Burn a pound of fat with these diet and exercise tips. Credit: Corey Jenkins / Getty Images

You've probably heard this tidbit of knowledge a million times: A pound of fat is 3,500 calories, so to lose a pound you need to burn 3,500 calories. It's not a perfect rule, but if you're looking to drop a little weight, it's a good place to start. Here, six strategies will burn a pound of fat in a matter of days. Some don't even require breaking a sweat.

Drink Green Tea
The catechins — a type of antioxidant — in green tea have been shown to help fat oxidation and aid in weight loss. One study from the Journal of The American College of Nutrition found that four cups of green tea a day, or the equivalent amount of green tea extract, could result in a weight loss of more than a pound per week. The study was done on obese subjects, but other studies have shown similar numbers. As a basic guideline, drinking 20 to 24 cups of tea (spread out over a week and without cream or sugar) could result in one pound of weight loss. Days to Burn One Pound

Fire Up Brown Fat
Brown fat helps regulate body temperature when you get cold by burning calories. Thankfully, research shows that you only need to get a little chilly — in the range of 62 to 64 degrees Fahrenheit — to activate your brown fat. Dr. George L. King, chief scientific officer at Joslin Diabetes Center in Boston, an affiliate of Harvard Medical School, says that while this is a relatively easy way to up your overall calorie burn, it's not going to get you in beach-body shape overnight. "Brown fat can burn an additional 100 to 300 calories a day," he says, adding that losing a pound from brown fat alone would likely take anywhere from two to four weeks. Days to Burn One Pound:  14 to 28 

Cap Carbs
"It is calories in, calories out, but the type of energy you're burning is important," says Joe Anderson, PhD, a professor of bioengineering at the University of Washington. "Your body wants to burn sugar," he says. It's only after your glycogen stores have been depleted that you'll tap into your fat reserves.

Currently Anderson is working on creating a device that will measure the level of acetone in a person's breath — a gauge for whether you're burning fat. "Acetone is a byproduct of fat burning,” he says. "The more fat you're burning, the more acetone you're producing." According to Anderson, on a typical diet your breath contains one part per million acetone. On a low-carb diet (less than 130 grams a day), you can increase the amount of acetone to two parts per million, which will translate to burning a pound of fat every two weeks. Days to Burn One Pound14  

Gain a Pound of Muscle
"Research shows that one pound of muscle equals 50 calories burned per day," says Ryan Sonnenburg, Senior Training Department Head, Life Time Athletic, Green Valley, in Henderson, Nevada. "Therefore, 50 calories a day for 365 days a year would burn 18,250 calories." That equates to losing 5.2 poundof body fat annually. A pound of muscle mass takes at least one to two weeks to build, and to add it, you should lift weights at least three times a week with compound exercises (like squats and pull-ups) in multiple sets of 10 to 12 reps. Add that extra pound of muscle, and with the 50-calorie-a-day rule, you’ll cut a pound of fat in 70 days. Days to Burn One Pound70 

Perform Complex Strength Moves
While an additional pound of muscle erases a pound of fat in 70 days, the good news is that if you use multijoint movements to make that gain, you'll burn more calories as you build muscle. Todd Gates, a New York–based strength and conditioning coach, says that your total energy expenditure goes way up when you load up the weights and use multiple muscle groups at once. "A back squat, for example, you're using your back, core, quads, glutes, hamstrings," he says, adding that these are all big muscles that require a lot of oxygen. Spend about an hour doing squats, lunges, and deadlifts, and you'll burn between 300 to 500 calories. That means it will take between 7 to 10 sessions to burn one pound of fatDays to Burn One Pound7 to 10

Combine HIIT With Resistance Training
High-intensity interval training (HIIT) is a gold mine for burning calories, and that makes it great for weight loss. You are working anaerobically, which means most of your energy is coming from glycogen, not fat. However, Sonnenburg says combining HIIT intervals with resistance work creates a great fat-burning workout because it cues the body to produce human grown hormone and testosterone. A study in the Journal of Sports Science found that HIIT intervals could increase HGH production by 450 percent. How much a HIIT-plus-resistance workout will increase your own HGH or testosterone levels depends on a lot of factors. However, Gates says a typical 30-minute HIIT strength session can easily burn 300 to 500 calories, so bank on doing 7 to 10 sessions to burn a pound of fat. Days to Burn One Pound: 7 to 10  

If All Else Fails
The 3,500-calorie rule doesn't work for everyone. "From a math standpoint, it’s correct. But it's not necessarily always true," says Caroline Cederquist, MD, who practices in Naples, Florida, and specializes in weight loss. Cederquist says that things like metabolism dysfunction and insulin resistance can both inhibit fat burning. And how much fat you have affects the mix of glycogen and fat your body burns when you workout, says Vancouver, Canada–based personal trainer Joshua Duvauchelle. If you’re confident you're doing 3,500 extra calories of work without seeing any weight-loss results, see your physician.