In the week before a half marathon, you should run about 40 to 60 percent less than your normal training volume. If your typical week is 30 miles, that means roughly 12 to 18 miles total, spread across shorter, easier runs. This reduction, called a taper, lets your body absorb weeks of training and arrive at the start line fresh rather than fatigued.
How Much to Cut Your Mileage
A large meta-analysis of tapering studies found that reducing training volume by 41 to 60 percent produced the most significant performance improvements. That’s the sweet spot: enough of a cut that your muscles repair and energy stores refill, but not so drastic that you lose fitness or feel sluggish on race day.
For a half marathon specifically, Mayo Clinic Health System recommends a 50 percent reduction during race week, with a smaller 30 percent cut the week before that. So the taper actually starts about two weeks out, with race week being the bigger drop. If you’ve been running 35 miles per week at peak training, race week would look like roughly 15 to 18 miles total.
Some runners worry this feels like too little. It’s not. The fitness gains from your training are already locked in. What you’re doing now is letting your body convert that training into performance. Cutting volume more aggressively (75 to 85 percent) has also been studied in 7-day tapers, but those reductions are more common for shorter races or elite athletes with very specific protocols.
Keep the Intensity, Drop the Distance
The most important rule of race week is this: reduce how far you run, not how fast. The research is clear that maintaining training intensity while cutting volume is what makes a taper work. If you drop both, you risk feeling flat and heavy on race day.
In practice, this means your runs are shorter but should still include a few pickups at your goal half marathon pace. A typical approach is to include two or three short intervals at race pace during a midweek run, something like 4 to 6 repetitions of 1 to 2 minutes at your target pace with easy jogging between them. The total workout is much shorter than your normal sessions, but the pace keeps your legs tuned to the effort you’ll need on race morning.
Easy runs should stay easy. The goal is to keep your legs turning over without accumulating any new fatigue.
What a Sample Race Week Looks Like
For a runner who normally logs 30 miles per week with a Sunday race, a practical schedule might look like this:
- Monday: Rest or very easy 2-mile jog
- Tuesday: 4 miles with a few race-pace pickups
- Wednesday: 3 miles easy
- Thursday: 3 miles with 2 to 3 short race-pace intervals
- Friday: Rest
- Saturday: 2-mile shakeout run
- Sunday: Race day
That totals about 12 to 14 miles before the race itself, roughly a 50 to 55 percent reduction. Adjust the numbers proportionally based on your own peak mileage, but keep the pattern: short runs, a couple of quality sessions, and rest days bookending the race.
The Day-Before Shakeout Run
A shakeout run the day before your half marathon is a short, easy jog designed to loosen your legs and calm pre-race nerves. Think 1.5 to 3 miles at your slowest long-run pace, around a 3 out of 10 effort. You should be able to hold a full conversation without any heavy breathing.
If running the day before feels like too much, walking for up to 30 minutes or cycling at low intensity for about 10 minutes works just as well. The point is gentle movement, not a workout. Some runners prefer to do their shakeout two days before the race instead, which is equally fine.
What to Do About Strength Training
If you’ve been doing strength work alongside your running, your final session should fall 2 to 4 days before the race. That last session should skip heavy eccentric movements (the lowering phase of lifts), high-impact plyometrics, and anything that leaves you sore. Focus on lighter weights with the lifting portion of each movement, and keep the session short.
If you’re already feeling beaten up from training, skip the strength session entirely. A light movement session or some dynamic stretching is a fine substitute. Race week is not the time to test your limits in the gym.
Fueling and Hydration During Race Week
Because you’re running less but eating normally (or slightly more), your muscles will naturally top off their glycogen stores, the carbohydrate fuel they burn during endurance exercise. In the 36 to 48 hours before the race, aim for about 10 to 12 grams of carbohydrates per kilogram of body weight per day. For a 150-pound runner (68 kg), that works out to roughly 680 to 816 grams of carbohydrates daily, which is a lot of pasta, rice, bread, and potatoes. You don’t need to stuff yourself at one meal. Spread it across the day.
For hydration on race morning, sports nutrition guidelines recommend drinking 5 to 7 milliliters per kilogram of body weight at least 4 hours before the start. For that same 150-pound runner, that’s about 12 to 16 ounces of fluid. During the race itself, aim for 400 to 800 milliliters (roughly 13 to 27 ounces) per hour depending on your sweat rate and the weather.
Dealing With Taper Anxiety
Almost every runner experiences some version of the “taper tantrums” during race week. You’ll feel restless, convinced you’re losing fitness, and suddenly notice aches and pains you never had during training. A mysterious knee twinge, a foot that feels off, a calf that seems tighter than usual.
These phantom symptoms are extremely common and almost always harmless. They happen because you’re scanning your body for problems. Sports psychologist Justin Gross compares it to scanning your body for an itch: the moment you go looking, you’ll find one, and then you can’t stop thinking about it. Most of these sensations pop up one day and disappear the next.
When you catch yourself spiraling, try a simple sequence: notice the worry, distance yourself from it with a phrase like “there’s the worry story,” and redirect your attention back to whatever you’re doing in the present moment. The discomfort of backing off your training is real, but it’s a sign the taper is working. You’re storing energy, not losing it. Race day is where you spend it.