How to Run a Faster Half Marathon
The half marathon is one of the most popular road race distances in the United States. According to the Running USA annual report, nearly 2 MILLION people finished a 13.1 mile race in 2015!
13.1 miles makes for a unique event in that it takes significant endurance to cover the distance, but does not require the time needed to train for a full marathon.
Training to run a faster half marathon changes how workouts are approached. For a half, threshold and long runs take on greater importance. The long, slow run provides a way to increase aerobic strength, which is vital for endurance races, and the threshold run adapts the body to clear lactic acid more efficiently. Runners seeking to improve their half marathon time should consider training with these workouts as a primary focus.
How to Run a Faster Half Marathon
All training plans designed to help you run a faster half marathon start with general workouts that build to meet the demands specific of your goal. For the half marathon, base training provides a foundation of endurance by adding more miles to your weekly long runs and total volume of miles. For runners who stick to low mileage or who have not yet ventured into the world of half marathons, long runs are of the utmost importance to establish the minimum level of endurance to cover the 13.1 miles. Workouts such as fartleks, hill repeats, and strides help build strength and prepare you for speed work like 400m and 800m repeats as appropriate.
As the plan progresses, you will see a narrowing of the elements of each workout. Distance, pace, and time at goal pace will focus on creating a stress on the body that closely mimics what you will experience on race day. A good training plan will build in such a way that allows you to step from one workout to the next without feeling overwhelmed or too fatigued – workouts will be challenging, but not impossible.
Half Marathon Specific Workouts
In the last six to eight weeks of training for a half marathon, your focus should be on spending more time at goal race pace. This means time running close to your lactate threshold. To improve the lactate threshold, consume a steady and varied diet of tempo runs.
If you recall, the lactate threshold is the point when lactic acid begins to accumulate in the bloodstream faster than it can be cleared. Running at or just under this threshold will train the body to clear lactate acid from the bloodstream more efficiently and improve your speed endurance.
Speed endurance differs from speed development in that development utilizes VO2 Max workouts (running at your top gear) to gain strength and speed. Speed endurance improves the ability to sustain a pace for longer periods of time. Coach Jeff Gaudette at Runner’s Connect gives a good example in his article comparing different half marathon training plans:
What is the average pace you need to run to break your [half marathon] PR? Now, what is the fastest pace you can run a mile? As you can see, you easily have enough speed to break your [half marathon] PR. What you can’t do is hold that speed for 13.1 miles.
For runners new to the half marathon, start by building your longest run to 10-12 miles six weeks before your race. This allows you to increase the distance and add progressions to longer runs.
A “progression run” is when you aim to increase your pace throughout your run. This could be in the form of running a few seconds faster per mile with each passing mile or running the last two miles of a long run at goal half marathon to 10k pace. Doing this will simulate running hard at the end of a race when your legs and mind are tired. The peak long run for new runners should be 13-15 miles. More experienced runners may go beyond 15 miles depending on experience and goals.
There are several different varieties of tempo runs. For the purposes of half marathon training, focus should be on tempo intervals and alternating tempo paces.
Tempo intervals are exactly what they sound like: tempo runs broken up into intervals. This means you will run a given time or distance at your tempo pace, jog for a short recovery period, then hit your tempo pace again. This looks something like:
3 x 2 miles at half marathon pace, 4 minutes recovery
Breaking up a tempo run into intervals enables you to spend more time at your goal pace which means more time training your body to efficiently deal with lactic acid.
Alternating tempo runs aim to closely simulate a race scenario. In this type of run, there is no clear recovery period like in the tempo interval workout. Instead, alternate your pace to be slightly faster than marathon pace and slightly slower than 10k pace (10 to 15 seconds faster per mile on both sides).
For example, if your half marathon goal is 90 minutes, a workout might look something like:
7 miles – 7:00, 6:45, 7:00, 6:45, 7:00, 6:45, 7:00
Rarely in a race will you find yourself running the same pace the whole time. You may have to accelerate around another runner or get swept away by cheering crowds. This type of run aims to simulate the ups and downs in pace you will inevitably experience, and train your body to cope with fluctuations in lactic acid. Due to the demanding nature of these workouts, beginners should avoid them, saving them as a tool for later training cycles.
Sample Half Marathon Progression
The following sample progressions are adapted from the book Run Faster by Brad Hudson. A fantastic book that clearly explains the principles of training and how to progress workouts for distances from the 5k to the marathon.
As we have seen before, the above workouts build upon each other. Each workout progresses either the distance run or time spent at a given pace, eventually increasing to goal pace. This build up will help prevent injury and give you confidence in your ability to hold your goal pace for the entirety of your race.
Remember, these are meant to be examples of how to properly progress your workouts from week-to-week. There is no single “best way” to run a faster half marathon that works for everyone!
When considering a training plan, don’t immediately look at the last few weeks of workouts; this can be discouraging and foster thoughts of “How could I ever complete those workouts?” Instead, make sure the workouts in the first few weeks seem achievable, then look to each successive week to make sure each week builds on the last. If you work with a coach, you can avoid being overwhelmed by not looking beyond any two week period.
With these tools, you will be ready to run a faster half marathon in no time. Good luck!