Cold, short days move many workouts indoors and I often head to the pool for a cardio workout. Intervals are not just for running; they are great to add into your swim workouts too. There are some kickboard sprints to focus on toning the legs.
Here's a workout for you to try:
100 yrds Freestyle - easy
50 yrds kick Freestyle
50 yrds kick Backstroke
50 yrds kick Breaststroke
100 yrds pull* Freestyle
The Main Event:
200 yrds Freestyle
8 x 25 yrds alternating Freestyle, Backstroke, Breaststroke and Butterfly***
200 yards Freestyle
4 x 25 yrds Freestyle kickboard sprint
4 x 25 yrds Breaststroke
50 pull Freestyle
100 Freestyle - easy
* Pull: Hold a buoy with your legs and use only your arms to swim
** Rest the listed amount between reps/laps
***If you don't swim Butterfly, substitute Freestyle
This workout is 1350 yards, or about .82 miles (a swimmer's mile is 1500 meters, or roughly 1650 yards - 66 lengths in a 25 yard pool).
Fit's Tips: If you are new to swimming check out this beginner's program to get you from sitting on the side of the pool to swimming a mile.