Getting healthy by perfecting the "calories in calories out" technique

According to a 2020 Ipsos survey, 45 percent of the world's population is striving to lose weight. They choose to accomplish it by increasing their physical activity and improving their diet rather than by dieting. That's effectively the "calories in, calories out" approach, in which you strive to burn more calories than you consume. There's only one problem: calculating your calorie burn is more difficult than it appears.

The quantity of calories burned by a person while performing a specific activity or movement is determined by a variety of characteristics, including height and weight, gender, and muscle mass. However, your health and the weather might have an impact on how many calories you burn when exercising.

"You work harder running 6 miles (9.7 kilometers) in 80-degree (27 C) heat and high humidity than when it's 50 degrees (10 C) and dry," said Dr. Keith Anderson, a family, and sports medicine doctor with Novant Health in Charlotte, North Carolina. "Your body also works harder if you're fighting off a cold or if you didn't sleep well the night before. There's so much combined into metabolism."

Furthermore, calorie-tracking equipment like fitness watches are not always reliable. According to research published in the Journal of Personalized Medicine, while seven wrist-worn devices successfully detected heart rate in people walking, jogging, and cycling, none effectively estimated energy expenditure. The most accurate gadget was about 27% off, while the least accurate device was 93% off.

Exercise equipment isn't always reliable

Calorie counts on exercise machines like treadmills, stationary cycles, and elliptical machines are also unreliable. Ellipticals, for example, are notoriously inaccurate at calculating your calorie burn. According to a 2018 study published in the journal Exercise Medicine, these devices drastically overstate your calorie consumption. These devices claimed that when participants exercised at a moderate effort, they burned 200 more calories per hour than they really did in the research.

"You can't really rely on these exercise machines," said registered dietitian and nutritionist Kat Barefield, a nutrition master trainer with the National Academy of Sports Medicine. "Even if you get into an exercise physiology lab and get hooked up to sophisticated equipment, the results won't be totally accurate."

But how can people devise a sound fitness regimen if they don't know how many calories they burn during a certain workout? Anderson recommends doing full-body workouts since they burn the most calories.

"I'm training for the Ironman World Championships right now, and I absolutely burn more calories swimming and running than cycling," he said. Other solid options, Anderson said, are Pilates and high-intensity interval training, also known as HIIT workouts.

"The more movement you can involve, the better," Barefield said, noting you can use trekking poles when going out for a walk or hike to burn a few more calories. Even listening to music can help. "Music will give you more energy to move at more intense speeds," she said.

NEAT ways to get fit

Some individuals would rather concentrate on the "calories in" portion of the equation. No matter where you look, the calorie counts for various foods seem to be very comparable. Few will argue with the US Department of Agriculture's claim that one medium-sized apple provides around 100 calories, depending on the apple variety and size. Furthermore, the Food and Drug Administration requires that the number of calories in most prepared dishes and standard items in many chain restaurants be disclosed. Counting calories, on the other hand, might be difficult, according to Anderson.

"I don't know many patients who can accurately calculate their calorie intake," he said. "They may look up on the internet that a PBJ is X calories, but exactly how much peanut butter are they putting on their sandwich? Are they eating the crust? It all comes down to estimates."

Barefield's clients aren't usually asked to keep track of their calories. She instead advises them to vary their activities. The more you do a certain exercise, such as cycling, the more effective your body becomes at it. And as your body grows more efficient, it burns fewer calories. As a result, completing a few various types of exercise each week is beneficial.

She's also a believer in NEAT, or non-exercise activity thermogenesis, which is a fancy acronym for the calories you burn when you don't eat, sleep, or exercise.

"It's things like going up stairs, gardening, pacing while you talk on the phone -- that's all NEAT," Barefield said.

Just keep moving

Dr. James Levine noted in his 2009 book "Move a Little, Lose a Lot" that our sedentary lifestyle robs us of 1,500 to 2,000 NEAT calories each day. The first treadmill desk was invented by Levine, an endocrinologist, as a technique to promote NEAT.

Increasing your NEAT may be more beneficial than counting calories or attempting to determine which exercise burns the most calories. But, Anderson cautioned, don't get caught up in the technicalities while thinking about NEAT.

"You can spend a lot of time adding up calories, but that's stressful," he said. "And we all have way too much stress in life already." Instead, Anderson said to focus on your health, not weight, and on moving regularly, whether that's running, walking, or dancing in your home with the drapes closed.

"Fitness is more important than fatness," he said, "and exercise will outperform dieting every single time."