Classic periodization theory suggests that winter is the time of year for cyclists to spend long hours on the bike working the "aerobic base." Long endurance or zone 2 rides are encouraged as a means of establishing a strong aerobic foundation upon which to build cycling success for the year ahead. But if you live in colder climates where snow covered roads are the norm, that means a lot of long, boring trainer rides.
One cycling and triathlon coach we know turns classic periodization on its head. Instead of prescribing long endurance rides on the trainer, this coach prescribes regular FTP (functional threshold power) workouts to his athletes during the winter months. What is the rationale behind such an approach designed to improve cycling performance?
First, the coach recognizes that trainer workouts can be boring. FTP workouts keep things both interesting and challenging for the athlete. A typical FTP workout includes 30 minutes of warm-up with some 30-60 second pick ups in the last 3rd of the warm-up. Then the athlete is instructed to ride for a 6-10 minute interval at a prescribed wattage level that is at or near functional threshold (or lactate threshold) power. The FTP interval is repeated once or twice on a recovery equal to half the length of the interval, followed by a 10-15 minute cool down. This is challenging workout completed in a relatively short period of time (75-90 minutes).
Second, the coach prescribes four bike workouts per week with 3 of the 4 of those workouts featuring FTP intervals. While the workouts are short, lasting no more than 90 minutes per session, each workout yields 70-80 training stress score (TSS) points bringing the weekly total to 280-300 TSS. That forms a CTL (chronic training load) base of 38-42 TSS.
Third, the "base" that is being formed is on a foundation that consists of difficult workouts that stress the cardiovascular system more acutely than long endurance rides do. Workouts featuring FTP intervals are similar to progressive strength training workouts where the muscles are being asked to lift a heavier and heavier load each week. Once the load is reduced and the athlete recovers during an unload week, the athlete's ability to lift more weight - or push more power in this instance - is the direct result of the training block.
Once the spring comes, and the cyclist can ride outside, there is still plenty of time to do long endurance rides. But now, the aspiring cyclist who has spent the winter months working FTP will be at a higher level of fitness than if trainer time had been spent doing endurance work.
Bottom line: FTP intervals yield more bang (training stress) for the buck (time spent).