Among all the commonly run race distances, marathon training is completely unique. Unlike other events like the 10K, or even the half marathon, training for the marathon necessitates a specific focus on physiological adaptations that aren't of great importance to shorter races.
In the marathon, there are three goals of training:- Develop your aerobic threshold, or the fastest pace you can run while staying aerobic
- Improve fuel efficiency, or how efficient you can be at burning fat instead of carbohydrates while running at goal marathon pace
- Increase muscular endurance, or how long you can run without your legs falling apart
As such, it's critical that you understand these physiological components to ensure you're training optimally for the marathon.
More: The 3-Month Marathon Training Plan
Train Your Aerobic Threshold
Aerobic threshold is defined as the fastest pace you can run while using the aerobic system as the primary energy pathway. As we'll cover in more depth in the next section, once you begin to rely more heavily on anaerobic energy pathways as your energy source, you burn through glycogen faster, and produce more lactate than your body can efficiently process.
Your marathon pace, and thus your finishing time, is directly correlated with your aerobic threshold.
The majority of your marathon workouts should be focused on improving your aerobic threshold. The more you develop your threshold with targeted workouts, the faster it improves (i.e. you're able to run faster while staying within your aerobic threshold).
More: How Much High-Intensity Training Do Runners Really Need?
The key to improving any specific physiological system is frequent, repeated bouts of stress. To target the aerobic threshold, your training plan needs a steady diet of workouts right around your current, not goal, marathon pace. By remaining in the 10- to 15-second window of your current marathon pace, you're able to target your aerobic threshold.
Training your aerobic threshold is mentally challenging because the workouts are not extremely taxing. You can easily run faster and push the pace, but if you run too fast or too hard—the most common marathon training mistake since every runner likes going faster—you miss the target and make the workout less effective.