High-intensity intervals  are great for boosting metabolism and burning more calories, but if you want to get the caloric benefit without all that effort, here are a few simple things you can tweak during your workout.
- Work out with a buddy: Have a friend who's just as eager to get in shape as you?Working out with a buddy will help you push yourself to hit your goals, and then some. Just be sure to pick a motivated friend who won't convince you to go shopping instead of sticking to your workout plans.
- Go in the morning: Even if you're not a morning person, getting your workout over with in the morning can help you get more out of it. Long days, lots of errands, or just feeling famished after work can cut into your workout enthusiasm in the evenings. So get up and get going if you want to see results.
- Get your carb fix: If you're feeling famished and low-energy and haven't eaten in a while, a high-carb snack right before your workout can give you the energy you need to power through and perform better than exercising while starving. Go for a piece of fruit or a handful of crackers if you need energy, stat. And don't forget to drink water before your workout as well, since dehydration can also lead to fatigue.
- Wear a heart rate monitor: If you're serious about knowing your calorie burn, investing in a heart rate monitor is a great idea. Wearing one during your workouts will help you learn more about just how your efforts are paying off, when you are in your optimal calorie-burning zone, and which workouts give you the most bang for your buck.
- Set a reward: Telling yourself you can get that almond croissant if you hit your morning workout may be counterproductive, but motivation is key to staying in the zone and seeing yourself to the end. Instead, tell yourself you can watch a favorite program after your run, for example, so you want to finish faster. Set small rewards  for things like moving up a weight size or exercising for five more minutes, and pat yourself on the back for a workout well done.