Monarch Park (Coxwell south of Danforth) has a new year-round track.
The track is the longest indoor track in Toronto. The track is 370.67 meters long and it is marked (and measured) for the following distances (60m, 100m, 150m, 200m, 400m, 600m, 800m, 1,000m, 1,500m, 1 mile, 2,000m, 3,000m, 5,000m, 10,000m).
It's covered by a dome in the winter. It's $8 for a day pass (including showers and change rooms), $55/month, or $255 for a season's pass.
There's also a pool (in the school attached) and spin bikes for triathlon training.