This won't require significant time or a gym membership; typically 10 to maybe 15 minutes is all that's required to get in a great workout that will go a long way toward stabilizing your running form.
A Need for Treadmill Speed
Even if the weather outside is awful, and your next A race isn't for months, you can't simply neglect speed work if your winter goal is to improve your fitness. This is especially true for runners who frequent the marathon or half marathon distances, as the better part of your season is spent running at a generally "endurance" oriented pace. Not changing your program in the winter could result in fitness stagnation, not to mention mental burnout. Besides, you might earn an extra gear that could come in handy at the end of your next big race.
Speed work on the treadmill is the perfect antidote for the winter running blues, as you can dress as if it's spring and run at some really fast paces to recruit some new muscles. I suggest you limit your speed sessions to just once per week; you don't need much more to challenge your body, especially if you are following the hill guidance as written above. Here's a sample session you can do:
- Warm up for 10 minutes, building from very easy to about marathon pace. Be sure to set the treadmill to 1.5 percent here.
- Do three repeats of 30 seconds each (3 x 30) all at 5K pace. To take a break, simply hold onto the handrails and jump your feet to the outside panels. When ready, hold the handles and jump right back in.
- Do two to three, one-mile repeats at your current 10K or 5K pace. Rest as long as is needed between the intervals by jogging at a very casual pace.
- Cool down with a mile of jogging and walking, then take a moment to stretch out your trouble areas.