In the time it takes you to fold your laundry, you can get a full-body workout in. When the holiday season comes around, training windows get a lot tighter. If you're stuck at home with family and friends coming to you, or are on this road several days, incorporate this 15-minute bodyweight routine, courtesy of Spartan pro Cali Schweikhart, into your week.

After a quick warm-up, Schweikhart, who is also a certified strength coach, has you perform five exercises that tax multiple muscles at once. She also has you do them for time, not reps, which is a great strategy because it allows you to scale the difficulty to fit your fitness level.

Another thing to keep in mind is that you will want to use an interval timer for this workout. This may seem like a small detail, but an interval timer lets you set your work and rest time for a certain number of rounds. That way, you won't have to futz with your phone mid-workout to reset your timer, which can ruin your flow. Instead, you'll just listen for the first beep to start working, and then the second beep to stop.

40 Seconds On, 20 Seconds Off

This 40-second-on, 20-second-off model is a great setup for any workout, not just the one provided below. Feel free to sub in your own exercises and play around with the time on and off, as well as the total rounds. Fifteens may not be enough for some of you Spartans. (Though trust us when we tell you this won't be easy.)

The Warm-Up

Lunges (3 x 30 seconds)

Side-to-side lunges (3 x 30 seconds)

Jog in place (3 x 30 seconds)

The Workout

Complete three rounds of each movement, resting only 20 seconds after each exercise.

Burpees (40 seconds on/20 seconds off)

Squats (40 seconds on/20 seconds off)

T push-ups (40 seconds on/20 seconds off)

Froggers (40 seconds on/20 seconds off)

High knees (40 seconds on/20 seconds off)