If you want to boost your stamina, you don’t necessarily have to run a marathon or spend all day in the gym. Short bouts of really intense exercise (a.k.a. high intensity interval training or HIIT) can actually improve your endurance when done in combination with traditional training.So if you can’t bear to spend another minute on the dreadmill treadmill, try this quick HIIT workout instead.

This routine is short (just 25 minutes), but the unpredictable format keeps your muscles guessing to build strength and agility. For each round, you’ll continue to up the intensity, but don’t worry: You get a chill, active recovery between each exercise. Add weights for an extra challenge or simply start with your own body weight.

To recap, dumbbells are optional depending on your fitness level.Start with a 2-minute dynamic warm-up, followed by a 20-minute workout (see below), and a 2-minute cool-down.

3 Rounds of 6 Exercises (45 seconds on, 15 seconds off):

  • Squat With Overhead Press and Chop
  • Lateral Lunge with Plank
  • Reverse Fly
  • Sumo Squat With Curl and Chop
  • Walkout With Sprawl
  • Diagonal and Lateral Hop

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