When running it’s tempting to start at your top speed. This is especially true when racing—why not bank some extra time in the beginning, in case you slow down later in the race? However, starting out too fast, especially in longer distances, will inevitably cause you to slow down as you burn out your muscles and energy stores too early. The best thing to do for both day-to-day running and races is to start slow and get faster as you go.
This is called a negative split, where the first half of your run or race is slower than the second half. It may seem counter-intuitive, but starting out slower allows your body to warm up and by the second half of your run you can go at faster speeds with seemingly the same or less effort. Almost all world records, including the most recent marathon world record, were broken using the negative split technique. The difference could be only a matter of seconds between the first half of a race and the second, or it could be several minutes; either way, negative splits guarantee you will finish feeling strong and will likely give you a PR. For marathoners, running a negative split can be the secret to avoiding the dreaded wall around mile 20.
How do you run a negative split race? You want to practice control and careful pacing during the first few minutes of the race. With all the adrenaline that effervesces at the starting line of a race, it is too easy to begin at an all-out pace. If you’re not careful, you may even start significantly faster at goal pace, which means you will have a harder time maintaining pace later in the race. Starting off too fast is the least effective way to race. Instead, start out a 5–15 seconds slower than your goal pace, and then ease into your goal pace as your muscles are warmed up and the crowds from the starting line dissipate. If you’re feeling strong—which will be likely since you did not start out too fast – push the pace a bit in the final miles of the race.
In addition to using negative splits in racing, you can using negative splits in your daily runs. Negative split training runs are also commonly called progression runs, because you get progressively faster as you go. The real beauty of progressions runs is that they can be adapted to any type of run: easy runs, long runs, and tempo runs. Progression runs can be ran according to the clock, by feel, or by pace.
For easy to moderate runs, you can run a negative split by simply picking up your speed in the second half of your run. For example, run easy for 2 miles and then try to run another 2 miles in a bit less time than it took you to run the first two. If you are running on an out-and-back route, try to finish the “back” portion faster than you ran the “out” portion. You don’t want to go all out when you pick up the pace. If you are running by pace, try to go 15-30 seconds per mile faster. To prepare yourself for racing, go a bit slower than your usual pace for the first half mile or so.
Progression runs can also add variety and an extra training stimulus to your long runs. In the last quarter of your long run, pick up the pace a bit and accelerate towards your goal pace. This may be hard, since your legs are feeling tired, but you may find that the change in pace helps you out mentally. So if you’re training for a half marathon, run the last three miles of your 12-miler at your goal half marathon pace; for a full marathon, run the last four miles of a 16 or 18 mile run at your goal marathon pace.
Progression runs offer a way to change up your tempo runs while still receiving the same physiological benefits. After warming up for a mile or two, run a bit slower – about ten to twenty seconds – than your normal tempo pace. Over the course of the next few miles, work your way up to tempo pace. In the last mile, push yourself to run faster than tempo pace. This type of run not only teaches you to run fast on tired legs, but it also teaches your mind to push through discomfort in running.
Progression runs are my favorite way to spice up a treadmill run. You can adapt them to how long you want to run and it makes the miles go by faster. My favorite treadmill progression run starts out easy and finishes just faster than half-marathon pace (or a comfortably hard pace for those of you who don’t race). Adjust the speeds according to your goals and current fitness. I made this workout 45 minutes long, but you can lengthen it or shorten it as best fits your training and your fitness!
Here’s my favorite treadmill progression run:
These articles offer great further reading on negative splits: