Working out at work
Take a few minutes during your lunch break and try some of these high-intensity exercises. Getty Images

We’ve all used the excuse, “I don’t have time.” But when it comes to exercise, you always have time. You just have to find the right workout. The standard guidelines on aerobic exercise recommend 150 minutes per week of moderate-intensity exercise, which can be unrealistic for adults juggling personal, family and professional priorities. Instead, scientists and fitness experts recommend high-intensity circuit or interval training using your body weight for resistance.

Just minutes of intense exercise per week can keep you as fit as someone who runs for hours, Canadian researchers reported in an issue of the Journal of Applied Physiology. Chris Jordan, the director of exercise physiology at the Human Performance Institute in Orlando, Florida, told the New York Times “there’s very good evidence” that a few minutes of high-intensity training provides “many of the fitness benefits of prolonged endurance training but in much less time.”

The best part? No equipment necessary and you’re done in less than 10 minutes. So take a few minutes during your lunch break, in between classes or when the kids are napping to break a sweat with one of these time-saving workouts.

If you have seven minutes, complete these 12 exercises using only your body weight, a chair and a wall. The workout, published in an issue of the American College of Sports Medicine’s Health & Fitness Journal, combines the benefits of a long run with a trip to the weight room.

If you have six minutes, and feel like a flashback to MTV’s Laguna Beach, try Lo Bosworth’s six-minute “fat blasting” workout to tone abs, glutes and arms. Using only your body weight, perform each exercise for 60 seconds, then repeat the circuit two more times.

If you have five minutes, do the following nine exercises for 30 seconds each. This particular high-intensity workout published on Active.com requires no equipment and is an excellent strength-training component for runners and endurance athletes.

  • WALKING LUNGES Works: Calves, glutes and hamstrings. How to do it: Stand tall with your hands on your hips, and step forward with your right foot. Lower your entire body downwards, balancing most of your weight on your right side. Once your right knee is at a 90-degree angle, directly over your ankle and not your toes, you can use that leg to lift your body back up. Repeat the same sequence on the left side and continue lunging forward 15 times per side.
  • JUMPING JACKS Works: Total body. How to do it: With your feet together and arms at your sides, jump into the air, bringing your arms up over your head and your legs outward. Jump back to center and repeat.
  • PUSH-UPS Works: Pectorals, deltoids and triceps. How to do it: Begin doing push-ups on your feet, but transition to your knees if you aren't able to complete all reps.
  • LATERAL LEG LIFTS Works: Adductors, glutes and hip flexors. How to do it: Lie on one side with your legs stacked on top of one another. Slowly lift the top leg into the air and lower back down. Repeat on the other side.
  • CRUNCHES Works: Abdominals and lower back. How to do it: With your back and feet flat on the ground, lift your back up a few inches off the ground, stopping short of doing a full sit-up. Use your core to lift and lower in a continuous motion.
  • BURPEES Works: Total body. How to do it: As you are standing, bend over and put your hands on the ground, hopping your feet back into push-up position. Quickly hop your feet back to your hands, stand up straight, reaching your hands towards the ceiling, and repeat in rapid succession.
  • PLANK Works: Core. How to do it: Get into push-up position, but rest your upper body on your elbows, rather than your hands. Be sure your back is straight and your hips aren't sinking into the ground. Hold the position for 30 seconds.
  • DIPS Works: Triceps. How to do it: With your back facing a stable bench or chair, put your hands shoulder-width apart on the edges, with your feet out in front of your body. Rest your weight on your heels as you lower your body down with your arms. Once you have dipped several inches down, use your arms to raise your body back up.
  • STEP-UPS Works: Glutes and hips. How to do it: Stand with your feet hip-width apart in front of a platform 6 to 12 inches off the ground. Bend your right knee and place that foot on the platform as you lift your body with that leg, bringing the left foot up on the platform. Slowly step back down, controlling the movement with the left leg. Repeat on the other side.