Many runners don’t know how to train during the winter. They know that they should train, but they lack a clear sense of the purpose of winter workouts. And if you don’t know why you’re running, it’s difficult to determine how to run.
Assuming you wish to be in good racing shape for one or more spring events, then your winter training has not one but three distinct objectives: developing general fitness, increasing durability, and improving body composition. Let’s take a look at each of these objectives.
Developing General Fitness
When you’re training for a specific event, you want to develop a type of fitness that is specific to that event. Although a 100 km mountain race and a 5000-meter track race both qualify as distance-running events, each demands a specific type of fitness that is very different from what the other requires. During the winter, however, when your next race is many weeks away, you want to be pretty good at everything rather than great at one thing. Therefore your training should be balanced, featuring a mix of easy runs, long runs, and faster runs at every intensity from marathon pace to full sprints, as well as a little hill work to boost your stride power.
While some runs should be harder than others, none of the runs you do during this period should be more than moderately challenging. For example, a good peak workout to do before a 10K race is 6 x 1 mile at 10K race pace with 1-minute passive recoveries between efforts. A more appropriate workout targeting the same intensity during the winter would be 6 x 1 km at 10K pace.
In order to get in peak shape for a race or series of races, you have to take some risks in your training. More precisely, you must train close enough to your limits that there’s a chance you might get injured or (less likely) become overtrained. One of the major objectives of winter training is to reduce the likelihood that you get injured or burn out later by increasing your body’s durability.
The most effective way to do this is to gradually increase your running volume until it reaches a level that is at or near the highest level that is indefinitely sustainable for you. If you plan to peak at 50 miles per week right before your next race, for example, build gradually up to around 40 miles per week during the winter.
What most runners fail to recognize is that, whereas running injuries are caused by running a lot (obviously), running a lot is also the best way to prevent running injuries. That’s because running increases the body’s ability to withstand the stress of running. Think of it this way: Who is more likely to get injured trying to run 50 miles in one week—a runner who routinely runs 40 miles a week or a runner who has never run more than 20 miles in one week? The answer is plain. The key to increasing durability through winter running is to find a mileage sweet spot that is relatively high for you but at the same time well within your body’s limits.
You can also increase your injury resistance through strength training and mobility work. You should do these things throughout the year, of course, but the winter is a good time to prioritize them because doing so will make your body more balanced before you start really piling on the miles. It is beyond the scope of this short article to offer detailed guidelines on strength and mobility training, but there are many good existing sources available. One that I recommend is Jay Dicharry’s book Running Rewired.
Improving Body Composition
You can’t race your best without being lean. Where body composition is concerned, form follows function, so you will tend to get leaner automatically as you train for peak performance. But the best time to prioritize shedding excess body fat is during the off-season, before you begin a race-focused training cycle. The reason is that when you are taking on training workloads that are close to your limit, you need to make sure you are eating enough to maximize performance and recovery. Attempting to sustain the sort of daily calorie deficit that is needed to shed body fat relatively quickly could pull the rug out from under your training. But during the winter, when your workloads are lower and you’re not concerned about maximizing performance, intentionally eating 300-500 fewer calories per day than your body uses will stimulate fat loss without negative consequences other than a little hunger.
Strength training also promotes a leaner body composition by increasing resting metabolism. The best types of exercises to use for this purpose are compound movements involving large muscle groups and performed with heavy loads. Examples are deadlifts and back squats. These are not the best exercises to do during race-focused training, when you’ll want to focus on movements that increase stability, but during the winter these bread-and-butter heavy lifts should come to the fore.