Please choose the correct ending to complete the given sentence: Health: [header] How to determine your fat burning zone [title] Calculate your fat-burning zone with a formula. [step] There's a relatively simple formula to help you determine where your fat-burning zone falls. It's not 100% accurate, but will give you a relatively reliable range to aim for.

Ending1: [substeps] Use the formula to make sure your fat-burning zone falls somewhere in your body, not to take that range into account when determining how many calories to lose. A healthy fat-burning zone is between 65 and 70 calories. Ending2: [substeps] The formula is x = a + b + b + f. [title] Find out how many calories you burn per day. Ending3: [substeps] First, find your maximum heart rate (mhr). To do this, subtract your age from 220 if you're male; subtract your age from 226 if you're female. Ending4: [substeps] Your fat-burning zone will consist of your calorie count (calories), activity level (activity intensity), and overall body calorie consumption. Most dieters report that they are burn-reducing fats when they lose half of their calories in the previous year.

Answer format: ending1/ending2/ending3/ending4