I've had the same experience with my legs and cycling. I usually cycle pretty regularly from spring to mid autumn. But I rarely do during winter. It's just not enjoyable for me when it's -10°C.
Every year during the winter, my legs basically turn into sticks. This year especially since I broke a bone a few months ago. For the first few weeks of spring my stamina and leg strength is at most a third of what it was the previous year. But once I've regularly cycled again for a handful of weeks, the strength returns incredibly quickly.
Every year during the winter, my legs basically turn into sticks. This year especially since I broke a bone a few months ago. For the first few weeks of spring my stamina and leg strength is at most a third of what it was the previous year. But once I've regularly cycled again for a handful of weeks, the strength returns incredibly quickly.