Note that Derek Clayton ran a faster marathon than Don Kardong, despite having a significantly lower VO2 Max. If the cardiovascular system adaptations were the most important determinant of how fast you go, VO2 max would tell the whole story?but it doesn't. The biggest VO2 max does not always win.
If Running Is Muscular, How Do We Think Muscles?
If running a 20-minute 5K is a set unit of work, or fitness, then being able to do that same course in less time (i.e. do more work) means you are now fitter. To run faster we need stronger muscles or more of them. When we get this granular, then it's easy to see how every training session is nothing more than an opportunity to recruit more motor units.The more you activate a motor unit, the more it begins to take on slow-twitch characteristics. In fact, it has been shown in laboratory mice that chronic electrical stimulation will convert the plantaris muscle from 90 percent fast-twitch to 90 percent slow-twitch. As you increase the intensity of the average training session, you recruit all of the slow-twitch fibers and begin to recruit fast-twitch. Each flavor of muscle cell becomes better and better at what they do. The slow-twitch fibers become really good at being slow-twitch fibers. Fast-twitch fibers begin to take on the characteristics of slow-twitch fibers: they can go longer and burn fat for fuel. The net result is that your capacity for work will increase: slow-twitch fibers become better and stronger at what they do, and they increase in number.
In order to make this work, however, you need to do a significant amount of moderate or high intensity work so as to recruit intermediate and fast-twitch fibers, causing a shift in their characteristics towards slow-twitch. These muscles will, in turn, produce less lactate and improve their fatigue resistance, driving up your lactate threshold and sustainable pace. In other words, all this work will make you into a faster runner.
How Does This Change Your Training?
The popularity of less-is-more programs has grown in the last few years. While not all of them are good, most are way better than the traditional long-slow-distance approach that just counted on you accumulating miles at a set (low) aerobic effort. This volume-oriented approach does work, but it requires so much volume that either the average John/Jane Doe (A) doesn't have time for it or (B) won't be able to physically survive the miles. Her are a few suggestions to revamp your plan to make the most of the training you are doing.- Benchmark Your Fitness?Schedule a 5K time trial run on a local, flat course. Do your best and use the resultant time and pace per mile to shape the rest of your training. Even if you don't get that granular with the data, regular testing every 4 to 6 weeks will give a good indication if your fitness is improving!
- Weekly Intensity?Don't be afraid of intensity, especially in smaller doses. The standard Marathon Nation Training Week has both Tempo and Interval training sessions. A great example is 4 to 6 repeats of 3 minutes each at 5K pace, with 2 minutes of recovery. By the end of your workout you'll have almost racked up a 5K of solid work without too much fatigue.
- Smart Long Runs?Make those long slow runs a thing of your past by cutting the volume by 2/3 and adding intensity to the run. A 15 mile long slow run can quickly become a 10 to 12 mile effort as 4 miles easy, 6 miles at marathon pace, 2 miles at half marathon pace (or as fast as you are able). By the time you are done, you'll have done more "work" than the standard easy run and you'll be done faster! Save those uber long runs for a race simulation or for your final training peak.
- Improved Recovery?More more work means more rest, period. Don't fall victim to thinking your new fast-self is immune?running harder is actually harder on our bodies. From self massage to weekly stretching to two days off a week to post-run ice baths and recovery shakes, how you absorb the work is just as (if not more!) important than the work itself.