobic engine from atrophying over the winter. Too much L5/L6 work in November/December and you won't have the legs or time to develop the aerobic side properly; but I think a little each week will make it easier to kick-start the VO2max (build) and anaerobic workouts in January and February.
7. January L5 -VO2max. This is transition territory. The 5-minute interval workouts at 110% FTP in January continue to build your aerobic system, but also begin to strengthen your lactate tolerance as speed skills gradually revisited. See training level 5 in Coggan's table. L5 is not that much different that L4, but lactic acid tolerance is initiated.
8. February L6 - Anaerobic. There is a dramatic difference in the way your body is powered when putting out L6 power compared to when it's putting out power in the L1-L5 zones (see Coggan table above). That's why you can't stay powered at L6 for very long. The 1-minute interval workouts in February develop your L6 (anaerobic/lactic acid buffering) system and prepare you for the intense race efforts required during the season.