Dancing is fun. I like cross country skiing and snowshoeing. Walks outside and winter hikes are fun if you dress for the cold. Everything is quieter and more still than in the summer.
I also do shoveling of my neighbors’ driveways and walks sometimes. They are old ladies, and when I have time and energy I will volunteer my time to snow removal for them. There are countless opportunities to volunteer your time for this kind of activity, but be sure that you are not going to hurt yourself first.
I love my gym membership (at Anytime Fitness). The treadmills each have their own TV on them so I can flip stations, and they have a cool bike/game that allows me to race, ride through different terrains on the screen, or chase dragons and run them over on the screen. The coolest part is that in all of those activities, the resistance of the bike mimics the terrain, so that when I see myself going uphill the pedaling becomes harder. It makes the workout go a lot faster.
Since you mention soft in the middle, you might want to try yoga or Pilates. These require very little or no equipment (rubber bands go a long way and they fit in a suitcase). These are fabulous strength-building and body-sculpting routines, and you can register for group classes to start your workout for a lot less than a personal trainer or gym membership. The equipment is often small enough that you can take it with you on a plane and stay on your routine even when traveling for business or taking a vacation.
How about swimming? There are places other than expensive gyms to go swimming in the winter (such as the YWCA), and it is a fantastic workout. I never really liked swimming myself, but I have a friend who does swimming and kung fu, and it sure keeps him fit.
My sister loves basketball and broomball in the winter. Her exercise is more social than mine, which I envy sometimes. There are leagues for all ages and fitness levels if this interests you.
You can also try community education programs — I took a badminton class for a few dollars a class and got a serious workout. That game can get as intense as tennis! Community education classes like that are usually really cheap but a great way to get access to a school gym or some other space for a few hours to play around and get sweaty.
There are tons of ways! Pick whatever sounds fun to you!