If you are a beginning bike racer, or are considering getting into racing, you’ve almost certainly heard or read about interval training. However in this same case, you’ve almost certainly seen the overwhelming about of information out there about what kinds of intervals to do. Perhaps you’ve read everyone going on about the precise heart rate zones to be in, or riding at a percentage of their FTP, or even people claiming that to do intervals properly you need a power meter. For the beginning/aspiring racer this is all rubbish. Certainly those things will help you ride your intervals more efficiently, however for newer riders they’re totally unnecessary.
Intervals are simply riding hard for a (relatively) short period of time, then resting, then riding hard again. The number of times you repeat this, the length of each work/rest portion, and the power you use in each portion are what create different types of intervals. It should be clear that there is an infinite number of ways to create and “interval.” Thus the question is, what intervals should you be doing? There are entire books and PhD theses written on this subject, but for the beginning racer it is really quite simple.
If you want to train your “go fast” (anaerobic) engine, I can’t recommend highly enough doing 1 minute intervals. They’re incredibly simple to do without any electronic assistance, they “feel” like racing, and they will make you faster. The article that made me decide to start doing intervals was from My World From a Bicycle, a now retired blog with some excellent bike racing information. His fantastic description was “Ride absolutely as hard as you can for one minute, then soft pedal as easy as you can for three minutes; repeat 5-8 times or until you think you see Jesus.” I’ll add one addendum to that, which is that after 8 times you may feel like you could keep going. A key to doing intervals properly is that you want to keep relatively even power output throughout all intervals. Thus the question to ask yourself as the intervals get up there is, can I still go hard? Picture yourself in a race. If there was a big surge at the start, would what you have now be enough to keep you in that race? If not, it’s probably time to call it a day. This is not something to be ashamed of! Remember, you don’t get stronger by riding, you get stronger by riding and then resting.
If you want to train your “go far” (aerobic) engine, consider doing 2×20, by which I mean 20 minutes all out, 5-10 minutes rest (you want your heart rate to settle and your breathing to slow a bit), then 20 minutes again. If you’ve been riding 25-50 mile rides at a “hard” pace and measuring your progress by your average speed, you may feel like only doing 40 minutes of work is silly. However study after study have shown that these types of intervals are significantly more effective than steady-state riding at increasing your aerobic engine. If you do them correctly you will be gassed.
Now this brings us to a difficult point, which is doing 2×20’s correctly. The difficulty is in gauging your effort so that you don’t go too hard at the start, or finish up and realize you’ve gone too easy. I really like to start out doing 2×20’s on a trainer. This allows you an extremely precise measurement of your effort using just a normal bike computer and watching your speed. A good description of a 20 minute interval is the following: For the first 2 minutes it should feel easy, at 5 minutes you should start to feel it, around 7 minutes you should be thinking “how the hell am I going to keep this up for another 13 minutes?!”, and then the last 13 minutes are giving it everything you’ve got to keep that pace. Try it once or twice, and adjust accordingly.
If you own a heart rate monitor then you get a double benefit from 20 minute intervals, in that they’re a decent functional threshold heart rate (FTHR) test. Joe Friel suggests doing a 30 minute interval, and measuring your average heart rate for the last 20 minutes of it, and setting this to be your FTHR. You can also just get in a decent warmup, then do a 20 minute interval. Some sites suggest subtracting 5% from your average HR during a 20 minute interval to get your FTHR. With this number in hand, it will be easier to follow other intervals you find around the interwebs. They may suggest going at a percentage of your FTHR (or FTP). Since I don’t own a power meter, when I see FTP I tend to just mentally substitute FTHR, which will get you close enough.
How often should I do intervals?
A good rule of thumb is, at most twice a week. Intervals tax your body pretty hard, and the point of doing intervals is to push your body to the max. So if you’re still tired for doing too much, you can’t stress your body enough, since your muscles will be too tired to get your heart rate up. So spread them out a bit and make them quality.
When should I do these intervals?
Again, a good rule of thumb is to do aerobic work in the early part of the season, before races have begun. Once races are just getting started (or just before) start mixing in some anaerobic work. Then when you’re in the swing of the season you want mostly anaerobic intervals, but you still need to do some aerobic work so that you don’t lose that “go far” engine.