The Science Behind Fat Loss

Fat loss is often cited as a common goal for people starting a new fitness and nutrition routine. Unfortunately we are bombarded with toxic brands like “Slim Fast” or fad diets such as “Atkins” or “Keto” as the answer to our fat loss goals. These diets are not only overly restrictive, they are simply not sustainable. While it’s possible someone will meet their fat-loss goals by participating in one of these diets, more often than not, adhering to the diet becomes overly stressful and eventually it is completely abandoned. 

If fat loss is the goal, slow and steady wins the race. Setting realistic, measurable, and attainable goals is key to remaining motivated and staying the course. Ditching the fad diets and instead following scientific, evidence-based practices is crucial.  

Energy In, Energy Out
At a VERY high level view, fat loss is achieved through having a deficit in calories consumed versus calories expended. One pound of body fat is roughly 3,500 stored calories, meaning you will need to have a deficit of 500 calories per day to lose one pound of body fat in a week. While not 100% accurate, fitness trackers such as MyFitnessPal can help with monitoring calories consumed versus calories burned. The number of calories our body burns largely is dependent on our:

• Resting Metabolic Rate. Energy expenditure when we are at complete rest

• Exercise Activity Thermogenesis. The amount of calories burned during structured exercise, such as running, lifting weights, cycling, etc

• Thermic Effect of Food (TEF). The amount of calories burned processing, digesting, and absorbing food within our digestive system. Protein has a higher TEF, meaning your body burns more calories breaking down, digesting, and absorbing protein. Therefore, someone looking to burn more fat should target on a daily basis to consume at least 1 gram of protein per pound of bodyweight.

• Nonexercise Activity Thermogenesis. The amount of calories burned doing non-structured activities such as walking, chores around the house, or gardening. Even standing up and walking around the house/office between work meetings can make a huge difference in calories burned throughout the day.

Workout Intensity Levels
Have you ever used a piece of cardio equipment at the gym that had a graphic for the “fat burning zone”? While exercising at a lower intensity does utilize a larger percentage of fat as fuel, the calories expended is lower, unless the activity is performed for a long period of time.

For someone who only has 30-60 minutes available to workout, opting for moderate to high intensity exercises, such as circuit resistance training, will lead to more TOTAL calories burned, thus contributing to more efficient fat-loss efforts. You can also further boost your calories burned by decreasing rest times between circuits and/or coupling high-intensity cardio exercises, such as jumping jacks, burpees, squat jumps, etc within your resistance training program.