HIIT

Seven minutes for a workout — who doesn't have time for that? That's why we've been loving this quick circuit workout from the American College of Sports Medicine, which burns major calories in a short amount of time. Keeping the intensity up — and the rest periods short — is key, so make sure you are pushing yourself during each 30-second spurt! You'll need a mat and a chair or bench. Repeat the circuit up to three times.

Learn how to do all the moves here, and get the printable poster of this seven-minute HIIT workout here.

Sometimes, all you need is 10 minutes to feel healthier, less stressed, and more fit, all while burning a surprising amount of calories. The following total-body workouts range from five to 10 minutes and will work up a sweat while still keeping your busy schedule in mind.

1. Do-it-anywhere workout: You can do this 10-minute, no-equipment workout anywhere where you have space for your mat; set up your laptop and follow along to our workout video here.
2. Wake-up workout: This short and sweet five-minute workout will help you energize in the morning to get ready for your day.
3. Max HIIT workout: Very high-intensity interval training is the way to go to save time and burn major calories — it's even been proven in studies. This seven-minute HIIT workout is the perfect circuit to raise your heart rate while working your entire body.
4. Yoga with weights workout: Follow along to our 10-minute hybrid yoga workout for a creative way to strength train: with a stretching yoga sequence that incorporates dumbbells.
5. Yoga flow workout: For a more traditional, relaxing yoga sequence, try this 10-minute yoga flow workout video.

Five more intense, short workouts after the break!

It's well known that too much inactivity can slow down metabolism and lead to health problems, but it can be hard to fit in a long workout if you're just starting an exercise routine. Because research has shown that just a few minutes of activity can both improve your health and increase your calorie burn, make a goal to get a least 10 minutes of exercise a day.

One recent study found that just 2.5 minutes of intense activity can help you burn an extra 200 calories throughout the day. Another found that just four to six 30-second cardio sprints in between short periods of low-intensity exercise can help lower the risk of heart disease and diabetes. The key is to make sure that you are challenging your body with high-intensity interval training (HIIT). It can be as simple as running up and down the stairs, doing 30-second intervals of jumping jacks during an evening walk, or trying one of our Tabata workouts: an eight-minute squat and push-up workout, a 10-minute mat workout, or this 10-minute calorie-blasting Tabata workout. With all the benefits of just a few minutes of exercise, there's no excuse not to work up a sweat!

Interval training will help you reach your running goals, and this rocking playlist will keep you feeling motivated. Not only has alternating between intervals of pushing your body to the max and slower periods been proven to help you lose belly fat, but also, interval training also revs up your metabolism! Ready to bring some heat to your run tonight? Keep reading for the list of songs and their accompanying treadmill speeds and inclines, plus the Spotify playlist.

No matter what your favorite way of getting your cardio in, if you're trying to burn calories fast, you should be familiar with HIIT. HIIT stands for high-intensity interval training, and the concept is simple: do your cardio at a normal pace, but pepper your routine with short intervals — usually 30 seconds to a minute — where you are pushing yourself to the max.

Incorporating HIIT into your normal routine is a smart way to work out; not only are you increasing your endurance and becoming better at your workout, but you are also burning more calories in a shorter amount of time. High-intensity workouts also target belly fat to help you sculpt those six-pack abs. But while high intensity intervals are effective, make sure you space out your HIIT workouts so you aren't pushing your body too much. Alternate with lower intensity cardio workouts, along with your normal strength-training routine, for an exercise plan that's safe and effective.

Here's how to try HIIT:

• A short elliptical interval workout
• A 45-minute pyramid treadmill workout
• A 30-minute indoor cycling interval workout

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If you find it hard to lose weight with your busy schedule, the news keeps getting better. First, just 20 minutes of exercise was proven to help increase your metabolism. Now, a recent study has found that working out intensely for just 2.5 minutes can spur calorie burn throughout the day — an extra 200 calories' worth.

In the latest study, five healthy men performed sprint interval training on a stationary bicycle (five 30-second intense intervals with four minutes of easy cycling in between). Although the men were sedentary the rest of the day, they ended up burning 200 more calories during the days they did the short bout of exercise than the days they didn't exercise at all.

Even though this was a small study, the encouraging results are reason enough to add intense intervals into your workout routine. It's also good news for those of you who can never seem to fit a full workout into your day. Read on for ideas on intense exercises you can do anywhere for 2.5 minutes so you too can reap the afterburn benefits.

Is all the hype about high-intensity training worth the effort? FitSugar reader (and certified trainer) JessicaSmithTV interviewed an expert to get the truth behind whether or not this type of training is one-size-fits-all. She shared her findings in our 10 Pounds DOWN! community group.

By now, chances are you’ve heard of high intensity interval training (aka HIIT) and Tabata. You may even be incorporating this type of maximum effort training into your regular cardio routine. But is it the best type of training for you? If so, how often should you be doing it?

The long and short answer? It depends on what your goals are, says Jeffrey A. Dolgan, MS, CSCS, an exercise physiologist at Canyon Ranch Hotel & Spa in Miami Beach, Florida. "The bottom line is that there is no one answer as to which combination of duration and intensity is best for everyone." Dolgan says it’s important to remember that the length and intensity of your intervals has a huge impact on which energy system (anaerobic or aerobic) your body uses.

Find out what type of training you should be doing after the break!