Running on Snow and Ice
Your favorite loop is now covered in snow, so you run on a treadmill. The next day the temps stay the same and thus the snow does not go anywhere. You are resigned to the treadmill again and soon enough after a few days you find your motivation is lacking. You start to reconsider, is it ok to run on snow? Here are some quick tips for running on the various winter surface conditions.
fresh snow everywhere
If it is less than an inch, slow easy running even in regular shoes can be just fine, depending on the tread of your shoe. Your steps will be a bit shorter and the pace slower, but you will still get that aerobic adaptation in. Just be mindful that when running around corners your stride will likely slip slightly through push-off, so best to seek out a route that is mostly long straight-aways.
If it is more than an inch the running mechanics can become more of a running drill, which can be helpful in developing other parts of your stride (like knee lift), but given the new firing-pattern this type of running should only be done in short bouts (likely at least half of the duration you would normally run).
packed snow everywhere
If the snow has been walked, biked, or drove on and is now a packed, hard, crunchy snow this too can be a great surface to run on, even in your regular shoes. In fact, many runners in northern areas run regularly in these conditions and find this type of surface to be great for recovery, given the soft surface. If you feel you are not sinking with each step, you might even be able to get in some tempo or progressive runs.
snow and ice everywhere
Now it is time to break out your ice cleat running spikes (good RW guide here: www.runnersworld.com/gear/g42815867/ice-cleats-for-shoes), though you can certainly wear these in all snow conditions. Note, if you run on ice with ice cleats you are very likely running more on your toes, which can strain your calves if you do too much too soon, so for this reason it is often best to save any up-tempo work for the snow. Regardless, be sure your calves are loose and flexibility before wearing ice cleats, and stop every 10 minutes or so for the first one or two runs to 'check-in' and stretch the lower legs.
snow - but only in some areas
Ice cleats are not recommended in these cases, as running on clear pavement can quickly strain your feet, calves or shins. Instead, wear your regular running shoes and simple be ready to change your stride along the way - slightly shorter steps on snow, back to normal longer steps on the pavement. In fact, a recent study showed that elite runners can more easily and more quickly fluctuate their stride length and stride rate, so these conditions can be a great place to practice! (pmc.ncbi.nlm.nih.gov/articles/PMC7607923)
snow and ice - but only in some areas
Likely just not worth running outside here. You should not wear ice cleats, given some areas are clear and a hard surface with spikes is not recommended, and the back and forth of the conditions is just too new of a situation, and thus easy to be too much on your body. Time to hit the treadmill, where you can work on strength by, for example, running your normal easy run on a consistent 3% incline (something you cannot do outside).
Benefits to running outside in the winter?
Running outside requires different biomechanics to running on the treadmill, and the benefits of breathing dense cold air in regards to strengthening your lungs can help increase your fitness to new levels. For these two key reasons try braving the winter conditions from time to time, just be ready to adjust your footwear, adjust your stride, and adjust your pace expectations.